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{{Short description|Family of spiders}}
{{Use dmy dates|date=September 2010}}
{{About|the Theraphosidae family of spiders|the European tarantula wolf spider|Lycosa tarantula|other uses}}
{{About|the spider family, Theraphosidae|the European tarantula wolf spider|Lycosa tarantula|other uses}}
{{Distinguish|tarantella}}
{{Distinguish|tarantella}}
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{{automatic taxobox
{{Use dmy dates|date=August 2019}}
| name = Tarantula
{{more citations needed|date=February 2016}}
| taxon=Theraphosidae
{{Automatic taxobox
| image = Brachypelma smithi 2009 G03.jpg
| fossil_range = {{Fossil range|Cretaceous|present}}
| image_width = 240px
| image = Brachypelma vagans p1.jpg
| image_caption = [[Mexican redknee tarantula]] <br>''Brachypelma smithi''
| image_caption = ''[[Tliltocatl vagans]]''
| authority = [[Tamerlan Thorell|Thorell]], 1870
| diversity_link = List of Theraphosidae species
| taxon = Theraphosidae
| authority = [[Tamerlan Thorell|Thorell]], 1869
| diversity = 123 genera, 931 species
| range_map = Distribution.theraphosidae.1.png
| range_map = Distribution.theraphosidae.1.png
| subdivision_ranks =
| range_map_width = 250px
| subdivision =
| subdivision_ranks = Subfamilies
| diversity = [[#Genera|166 genera]], [[List of Theraphosidae species|1,100 species]]
| subdivision =
| diversity_ref = <ref name=NMBE />
[[Acanthopelminae]]<br />
[[Aviculariinae]]<br />
[[Eumenophorinae]]<br />
[[Harpactirinae]]<br />
[[Ischnocolinae]]<br />
[[Ornithoctoninae]]<br />
[[Poecilotheriinae]]<br />
[[Selenocosmiinae]]<br />
[[Selenogyrinae]]<br />
[[Spelopelminae]]<br />
[[Stromatopelminae]]<br />
[[Theraphosinae]]<br />
[[Thrigmopoeinae]]
</small>
}}
}}
'''Tarantulas''' comprise a group of often hairy and very large [[arachnid]]s belonging to the '''Theraphosidae''' [[Family (taxonomy)|family]] [[Spider taxonomy#Table of Families|of spiders]], of which approximately 900 species have been identified. This article only describes members of Theraphosidae, although some other members of the same suborder are commonly referred to as "tarantulas". Most species of tarantulas are not dangerous to humans, and some species have become popular in the exotic pet trade.


'''Tarantulas''' comprise a group of large and often hairy [[spider]]s of the [[Family (biology)|family]] '''Theraphosidae'''.<ref>{{cite book |last1=Shultz |first1=Stanley |last2=Shultz |first2=Marguerite |title=The Tarantula Keeper's Guide |date=2009 |publisher=Barron's |location=Hauppauge, New York |isbn=978-0-7641-3885-0 |page=28}}</ref> {{As of|2023|December}}, 1,100 [[species]] have been identified, with 166 [[genera]].<ref name=WSC_stats>{{citation |title=Currently valid spider genera and species |work=World Spider Catalog |publisher=Natural History Museum Bern |url=http://www.wsc.nmbe.ch/statistics/ |access-date=2022-08-20 }}</ref> The term "tarantula" is usually used to describe members of the family Theraphosidae, although many other members of the same infraorder ([[Mygalomorphae]]) are commonly referred to as "tarantulas" or "false tarantulas". Some of the more common species have become popular in the [[exotic pet]] trade. Many [[New World]] species kept as pets have [[seta]]e known as [[urticating hair]]s that can cause irritation to the skin, and in extreme cases, cause damage to the eyes.<ref name=Blaikie97/>
==Overview==
Like all [[arthropod]]s, the tarantula is an [[invertebrate]] that relies on an [[exoskeleton]] for muscular support. Like other [[Arachnid]]a a tarantula’s body comprises two main parts, the [[prosoma]] (or cephalothorax) and the [[opisthosoma]] (or abdomen). The prosoma and opisthosoma are connected by the [[Pedicel (spider)|pedicle]], or [[Spider anatomy|pregenital somite]]. This waist-like connecting piece is actually part of the prosoma and allows the opisthosoma to move in a wide range of motion relative to the prosoma.


== Overview ==
Tarantulas sizes range from as small as a fingernail to as large as a dinner plate when the legs are fully extended. Depending on the species, the body length of tarantulas ranges from {{convert|2.5|to|10|cm|0}}, with leg spans of {{convert|8|-|30|cm|0|adj=on}}. Leg span is determined by measuring from the tip of the back leg to the tip of the front leg on the opposite side. Some of the largest species of tarantula may weigh over {{convert|85|g|0}}; the largest of all, the [[goliath birdeater]] (''Theraphosa blondi'') from Venezuela and Brazil, has been reported to attain a weight of {{convert|150|g}} and a leg-span of up to {{convert|30|cm}}, males being the longer and females greater in girth.
Like all [[arthropod]]s, the tarantula is an [[invertebrate]] that relies on an [[exoskeleton]] for muscular support.<ref name="Pomeroy, R.">Pomeroy, R. (2014, February 4). Pub. Real Clear Science, "Spiders, and Their Amazing Hydraulic Legs and Genitalia". Retrieved October 13, 2019, from https://www.realclearscience.com/blog/2013/02/spiders-their-amazing-hydraulic-legs-and-genitals.html.</ref> Like other [[Arachnid]]a, a tarantula's body comprises two main parts, the [[prosoma]] (or cephalothorax) and the [[opisthosoma]] (or abdomen). The prosoma and opisthosoma are connected by the [[Pedicel (spider)|pedicel]], or [[Spider anatomy|pregenital somite]]. This waist-like connecting piece is actually part of the prosoma and gives the opisthosoma a wide range of motion relative to the prosoma.


Depending on the species, the body length of tarantulas ranges from about {{convert|5|to|11|cm|in|frac=2|abbr=on}}<ref name="Blondi">Jovan, Dennis, Kj, & Kenneth. (2019, May 1). Theraphosa blondi. Retrieved October 13, 2019, from https://www.theraphosidae.be/en/theraphosa-blondi/ {{Webarchive|url=https://web.archive.org/web/20210518012418/https://www.theraphosidae.be/en/theraphosa-blondi/ |date=18 May 2021 }}.</ref> with leg spans of {{convert|8|-|30|cm|in|frac=2|abbr=on}}.{{citation needed|date=October 2019}} Leg span is determined by measuring from the tip of the back leg to the tip of the front leg on the opposite side. Some of the largest species of tarantula may weigh over {{convert|85|g|oz|frac=4|abbr=on}}; the largest of all, the [[goliath birdeater]] (''Theraphosa blondi'') from [[Venezuela]] and [[Brazil]], has been reported to attain a weight of {{convert|170|g|oz|frac=2|abbr=on}}<ref name="Naskrecki, Piotr">{{cite web |last1=Lewis |first1=Tanya |title=Goliath Encounter: Puppy-Sized Spider Surprises Scientist in Rainforest |url=http://www.livescience.com/48340-goliath-birdeater-surprises-scientist.html |website=LiveScience.com |publisher=Live Science |date=17 October 2014 |access-date=29 November 2014 |url-status=live |archive-url=https://web.archive.org/web/20141204074434/http://www.livescience.com/48340-goliath-birdeater-surprises-scientist.html |archive-date=4 December 2014 }}</ref> and a leg-span up to {{convert|30|cm|in|0|abbr=on}}, males being longer and females greater in girth. The fang size of this tarantula reaches a maximum of {{convert|1+1/2|in|cm|0|order=flip|abbr=on}}.<ref name="Naskrecki, Piotr" />
''Theraphosa apophysis'' (the pinkfoot goliath) was described 187 years after the goliath birdeater; therefore its characteristics are not as well attested.''Theraphosa blondi'' is generally thought to be the heaviest tarantula, and ''T. apophysis'' to have the greatest leg span. Two other species, ''[[Lasiodora parahybana]]'' (the Brazilian salmon birdeater) and ''Lasiodora klugi'', rival the size of the two goliath spiders.


[[File:Tarantula Burrow.jpg|thumb|Opening to a tarantula burrow]]
Most species of North American tarantulas are brown. Elsewhere species have been found that variously display cobalt blue (''[[cobalt blue tarantula|Haplopelma lividum]]''), black with white stripes (''[[Aphonopelma seemanni]]''), yellow leg markings (''[[Eupalaestrus campestratus]]''), metallic blue legs with vibrant orange abdomen and greenbottle blue (''[[greenbottle blue tarantula|Chromatopelma cyaneopubescens]]''). Their natural habitats include [[savanna]], [[grassland]]s such as the [[pampa]]s, [[rainforest]]s, [[desert]]s, [[scrubland]], [[mountain]]s, and [[cloud forest]]s. They are generally classed among the terrestrial types. They are burrowers that live in the ground.
''[[Theraphosa apophysis]]'' (the pinkfoot goliath) was described 187 years after the goliath birdeater, so its characteristics are not as well attested. ''[[Goliath birdeater|T. blondi]]'' is generally thought to be the heaviest tarantula, and ''[[Theraphosa apophysis|T. apophysis]]'' has the greatest leg span. Two other species, ''[[Lasiodora parahybana]]'' (the Brazilian salmon birdeater) and ''[[Lasiodora klugi]]'', rival the size of the two goliath spiders.

[[File:Tarantula in burrow.png|thumb|Tarantula at the mouth of its burrow]]
Most species of [[North America]]n tarantulas are brown. Elsewhere, species have been found that variously display cobalt blue (''[[Cobalt blue tarantula|Cyriopagopus lividus]]''), black with white stripes (''[[Aphonopelma seemanni]]''), yellow leg markings (''[[Eupalaestrus campestratus]]''), metallic blue legs with vibrant orange abdomen and green prosoma (''[[Greenbottle blue tarantula|Chromatopelma cyaneopubescens]]''). Their natural habitats include [[savanna]], [[grassland]] such as in the [[pampa]]s, [[rainforest]], [[desert]], [[scrubland]], [[mountain]]s, and [[cloud forest]]. They are generally classed among the terrestrial types. They are burrowers that live in the ground.


Tarantulas are becoming increasingly popular as pets and some species are readily available in captivity.
Tarantulas are becoming increasingly popular as pets and some species are readily available in captivity.


== Identification ==
==Etymology==
Tarantulas can be confused with other members of the order [[Mygalomorphae]], such as [[List of trapdoor spiders|trapdoor spiders]], [[funnel-web spider]]s and [[purseweb spider]]s. They can also be confused with some members of the order [[Araneomorphae]] such as the [[Lycosidae]] family. There are multiple ways to identify a tarantula. First the hairs: in the [[Americas]] most tarantulas have [[urticating hair]]s, though some, such as the ''[[Hemirrhagus]]'' genus, lack these. The hairs are usually more noticeable than with most other [[spider]]s. Another is the size, as tarantulas tend to be bigger, but this is again not a failproof way. They also do not use their [[Spider web|webs]] for hunting, instead using them as building material or tripwire.<ref name=":0">{{Cite web |title=Tarantula vs Other Spiders – 7 Key Differences – Fauna Facts |url=https://faunafacts.com/spiders/tarantula-vs-spider-differences/ |access-date=2022-07-15 |language=en-US}}</ref>
The spider originally bearing the name "tarantula" was ''[[Lycosa tarantula]]'', a species of [[wolf spider]] native to Mediterranean Europe.<ref name= "JHFLS">Fabre, Jean-Henri; Translated by Alexander Teixeira de Mattos (1916) [http://archive.org/details/lifespider00fabrgoog The Life of the spider], Dodd, Mead, New York.</ref> The name derived from that of the southern [[Italy|Italian]] town of [[Taranto]]. The term ''"tarantula"'' subsequently was applied to almost any large, unfamiliar species of ground-dwelling [[spider]], in particular to the [[Mygalomorphae]] and especially to the new-world Theraphosidae. Compared to tarantulas, wolf spiders are not particularly large or hairy, so among English speakers in particular, the usage eventually shifted in favour of the Theraphosidae, even though they are barely related to the wolf spiders, being in a different [[infraorder]].


One of the most decisive ways to tell is by looking at their fangs. Tarantula fangs face downwards, as opposed to those of [[Araneomorphae|true spiders]], which face each other, allowing them to make pincerlike motions. They also own two [[book lung]]s, as opposed to true spiders which only have one. Their lifespan is also longer than most spiders.<ref name=":0" />
===New-world and other divergent usages===
<gallery widths="180" heights="180" perrow="2" caption="Comparison of the fangs of a tarantula and of a true spider>
[[File:Austin tarantula.jpg|thumbnail|right|A tarantula next to a US size 11 shoe, to show scale]]
File:Lasiodora parahybana, chelicerae.JPG|alt=|Fangs of ''[[Lasiodora parahybana]]'', a tarantula, from below
When theraphosids were encountered in the [[Americas]], they were named "tarantulas", causing usage of the term to shift to the tropical spiders. Nevertheless, these spiders belong to the suborder [[Mygalomorphae]], and are not closely related to wolf spiders.
File:Kaldari Phidippus johnsoni male defense.jpg|alt=|Fangs of ''[[Phidippus johnsoni]]'', a member of the [[jumping spider]] family Salticidae, from the front
</gallery>
[[File:Austin tarantula.jpg|thumbnail|A tarantula next to a U.S. size 11 shoe, to show scale, taken near Austin, Texas]]


== Etymology ==
The name "tarantula" is also mistakenly applied to other large-bodied spiders, including the purseweb spiders or [[atypical tarantula]]s, the funnel-webs ([[Dipluridae]] and [[Hexathelidae]]), and the "[[dwarf tarantula]]s". These spiders are related to tarantulas (all being mygalomorphs), but are classified in different [[family (biology)|families]]. [[Huntsman spider]]s of the family Sparassidae have also been termed "tarantulas" because of their large size. In fact, they are not related, belonging to the suborder [[Araneomorphae]].
The spider originally bearing the name ''tarantula'' was ''[[Lycosa tarantula]]'', a species of [[wolf spider]] native to Mediterranean Europe.<ref name="JHFLS">Fabre, Jean-Henri; Translated by Alexander Teixeira de Mattos (1916) [https://archive.org/details/lifespider00fabrgoog The Life of the spider], Dodd, Mead, New York.</ref> The name is derived from the southern [[Italy|Italian]] town of [[Taranto]].<ref>{{cite web|title=Taranto|url=http://www.lifeinitaly.com/tourism/puglia/taranto|website=lifeinitaly|access-date=29 August 2015|url-status=live|archive-url=https://web.archive.org/web/20150904145001/http://www.lifeinitaly.com/tourism/puglia/taranto|archive-date=4 September 2015}}</ref> The term ''tarantula'' was subsequently applied to almost any large, unfamiliar species of ground-dwelling spider, in particular to the [[Mygalomorphae]] and especially the [[New World]] [[Theraphosinae|Theraphosidae]]. Compared to tarantulas, [[wolf spider]]s are not particularly large or hairy, and so among English speakers in particular, usage eventually shifted in favour of the Theraphosidae, even though they are not closely related to wolf spiders at all, being in a different [[infraorder]].[[File:Mojave Tarantula.jpg|alt=Tarantula native to the Mojave Desert searches for burrow.|thumb|''[[Aphonopelma mojave]]'', a tarantula native to the Mojave Desert, searches for a burrow.]]
The name ''tarantula'' is also incorrectly applied to other large-bodied spiders, including the [[purseweb spider]]s or [[atypical tarantula]]s, the funnel-webs ([[Dipluridae]] and [[Hexathelidae]]), and the [[dwarf tarantula]]s. These spiders are related to tarantulas (all being [[Mygalomorphae|mygalomorphs]]) but fall into different [[Family (biology)|families]] from them. [[Huntsman spider]]s of the family [[Sparassidae]] have also been termed ''tarantulas'' because of their large size, when, in fact, they are not related. Instead, huntsman spiders belong to the infraorder [[Araneomorphae]].


===The element ''pelma'' in genus names===
==Distribution==
<!--There are wikilinks here so fix or leave an anchor if you change the section title-->
Tarantulas of various species occur in the southern and western parts of the United States, in Central America, and throughout South America. Other species occur variously throughout Africa, much of Asia and all of Australia. In Europe, some species occur in Spain, Portugal, Turkey, Italy, and Cyprus.
Many theraphosid genera have names, either accepted or [[Synonym (taxonomy)|synonymous]], containing the element ''pelma''. This can be traced back to [[Carl Ludwig Koch]] in 1850,<ref name=EstrCame12/> who in describing his new genus ''Eurypelma'' wrote, "{{lang|de|Die Sammetbürste der Fussohlen sehr breit}}" ({{lit|the velvet-brush of the footsole very wide}}).<ref name=Koch50/> German [[Arachnology|arachnologists]] use the word {{lang|de|Fuß}} to refer to the [[Glossary of spider terms#tarsus|tarsus]] (the last article of a spider's leg).<ref name=Foel92/> Translations of {{lang|de|Sammetbürste}} into Latin use the word {{lang|la|scopula}}.<ref name=Schm94/> Hence in English arachnological terminology, Koch meant 'the [[Glossary of spider terms#scopula|scopula]] of the base of the tarsus very wide'. ''Eury-'' is derived from the [[Ancient Greek|Greek]] {{transliteration|grc|eurýs}} ({{wikt-lang|grc|εὐρύϛ}}), meaning 'wide', while {{transliteration|grc|pélma}} ({{wikt-lang|grc|πέλμα}}) means 'the sole of the foot',<ref name=EstrCame12/> paralleling Koch's use of {{lang|de|Fußsohle}} (in modern spelling). Thus ''Eurypelma'' literally means 'wide footsole'; however, arachnologists have conventionally taken ''pelma'' in such names to refer to the scopula, so producing the meaning 'with a wide scopula'.<ref name=EstrCame12/>


Other genus names or synonyms that Estrada-Alvarez and Cameron regard as having 'footsole' or 'scopula' meanings include:<ref name=EstrCame12/>
==Habits==
*''[[Acanthopelma]]'' – Greek {{transliteration|grc|ácantha}} ({{wikt-lang|grc|ἄκανθα}}) 'thorn, spine'; overall meaning 'spiny footsole'
Some [[genus|genera]] of tarantulas hunt prey primarily in trees; others hunt on or near the ground. All tarantulas can produce [[Spider silk|silk]] &ndash; while arboreal species will typically reside in a silken "tube tent", terrestrial species will line their burrows with silk to stabilize the burrow wall and facilitate climbing up and down. Tarantulas mainly eat insects and other arthropods, using ambush as their primary method of prey capture. The biggest tarantulas can kill animals as large as [[lizard]]s, [[mouse|mice]], [[bird]]s and small [[snake]]s.
*''[[Brachypelma]]'' – Greek {{transliteration|grc|brachýs}} ({{wikt-lang|grc|βραχύϛ}}) 'short'; overall meaning 'short scopula'
*''[[Metriopelma]]'' – Greek {{transliteration|grc|métrios}} ({{wikt-lang|grc|μέτριοϛ}}) 'of moderate size'; overall meaning 'medium length scopula'
*''[[Schizopelma]]'' – from the Greek origin combining form ''schizo-'' ({{wikt-lang|grc|σχίζω}}) 'split'; overall meaning 'split footsole'
*''[[Sericopelma]]'' – Greek {{transliteration|grc|sericós}} ({{wikt-lang|grc|σηρικόϛ}}) 'silky'; overall meaning 'silken scopula'


Later, particularly following genus names published by [[Reginald Innes Pocock|R.I. Pocock]] in 1901,<ref name=Poco01/> the element ''pelma'' appears to have become synonymous with 'theraphosid'. For example, the author of ''Cardiopelma'' writes, "{{lang|fr|Cardiopelma fait réference aux genitalia de la femelle qui évoquent la forme d'un Coeur}}" ('Cardiopelma refers to the female genitalia that evoke the shape of a heart'), with no reference to either 'footsole' or 'scopula'. Names interpreted in this way include:<ref name=EstrCame12/>
==Appendages==
*''[[Aphonopelma]]'' – Greek {{transliteration|grc|áphonos}} ({{wikt-lang|grc|ἄφωνοϛ}}) 'soundless'; overall meaning 'theraphosid without sound'
[[Image:Poecilotheria Regalis.jpg|thumb|right|Sub-adult Female ''[[Poecilotheria regalis]]'']]
*''[[Cardiopelma]]'' – Greek {{transliteration|grc|cardía}} ({{wikt-lang|grc|καρδία}}) 'heart'; overall meaning 'heart theraphosid' (referring to the heart-shaped female genitalia)
*''[[Clavopelma]]'' – Latin {{wikt-lang|la|clavis}} 'club'; overall meaning 'theraphosid with club-shaped hairs'
*''[[Delopelma]]'' – Greek {{transliteration|grc|delós}} ({{wikt-lang|grc|δηλόϛ}}) 'clear, obvious, visible, conspicuous, plain'; overall meaning 'theraphosid without plumose hair'
*''[[Gosipelma]]'' – the element ''gosi-'' means 'desert', relating to the [[Goshute|Gosiute people]]; overall meaning 'desert theraphosid'
*''[[Spelopelma]]'' – Greek {{transliteration|grc|spélaion}} ({{wikt-lang|grc|σπήλαιον}}) 'cave'; overall meaning 'cave theraphosid'


== Distribution ==
The eight legs, the two [[chelicerae]] with their fangs, and the [[pedipalp]]s are attached to the prosoma. The chelicerae are two double segment appendages that are located just below the eyes and directly forward of the mouth. The chelicerae contain the venom glands that vent through the fangs. The fangs are hollow extensions of the chelicerae that inject venom into prey or animals that the tarantula bites in defense, and they are also used to masticate. These fangs are articulated so that they can extend downward and outward in preparation to bite or can fold back toward the chelicerae as a pocket knife blade folds back into its handle. The chelicerae of a tarantula completely contain the venom glands and the muscles that surround them, and can cause the venom to be forcefully injected into prey.
Tarantulas of various species occur throughout the [[United States]], [[Mexico]], in [[Central America]], and throughout [[South America]]. Other species occur variously throughout [[Africa]], much of [[Asia]] (including the [[Ryukyu Islands]] in southern [[Japan]]), and all of [[Australia]]. In [[Europe]], some species occur in [[Spain]], [[Portugal]], [[Turkey]], southern [[Italy]], and [[Cyprus]].


== Habits ==
The pedipalpi are two six-segment appendages connected to the [[thorax]] near the mouth and protruding on either side of both chelicerae. In most species of tarantula, the pedipalpi contain sharp jagged plates used to cut and crush food often called the [[arthropod leg|coxae]] or [[Arthropod mouthparts#Maxilla|maxillae]]. As with other spiders, the terminal portion of the pedipalpi of males function as part of its reproductive system. Male spiders spin a silken platform (sperm web) on the ground onto which they release semen from glands in their opistoma. Then they insert their pedipalps into the semen, absorb the semen into the pedipalps, and later insert the pedipalps (one at a time) into the reproductive organ of the female, which is located in her abdomen. The terminal segments of the pedipalps of male tarantulas are moderately larger in circumference than those of a female tarantula. Male tarantulas have special [[Spinneret (spider)|spinneret]]s surrounding the genital opening. Silk for the sperm web of the tarantula is exuded from these special spinnerets.
Some [[Genus|genera]] of tarantulas hunt prey primarily in trees; others hunt on or near the ground. All tarantulas can produce [[Spider silk|silk]]; while arboreal species typically reside in a silken "tube tent", [[Terrestrial animal|terrestrial]] species line their [[burrow]]s with silk to stabilize the [[burrow]] wall and facilitate climbing up and down. Tarantulas mainly eat large insects and other arthropods such as [[centipede]]s, [[millipede]]s, and other [[spider]]s, using ambush as their primary method of prey capture. Armed with their massive, powerful [[chelicerae]] tipped with long, [[chitinous]] fangs, tarantulas are well-adapted to killing other large [[arthropod]]s. The biggest tarantulas sometimes kill and consume small vertebrates such as [[lizard]]s, [[Mouse|mice]], [[bat]]s, [[bird]]s, and small [[snake]]s.


=== Appendages ===
[[File:Lasiodora parahybana, claws.JPG|left|thumb|Claws at the end of the leg of ''[[Lasiodora parahybana]]'']]
[[File:Tarantula, Attacking Position, Photo by Sascha Grabow.jpg|thumb|right|Brazilian tarantula in defensively threatening position]]
[[File:Poecilotheria Regalis.jpg|thumb|right|Subadult female ''[[Poecilotheria regalis]]'']]


The eight legs, the two chelicerae with their fangs, and the [[pedipalp]]s are attached to the [[prosoma]]. The [[chelicerae]] are two double-segmented appendages located just below the eyes and directly forward of the mouth. The chelicerae contain the [[venom]] glands that vent through the fangs. The fangs are hollow extensions of the chelicerae that inject venom into prey or animals that the tarantula bites in defense, and they are also used to [[masticate]]. These fangs are articulated so that they can extend downward and outward in preparation to bite or can fold back toward the [[chelicerae]] as a pocket knife blade folds back into its handle. The chelicerae of a tarantula completely contain the venom glands and the muscles that surround them, and can cause the venom to be forcefully injected into prey.
A tarantula has four pairs of legs and two additional pairs of appendages. Each leg has seven segments which, from the [[prosoma]] out, are: coxa, trochanter, femur, patella, tibia, tarsus and pretarsus, and claw. Two or three retractable claws are at the end of each leg. These claws are used to grip surfaces for climbing. Also on the end of each leg, surrounding the claws, is a group of hairs. These hairs, called the scopula, help the tarantula to grip better when climbing surfaces like glass. The fifth pair are the pedipalps which aid in feeling, gripping prey, and mating in the case of a mature male. The sixth pair of appendages are the chelicerae and their attached fangs. When walking, a tarantula's first and third leg on one side move at the same time as the second and fourth legs on the other side of his body. The muscles in a tarantula's legs cause the legs to bend at the joints, but to extend a leg, the tarantula increases the pressure of blood entering the leg.


The pedipalpi are two six-segmented appendages connected to the prosoma near the mouth and protruding on either side of both chelicerae. In most species of tarantulas, the pedipalpi contain sharp, jagged plates used to cut and crush food often called the [[Arthropod leg|coxae]] or [[Arthropod mouthparts#Maxilla|maxillae]]. As with other spiders, the terminal portions of the pedipalpi of males function as part of their reproductive system. Male spiders spin a silken platform (sperm web) on the ground onto which they release [[semen]] from glands in their [[opisthosoma]]. Then they insert their pedipalps into the semen, absorb the semen into the pedipalps, and later insert the pedipalps (one at a time) into the reproductive organ of the female, which is located in her abdomen. The terminal segments of the pedipalps of male tarantulas are moderately larger in circumference than those of a female tarantula. Male tarantulas have special [[Spinneret (spider)|spinnerets]] surrounding the genital opening. Silk for the sperm web of the tarantula is exuded from these special spinnerets.
Tarantulas, like almost all other spiders, have their primary spinnerets at the end of the opisthosoma. Unlike most spider species in the suborder [[Araneomorphae]], which includes the majority of extant spider species, and most of which have six, tarantula species have two or four spinnerets. Spinnerets are flexible tubelike structures from which the spider exudes its silk. The tip of each spinneret is called the spinning field. Each spinning field is covered by as many as one hundred spinning tubes through which silk is exuded. This silk hardens on contact with the air to become a threadlike substance.


[[File:Lasiodora parahybana, claws.JPG|thumb|Claws at the end of the leg of ''[[Lasiodora parahybana]]'']]
===Silk-producing feet===
[[File:Tarantula, Attacking Position, Photo by Sascha Grabow.jpg|thumb|right|A Brazilian tarantula in defensively threatening position]]
In 2006 in the ''Journal of Experimental Biology'' a paper described observations suggesting that some tarantulas have silk-producing [[Spider silk#Biosynthesis|spigot]]s on their feet. The authors assert that these structures enabled the spiders to cling to smooth surfaces and thus avoid harmful falls.
<ref>{{cite pmid|17006505}}</ref> In 2011, Dr. Claire Rind and her colleagues from [[Newcastle University]] conducted experiments inferring the likelihood that all tarantulas are able to produce silk from their [[Arthropod leg#Chelicerata|tarsi]] (feet).<ref>{{cite doi| 10.1242/jeb.055657
}}</ref>
Describing her experiments in a BBC Nature report (16 May 2011), Dr. Rind includes an electron microscope image purportedly revealing microscopic silk producing structures on the spiders' feet, and noting that the three species involved in the research were very distantly related, concludes: "So it's likely that all tarantulas produce silk threads from their feet."<ref>{{cite news
| title = Tarantulas eject silk from feet
| author = Victoria Gill
| url = http://www.bbc.co.uk/nature/13382903
| agency = BBC
| date = 16 May 2011
| accessdate = 2011-05-16
| quote = An electron microscope revealed microscopic silk producing structures on the spiders' feet.
}}</ref>


A tarantula has four pairs of legs and two additional pairs of appendages. Each leg has seven segments, which from the prosoma out are: coxa, trochanter, femur, patella, tibia, tarsus and pretarsus, and claw. Two or three retractable claws at the end of each leg are used to grip surfaces for climbing. Also on the end of each leg, surrounding the claws, is a group of bristles, called the scopula, which help the tarantula to grip better when climbing surfaces such as glass. The fifth pair is the pedipalps, which aid in feeling, gripping prey, and mating in the case of a mature male. The sixth pair of appendages is the chelicerae and their attached fangs. When walking, a tarantula's first and third legs on one side move at the same time as the second and fourth legs on the other side of its body. The muscles in a tarantula's legs cause the legs to bend at the joints, but to extend a leg, the tarantula increases the pressure of [[Hemolymph|haemolymph]] entering the leg.
Silk production from organs other than the spinnerets has been documented in other spiders such as from the [[chelicerae]] of [[Scytodidae]] family spiders, making the extraordinary claim plausible. However, the existence of silk-producing organs on the feet of tarantulas is currently considered controversial. Although the 2006 discovery is supported by Dr. Rind's 2011 study,<ref>{{cite doi|10.1242/jeb.055657}} <!--doi: 10.1242/jeb.055657 June 1, 2011 J Exp Biol 214, 1874-1879.--></ref> two 2012 studies refute the claim, one of them proposing that the structures described as spigots are actually [[chemoreceptor]]s.<ref>{{cite doi|10.1242/jeb.066811}}</ref><ref>{{cite doi|10.1242/jeb.069690}}</ref>


Tarantulas, like almost all other spiders, have their primary spinnerets at the end of the opisthosoma. Unlike most spider species in the infraorder [[Araneomorphae]], which includes the majority of extant spider species, and most of which have six, tarantula species have two or four spinnerets. Spinnerets are flexible, tube-like structures from which the [[spider]] exudes its silk. The tip of each spinneret is called the spinning field. Each spinning field is covered by as many as 100 spinning tubes through which silk is exuded. As the silk is pulled out of the spinnerets, the shear forces cause proteins in the silk to crystallize, transforming it from a liquid to a solid thread.
==Digestive system==

== Digestive system ==
[[File:Tarantula, food leftovers.JPG|right|thumb|Tarantula food leftovers]]
[[File:Tarantula, food leftovers.JPG|right|thumb|Tarantula food leftovers]]
[[File:Lasiodora parahybana, eyes.JPG|right|thumb|Eye ports seen in an [[exuvia]] (moulted skin).]]
[[File:Lasiodora parahybana, eyes.JPG|right|thumb|Eye ports seen in an [[exuvia]] (molted skin)]]
The tarantula's mouth is located under its chelicerae on the lower front part of its prosoma. The mouth is a short straw-shaped opening that can only suck, meaning that anything taken into it must be in liquid form. Prey with large amounts of solid parts, such as mice, must be crushed and ground up or predigested, which is accomplished by coating the prey with digestive juices that are secreted from openings in the chelicerae.
The tarantula's mouth is located under its [[chelicerae]] on the lower front part of its [[Cephalothorax|prosoma]]. The mouth is a short, straw-shaped opening that can only suck, meaning that anything taken into it must be in liquid form. Prey with large amounts of solid parts, such as mice, must be crushed and ground up or predigested, which is accomplished by coating the prey with digestive juices secreted from openings in the [[chelicerae]].


The tarantula's digestive organ (stomach) is a tube that runs the length of its body. In the prosoma, this tube is wider and forms the sucking stomach. When the sucking stomach's powerful muscles contract, the stomach is increased in cross-section, creating a strong sucking action that permits the tarantula to suck its liquefied prey up through the mouth and into the intestines. Once the liquefied food enters the intestines, it is broken down into particles small enough to pass through the intestine walls into the [[hemolymph]] (blood stream) where it is distributed throughout the body. After feeding, the leftovers are formed into a small ball by the tarantula and thrown away. In a terrarium, they often put them into the same corner.<ref>Kovařík, F (2001), ''Chov sklípkanů'' (Keeping Tarantulas); Madagaskar, [[Jihlava]], p. 23</ref> As these balls are not perfect hosts for [[mold]]s and [[parasite]]s, they must be removed regularly.
The tarantula's digestive organ (stomach) is a tube that runs the length of its body. In the [[prosoma]], this tube is wider and forms the sucking stomach. When the sucking stomach's powerful muscles contract, the stomach is increased in cross-section, creating a strong sucking action that permits the tarantula to suck its liquefied prey up through the mouth and into the intestines. Once the liquefied food enters the intestines, it is broken down into particles small enough to pass through the intestine walls into the [[hemolymph]] (blood stream), where it is distributed throughout the body. After feeding, the leftovers are formed into a small ball by the tarantula and thrown away. In a terrarium, they often put them into the same corner.<ref>Kovařík, F (2001), ''Chov sklípkanů'' (Keeping Tarantulas); Madagaskar, [[Jihlava]], p. 23</ref> <!-- As these balls are perfect hosts for [[mold]]s and [[parasite]]s, they must be removed regularly.


-->
==Nervous system==
A tarantula's central nervous system (brain) is located in the bottom of the inner [[Cephalothorax|prosoma]]. A tarantula perceives its surroundings primarily via sensory organs called [[seta]]e (hairs or spines). Although a tarantula has eyes, touch is its keenest sense, and in hunting it primarily depends on vibrations given off by the movements of its prey. A tarantula's setae are very sensitive organs and are used to sense chemical signatures, vibrations, wind direction, and possibly even sound. Tarantulas are also very responsive to the presence of certain chemicals such as [[pheromone]]s.


== Nervous system ==
[[Image:Brachypelma.albopilosum.eye.region.jpg|thumb|left|Closeup of a tarantula's eye]]
A tarantula's central nervous system (brain) is located in the bottom of the inner [[Cephalothorax|prosoma]]. A tarantula perceives its surroundings primarily via sensory organs called [[seta]]e (bristles or spines, sometimes referred to as hairs). Although a tarantula has eight eyes like most [[spider]]s, touch is its keenest sense, and in hunting, it primarily depends on vibrations given off by the movements of its prey. A tarantula's setae are very sensitive organs and are used to sense chemical signatures, vibrations, wind direction, and possibly even sound. Tarantulas are also very responsive to the presence of certain chemicals such as [[pheromone]]s.

[[File:Cyclosternum fasciatum, eye region.jpg|thumb|Close-up of a tarantula's eyes]]


The eyes are located above the chelicerae on the forward part of the prosoma. They are small and usually set in two rows of four. Most tarantulas are not able to see much more than light, darkness, and motion. Arboreal tarantulas generally have better vision compared with terrestrial tarantulas.
The eyes are located above the chelicerae on the forward part of the prosoma. They are small and usually set in two rows of four. Most tarantulas are not able to see much more than light, darkness, and motion. Arboreal tarantulas generally have better vision compared with terrestrial tarantulas.


==Respiratory system==
== Respiratory system ==
In all types of tarantula there are two sets of [[book lung]]s (breathing organs). The first pair of book lungs is located in a cavity inside the lower front part of the abdomen near where the abdomen connects to the cephalothorax and the second pair slightly farther back on the abdomen. Air enters the cavity through a tiny slit on each side of and near the front of the abdomen. Each lung consists of 15 or more thin sheets of folded tissue arranged like the pages of a book. These sheets of tissue are supplied by blood vessels. As air enters each lung, oxygen is taken into the blood stream through the blood vessels in the lungs. Needed moisture may also be absorbed from humid air by these organs.
All types of tarantulas have two sets of [[book lung]]s (breathing organs); the first pair is located in a cavity inside the lower front part of the abdomen near where the abdomen connects to the [[cephalothorax]], and the second pair is slightly farther back on the abdomen. Air enters the cavity through a tiny slit on each side of and near the front of the abdomen. Each lung consists of 15 or more thin sheets of folded tissue arranged like the pages of a book. These sheets of tissue are supplied by blood vessels. As air enters each lung, oxygen is taken into the blood stream through the blood vessels in the lungs. Needed moisture may also be absorbed from humid air by these organs.


==Circulatory system==
== Circulatory system ==
[[Image:wiki tarantula.jpg|thumb|right|Thermal image of an ectothermic tarantula on an endothermic human hand]]
[[File:wiki tarantula.jpg|thumb|right|Thermal image of an ectothermic tarantula on an endothermic human hand]]


A tarantula’s blood is unique; an oxygen-transporting protein is present (the copper-based [[hemocyanin]]) but not enclosed in blood cells such as the erythrocytes of mammals. A tarantula’s blood is not true blood but rather a liquid called [[haemolymph]], or hemolymph. There are at least four types of hemocytes, or hemolymph cells. The tarantula’s heart is a long slender tube that is located along the top of the opisthosoma. The heart is neurogenic as opposed to myogenic, so nerve cells instead of muscle cells initiate and coordinate the heart. The heart pumps hemolymph to all parts of the body through open passages often referred to as sinuses, and not through a circular system of blood vessels. If the exoskeleton is breached, loss of hemolymph will kill the tarantula unless the wound is small enough that the hemolymph can dry and close the wound.
A tarantula's blood is unique (not only in appearance); an oxygen-transporting protein is present (the copper-based [[hemocyanin]]), but not enclosed in blood cells such as the erythrocytes of mammals. A tarantula's blood is not true blood, but rather a liquid called [[hemolymph]] (or haemolymph). At least four types of [[hemocytes]], or hemolymph cells, are known.


The tarantula's heart is a long, slender tube located along the top of the [[opisthosoma]]. The heart is neurogenic as opposed to myogenic, so nerve cells instead of muscle cells initiate and coordinate the heart. It pumps hemolymph to all parts of the body through open passages often referred to as sinuses, and not through a circular system of blood vessels. If the [[exoskeleton]] is breached, loss of hemolymph will kill the spider unless the wound is small enough that the hemolymph can dry and close it.
==Predators==
Regardless of their fearsome reputation, tarantulas are themselves an object of predation. The most specialized of these predators are large members of the wasp family [[Pompilidae]]. In the Americas, these insects are termed "tarantula hawks", being [[parasitoid]]s of tarantulas. The largest tarantula hawks, such as those in the genus ''[[Pepsis]]'', will track, attack and kill large tarantulas. They use [[olfaction]] to find the lair of a tarantula. The wasp must deliver a sting to the underside of the spider's cephalothorax, exploiting the thin membrane between the basal leg segments. This paralyzes the spider and the wasp then drags it back into its burrow before depositing an egg on the prey's abdomen. The wasp then seals the spider in its burrow and flies off to search for more hosts. The wasp larva hatches and feeds on the spider's non-essential parts and, as it approaches pupation, it consumes the remainder.<ref>Piper, R (2007) ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', [[Greenwood Publishing Group|Greenwood Press]], ISBN 0313339228.</ref>


== Predators ==
Humans can also be considered predators of tarantulas. In addition to more mundane cuisine, tarantulas are considered a delicacy in certain cultures (e.g. Venezuela<ref>{{Cite web|last=Murton|first=Willow|title=Tarantula kebab anyone?|url=http://www.bbc.co.uk/blogs/food/2011/02/tarantula-kebab-anyone.shtml|work=BBC Food Blog'', with video from ''[[Human Planet]]|publisher=BBC|accessdate=7 December 2011}}</ref> and Cambodia). They are usually roasted over an open fire to remove the hairs (described further below) and then eaten.
Despite their large size and fearsome appearance and reputation, tarantulas themselves are prey for many other animals. The most specialized of these predators are large members of the wasp family [[Pompilidae]] such as the wasp ''[[Hemipepsis ustulata]]''. These wasps are called "[[tarantula hawk]]s". The largest tarantula hawks, such as those in the genus ''[[Pepsis]]'', track, attack, and kill large tarantulas. They use [[olfaction]] to find the lair of a tarantula. The wasp must deliver a sting to the underside of the spider's cephalothorax, exploiting the thin membrane between the basal leg segments. This paralyzes the spider, and the wasp then drags it back into its burrow before depositing an egg on the prey's abdomen. The wasp then seals the spider in its burrow and flies off to search for more hosts. The wasp egg hatches into a larva and feeds on the spider's inessential parts, and as it approaches pupation, it consumes the remainder.<ref>Piper, R (2007) ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', [[Greenwood Publishing Group|Greenwood Press]], {{ISBN|0313339228}}.</ref> Other arthropods, such as large scorpions and [[Scolopendra gigantea|giant centipedes]], are also known to prey on tarantulas.<ref>{{cite web|title=Wild or Giant Centipedes versus Other Predators|url=http://howtogetridofhousecentipedes.blogspot.com/2015/01/giant-centipedes-versus-predators.html|website=howtogetridofhousecentipedes|access-date=29 August 2015|url-status=live|archive-url=https://web.archive.org/web/20160304224952/http://howtogetridofhousecentipedes.blogspot.com/2015/01/giant-centipedes-versus-predators.html|archive-date=4 March 2016}}</ref>


Tarantulas are also preyed upon by a wide variety of vertebrates. Many of these, including lizards, frogs, birds, snakes and mammals, are generalist predators of all kinds of large arthropods. Mammals that have been known to prey on tarantulas, such as the [[coati]], [[kinkajou]], and [[opossum]] in the [[New World]], and [[mongoose]]s and the [[honey badger]] in the [[Old World]], are often immune to the venom of their arthropod prey.
Some other arthropods, such as [[Scolopendra gigantea|giant centipede]]s are also known to prey on tarantulas.{{Citation needed|date=June 2012}}
[[File:Brachypelma smithi, urticating hairs.JPG|right|thumb|Adult female ''[[Brachypelma smithi]]'', showing a bald patch after kicking hairs off of her abdomen.]]
Tarantulas have evolved specialized hairs to defend themselves against predators. Besides the normal "hairs" covering the body, some tarantulas also have a dense covering of irritating hairs called [[urticating hair]]s, on the opisthosoma, that they sometimes use as protection against enemies.<ref name=Cooke1972>{{cite journal|author=Cooke, J.A.L., Roth, V.D., Miller, F.H.|year=1972|title= The urticating hairs of theraphosid spiders|journal=American Museum novitates|pages= 2498|id={{hdl|2246/2705}}}}</ref> These hairs are present on [[New World]] species but not on specimens from the [[Old World]].


Humans also consume tarantulas for food in their native ranges. They are considered a delicacy in certain cultures (e.g. Venezuela<ref>{{Cite web|last=Murton|first=Willow|title=Tarantula kebab anyone?|url=https://www.bbc.co.uk/blogs/food/2011/02/tarantula-kebab-anyone.shtml|work=BBC Food Blog, with video from [[Human Planet]]|publisher=BBC|access-date=7 December 2011|url-status=live|archive-url=https://web.archive.org/web/20111206053619/http://www.bbc.co.uk/blogs/food/2011/02/tarantula-kebab-anyone.shtml|archive-date=6 December 2011}}</ref> and Cambodia). They can be roasted over an open fire to remove the bristles (described further below) and then eaten.
Urticating hairs are usually kicked off the abdomen by the tarantula, but it is noteworthy that some may simply rub the abdomen against the target, like the [[Avicularia]] genera. These fine hairs are barbed and serve to irritate. They can be lethal to small animals such as rodents. Some people are extremely sensitive to these hairs, and develop serious itching and rashes at the site. Exposure of the eyes and respiratory system to urticating hairs should be strictly avoided. Species with urticating hairs can kick these hairs off: they are flicked into the air at a target using their back pairs of legs. Tarantulas also use these hairs for other purposes such as to mark territory or to line their shelters (the latter such practice may discourage [[fly|flies]] from feeding on the spiderlings). Urticating hairs do not grow back, but are replaced with each [[moult]]. The intensity, amount, and flotation of the hairs depends on the species of tarantula. Many{{Who|date=October 2009}} owners of Goliath Birdeaters (''T. blondi'') claim that theraphosids have the worst urticating hairs.{{Citation needed|date=October 2009}}
[[File:Fried Tarantula in Cambodian Restaurant.jpg|right|thumb|Fried tarantula in a Cambodian restaurant]]


Tarantulas have evolved specialized bristles, or [[setae]], to defend themselves against predators. Besides the normal bristles covering the body, some tarantulas also have a dense covering of irritating bristles called [[urticating hair]]s, on the [[opisthosoma]], that they sometimes use as protection against enemies.<ref name=Cooke1972>{{cite journal|last1=Cooke|first1=J.A.L.|last2=Roth|first2=V.D.|last3=Miller|first3=F.H.|year=1972|title= The urticating hairs of theraphosid spiders|journal=American Museum Novitates|pages= 2498|hdl=2246/2705}}</ref> These bristles are present on most New World species, but not on any specimens from the Old World. Urticating hairs are usually kicked off the abdomen by the tarantula, but some may simply rub the abdomen against the target, like the genus ''[[Avicularia]]''. These fine bristles are barbed and serve to irritate. They can be lethal to small animals such as rodents. Some people are sensitive to these bristles, and develop serious itching and rashes at the site. Exposure of the eyes and respiratory system to urticating hairs should be strictly avoided. Species with urticating hairs can kick these bristles off; they are flicked into the air at a target using their back pairs of legs. Tarantulas also use these bristles for other purposes, such as to mark territory or to line their shelters (the latter such practice may discourage [[Fly|flies]] from feeding on the spiderlings). Urticating hairs do not grow back, but are replaced with each [[molt]]. The intensity, number, and flotation of the bristles depends on the species of tarantula.
To predators and other kinds of enemies, these hairs can range from being lethal to simply being a deterrent. With humans, they can cause irritation to eyes, nose, and skin, and more dangerously, the lungs and airways, if inhaled. The symptoms range from species to species, from person to person, from a burning itch to a minor rash. In some cases, tarantula hairs have caused permanent damage to human eyes.<ref>{{cite journal | last=Blaikie | first=Andrew J | coauthors = John Ellis, Roshini Sanders, Caroline J. MacEwen | date=24 May 1997 | title = Eye disease associated with handling pet tarantulas: three case reports | journal=[[BMJ]] | volume=314 | pmid = 9183200 | issue=7093 | pmc=2126783 | pages=1524–5 | doi=10.1136/bmj.314.7093.1524 }}</ref>


To predators and other enemies, these bristles can range from being lethal to simply being a deterrent. With humans, they can cause irritation to eyes, nose, and skin, and more dangerously, the lungs and airways, if inhaled. The symptoms range from species to species, from person to person, from a burning itch to a minor rash. In some cases, tarantula bristles have caused permanent damage to human eyes.<ref name=Blaikie97>{{cite journal | last=Blaikie | first=Andrew J |author2=John Ellis |author3=Roshini Sanders |author4=Caroline J. MacEwen | date=24 May 1997 | title = Eye disease associated with handling pet tarantulas: three case reports | journal=[[BMJ]] | volume=314 | pmid = 9183200 | issue=7093 | pmc=2126783 | pages=1524–5 | doi=10.1136/bmj.314.7093.1524 }}</ref>
Some setae are used to stridulate, which makes a hissing sound. These hairs are usually found on the chelicerae. [[Stridulation]] seems to be more common in old-world species.


Some setae are used to [[Stridulation|stridulate]], which makes a hissing sound. These bristles are usually found on the chelicerae. Stridulation seems to be more common in Old World species.
==Bites and urticating hairs==
[[File:Lasiodora parahybana, chelicerae 05.JPG|left|thumb|Lasiodora parahybana, [[chelicerae]] of an adult female]]
Though all tarantulas are venomous and some bites cause serious discomfort that might persist for several days, so far there is no record of a bite causing a human fatality. In general, the effects of the bites of all kinds of tarantula are not well known. While the bites of many species are known to be no worse than a wasp sting, accounts of bites by some species are reported to be very painful and to produce intense spasms that may recur over a period of several days; the venom by the African tarantula ''[[Pelinobius muticus]]'' also causes strong hallucinations.<ref>{{cite book|author=Klátil, Lubomír |title=Sklípkani: krasavci s chlupatýma nohama|url=http://books.google.com/books?id=LJPIAAAACAAJ|year=1998|publisher=Nakl. Kabourek Zlín|isbn=978-80-901466-5-5|page=40}}</ref> For Poecilotheria species, researchers have described more than 20 bites with the delayed onset of severe and diffuse muscle cramps that resolved completely with the use of benzodiazepines and magnesium. In all cases, it is advisable to seek medical aid. Because other proteins are included when a [[toxin]] is injected, some individuals may suffer severe symptoms due to an allergic reaction rather than to the venom. Such allergic effects can be life-threatening [Fuchs J. A verified spider bite and a review of the literature confirm Indian ornamental tree spiders (Poecilotheria species) as underestimated theraphosids of medical importance.[Toxicon. 2014, 77:73-7]


== Bites and urticating bristles ==
Before biting, tarantulas may signal their intention to attack by rearing up into a "threat posture", which may involve raising their prosoma and lifting their front legs into the air, spreading and extending their fangs, and (in certain species) making a loud hissing by [[stridulation|stridulating]]. Their next step, short of biting, may be to slap down on the intruder with their raised front legs. If that response fails to deter the attacker, the tarantulas of the Americas may next turn away and flick urticating hairs toward the pursuing predator. The next response may be to leave the scene entirely, but, especially if there is no line of retreat, their final response may also be to whirl suddenly and bite. Some tarantulas are well known to give "dry bites," i.e., they may defensively bite some animal that intrudes on their space and threatens them, but they will not pump venom into the wound.
[[File:Lasiodora parahybana, chelicerae 05.JPG|thumb|''L. parahybana'', [[chelicerae]] of an adult female]]
All tarantulas are venomous. Although their [[venom]] is not deadly to humans, some bites cause serious discomfort that might persist for several days. In general, the effects of the bites of all kinds of tarantula are not well known. While the bites of many species are known to be no worse than a wasp sting, accounts of bites by some species are reported to be very painful and to produce intense spasms that may recur over a period of several days; the [[venom]] of the African tarantula ''[[Pelinobius muticus]]'' also causes strong hallucinations.<ref>{{cite book|author=Klátil, Lubomír|title=Sklípkani: krasavci s chlupatýma nohama|url=https://books.google.com/books?id=LJPIAAAACAAJ|year=1998|publisher=Nakl. Kabourek Zlín|isbn=978-80-901466-5-5|page=40|url-status=live|archive-url=https://web.archive.org/web/20131231200356/http://books.google.com/books?id=LJPIAAAACAAJ|archive-date=31 December 2013}}</ref>{{request quotation |date=February 2019}}{{additional citation needed |reason=This sole citation is a Czech language book not available in the U.S. and without text available online. Also a fairly extraordinary claim, and one not currently mentioned in the ''Pelinobius muticus'' article. |date=February 2019}} For ''[[Poecilotheria]]'' species, researchers have described more than 20 bites with the delayed onset of severe and diffuse muscle cramps, lasting for several days, that in most cases resolved completely with the use of [[benzodiazepines]] and [[magnesium]]. In all cases, seeking medical aid is advised. Because other proteins are included when a [[toxin]] is injected, some individuals may suffer severe symptoms due to an [[Anaphylaxis|allergic reaction]] rather than to the venom. Such allergic effects can be life-threatening.{{citation needed|date=July 2014}} Additionally, the large fangs of a tarantula can inflict painful [[puncture wound]]s, which can lead to secondary [[bacterial infection]]s if not properly treated.


Before biting, a tarantula may signal its intention to attack by rearing up into a "threat posture", which may involve raising its prosoma and lifting its front legs into the air, spreading and extending its fangs, and (in certain species) making a loud hissing by [[Stridulation|stridulating]]. Tarantulas often hold this position for longer than the duration of the original threat. Their next step, without biting, may be to slap down on the intruder with their raised front legs. If that response fails to deter the attacker, the tarantulas of the Americas may next turn away and flick [[urticating hair]]s toward the pursuing predator. The next response may be to leave the scene entirely, but especially if no line of retreat is available, their final response may also be to whirl suddenly and bite. Some tarantulas are well known to give "dry bites", i.e., they may defensively bite some animal that intrudes on their space and threatens them, but they do not pump [[venom]] into the wound.
New-world tarantulas (those found in [[North America|North]] and [[South America]]) are equipped with [[urticating hair]]s on their abdomen, and will almost always [[projectile use by living systems|throw]] these barbed hairs as a first line of defense. These hairs will irritate sensitive areas of the body and especially seem to target curious animals who may sniff these hairs into the mucous membranes of the nose. Some species have more effective urticating hairs than others. The [[Goliath Birdeater]] is one species known for its particularly irritating urticating hairs. Urticating hairs can penetrate the [[cornea]] so eye protection should be worn when handling such tarantulas.<ref>[http://www.msnbc.msn.com/id/34647048/ns/health-pet_health/ Tarantula shoots sharp hairs into owner’s eye] MSNBC/LiveScience</ref>


New-world tarantulas—those indigenous to the Americas—have bites that generally pose little threat to humans (other than causing localized pain). Most of them are equipped with [[urticating hair]]s on their abdomens, and almost always throw these barbed bristles as the first line of defense. These bristles irritate sensitive areas of the body and especially seem to target curious animals that may sniff these bristles into the mucous membranes of the nose. Some species have more effective [[Urticating hair|urticating bristles]] than others. The [[goliath birdeater]] is known for its particularly irritating [[Urticating hair|urticating bristles]]. They can penetrate the [[cornea]], so eye protection should be worn when handling such tarantulas.<ref>[http://www.nbcnews.com/id/34647048 Tarantula shoots sharp bristles into owner's eye]{{dead link|date=August 2024|bot=medic}}{{cbignore|bot=medic}} NBC News/LiveScience</ref>
Old-world tarantulas (from Europe, Africa, Asia and Australia) have no urticating hairs and are more likely to attack when disturbed. Old-world tarantulas often have more potent, medically significant venom.


[[Old World]] tarantulas have no [[Urticating hair|urticating bristles]] and are more likely to attack when disturbed. They often have more potent, medically significant [[venom]], and are faster and much more nervous and defensive than [[New World]] species.
There are dangerous spider species which are related to tarantulas and frequently confused with them. A popular [[urban legend]] maintains that deadly varieties of tarantula exist somewhere in South America. This claim is often made without identifying a particular spider, although the "banana tarantula" is sometimes named. A likely candidate for the true identity of this spider is the dangerous [[Brazilian wandering spider]] ''Phoneutria nigriventer'', of the family [[wandering spider|Ctenidae]], as it is sometimes found hiding in clusters of bananas and is one of several spiders called the "banana spider." It is not technically a tarantula but it is fairly large (4&ndash;5&nbsp;inch legspan), somewhat hairy, and is highly venomous to humans. Another dangerous type of spider that has been confused with tarantulas is the [[Australasian funnel-web spider]]. The best known of these is the Sydney funnel-web spider ''Atrax robustus'', a spider that is aggressive, highly venomous, and (prior to the development of [[antivenin]] in the 1980s) was responsible for numerous deaths in [[Australia]]. These spiders are members of the same suborder as tarantulas. Some Australians use the slang term 'triantelope' (a corruption of the incorrect term 'tarantula', which is also used) for large, hairy and harmless members of the [[Huntsman spider]] family which are often found on interior household walls and in automobiles.<ref>[http://www.wonderbookofknowledge.com/huntsmanspiders.php Huntsman Spiders] at The Australian Wonder Book of Knowledge</ref>


Some dangerous spider species are related to tarantulas and are frequently confused with them. A popular [[urban legend]] maintains that deadly varieties of tarantula exist somewhere in [[South America]]. This claim is often made without identifying a particular spider, although the "banana tarantula" is sometimes named. A likely candidate for the true identity of this spider is the dangerous [[Brazilian wandering spider]] (''[[Phoneutria fera]]'') of the family [[Wandering spider|Ctenidae]], as it is sometimes found hiding in clusters of bananas and is one of several spiders called "banana spiders". It is not technically a tarantula, but it is fairly large (4- to 5-inch legspan), somewhat ″hairy″, and is highly [[venom]]ous to humans. Another dangerous type of [[spider]]s that have been confused with tarantulas are the [[Australian funnel-web spider]]s. The best known species of these is the [[Sydney funnel-web spider]] (''[[Atrax robustus]]'') a [[spider]] that is aggressive, highly [[venom]]ous, and (prior to the development of [[antivenom]] in the 1980s) was responsible for numerous deaths in [[Australia]]. These [[spider]]s are members of the same infraorder as tarantulas, [[Mygalomorphae]]. Some Australians use the slang term "triantelope" (a corruption of the incorrect term tarantula, which is also used) for large, ″hairy″, and harmless members of the [[huntsman spider]] family, which are often found on interior household walls and in automobiles.<ref>[http://www.wonderbookofknowledge.com/huntsmanspiders.php Huntsman Spiders] {{webarchive|url=https://web.archive.org/web/20090712003221/http://www.wonderbookofknowledge.com/huntsmanspiders.php |date=12 July 2009 }} at The Australian Wonder Book of Knowledge</ref>
==Medical implications==
While no fatalities have been attributed to [[Spider bite|tarantula bites]],{{cn|date=November 2013}} sometimes spider bites are regarded as the probable source of infections. Medical advice regarding [[prophylaxis]] may be helpful in that regard. In addition, there is considerable anecdotal evidence{{Citation needed|date=February 2011}} indicating that the venoms of some old-world species can produce symptoms so severe that medical treatment would be appropriate. Medical intervention is also regarded as appropriate when symptoms such as breathing difficulty or chest pain develop, since these conditions may indicate an [[anaphylaxis|anaphylactic]] reaction. As with [[bee sting]]s, allergic reactions to protein fractions may be many times more dangerous than the direct toxic effects of the venom.


== Sexual dimorphism ==
Urticating hairs may cause medical problems for humans when they enter the eyes or the respiratory system, but unless one inhales air heavily laden with these hairs or rubs them into one's eyes, they rarely are a problem. Some individuals are unusually sensitive to skin contact with the hairs and must avoid them in cleaning cages or similar activities.
Some tarantula species exhibit pronounced [[sexual dimorphism]]. Males tend to be smaller (especially their abdomens, which can appear quite narrow) and may be dull in color when compared to their female counterparts, as in the species ''[[Haplopelma lividum]]''. Mature male tarantulas also may have tibial hooks on their front legs, which are used to restrain the female's fangs during copulation. Males typically have longer legs than the females.


[[File:California ebony tarantula.jpg|thumb|Male California ebony tarantula (''[[Aphonopelma eutylenum]]'') wandering near Exeter, CA]]
==Sexual dimorphism==
Some tarantula species exhibit pronounced [[sexual dimorphism]]. Males tend to be smaller (especially their abdomens, which can appear quite narrow) and may be dull in color when compared to their female counterparts, as in the species ''Haplopelma lividum''. Mature male tarantulas also may have tibial hooks on their front legs, which are used to restrain the female's fangs during copulation.


A juvenile male's sex can be determined by looking at a cast [[exuvia|exuvium]] for [[exiandrous fusillae]] or [[spermathecae]]. Females possess spermathecae except for the species ''Sickius longibulbi'' and ''Encyocratella olivacea''.<ref name=Bertani2008>{{cite journal|author=[[Rogério Bertani|Bertani, R.]]; Fukushima, C.S. and Júnior, P.I.S. |year=2008|title=Mating behavior of Sickius longibulbi (Araneae, Theraphosidae, Ischnocolinae), a spider that lacks spermathecae|journal=The Journal of Arachnology|volume= 36|pages=331–335|url=http://birdspider.de/doc/Sickius-longibulbi-01.pdf|doi=10.1636/CSt07-100.1|issue=2}}</ref><ref name=Gallon2003>{{cite journal|author=Gallon, R. C. |year=2003|title= A new African arboreal genus and species of theraphosid spider (Araneae, Theraphosidae, Stromatopelminae) which lacks spermathecae|journal=The Bulletin of the British Arachnological Society|volume=12 |issue=9|pages=405–411|url=http://birdspider.de/doc/Encyocratella-olivacea-formerly-Xenodendrophila-gabrieli-01.pdf}}</ref> Ventral sexing is difficult, but, if done correctly, it can be relatively reliable. Males have much shorter lifespans than females because they die relatively soon after maturing. Few live long enough for a post-ultimate moult. It is unlikely that it happens much in natural habitats because they are vulnerable to predation, but it has happened in captivity if rarely. Most males do not live through this moult as they tend to get their emboli, mature male sexual organs on pedipalps, stuck in the moult. Most tarantula fanciers regard females as more desirable as pets due to their much longer lifespan. Wild caught tarantulas are often mature males because they wander out in the open and are more likely to be caught.
A juvenile male's sex can be determined by looking at a cast [[exuvia]] for [[epiandrous fusillae]] or [[spermathecae]]. Females possess [[spermatheca]]e, except for the species ''[[Sickius longibulbi]]'' and ''[[Encyocratella olivacea]]''.<ref name=Bertani2008>{{cite journal|author1-link=Rogério Bertani|last1=Bertani|first1=R.|last2=Fukushima|first2=C.S.|last3=Júnior|first3=P.I.S.|year=2008|title=Mating behavior of Sickius longibulbi (Araneae, Theraphosidae, Ischnocolinae), a spider that lacks spermathecae|journal=The Journal of Arachnology|volume= 36|issue=2|pages=331–335|url=http://birdspider.de/doc/Sickius-longibulbi-01.pdf|doi=10.1636/CSt07-100.1|s2cid=55978068}}</ref><ref name=Gallon2003>{{cite journal|author=Gallon, R. C. |year=2003|title= A new African arboreal genus and species of theraphosid spider (Araneae, Theraphosidae, Stromatopelminae) which lacks spermathecae|journal=Bulletin of the British Arachnological Society|volume=12 |issue=9|pages=405–411|url=http://birdspider.de/doc/Encyocratella-olivacea-formerly-Xenodendrophila-gabrieli-01.pdf}}</ref> Males have much shorter lifespans than females because they die relatively soon after maturing. Few live long enough for a postultimate [[Moulting|molt]], which is unlikely in natural habitats because they are vulnerable to predation, but has happened in captivity, though rarely. Most males do not live through this [[Moulting|molt]], as they tend to get their emboli, mature male sexual organs on [[pedipalp]]s, stuck in the [[Moulting|molt]]. Most tarantula fanciers regard females as more desirable as pets due to their much longer lifespans. Wild-caught tarantulas are often mature males because they wander out in the open and are more likely to be caught.


==Life cycle==
== Life cycle ==
[[File:A geniculata skin.gif|right|thumb|The molting process]]
Like other spiders, tarantulas have to shed their [[exoskeleton]] periodically as they grow, a process called [[Ecdysis|molting]]. A young tarantula may do this several times a year as a part of the maturation process, while full-grown specimens only molt once a year or less, or sooner, to replace lost limbs or lost [[urticating hair]]s. It is visibly apparent that molting is imminent when the [[exoskeleton]] takes on a darker shade. If a tarantula previously used its urticating hairs, the bald patch turns from a peach color to deep blue. The tarantula also stops feeding and becomes more lethargic during this time.


While most Tarantulas species take between two and five years to reach sexual maturity, some species can take up to 10 years. Upon reaching adulthood, males typically have an 18-month period left to live so immediately go in search of a female mate. Although females continue to molt after reaching maturity, males rarely do again once they reach adulthood. Those that do often can become stuck during the molting process due to their sexual organs and die.
[[Image:A geniculata skin.gif|right|thumb|The molting process]]
Like other spiders, tarantulas have to shed their [[exoskeleton]] periodically in order to grow, a process called [[ecdysis|molting]]. A young tarantula may do this several times a year as a part of the maturation process, while full grown specimens will only molt once a year or less, or sooner in order to replace lost limbs or lost urticating hairs. It is clear that molting will soon occur when the exoskeleton takes on a darker shade. If a tarantula previously used its urticating hairs, the bald patch will turn from a peach color to deep blue.


Females can live for 30 to 40 years.<ref name="Schultz">{{Cite book |last1=Schultz |first1=Stanley A. |title=The Tarantula Keeper's Guide |last2=Schultz |first2=Marguerite J. |publisher=Barron's Educational Series |year=1998 |isbn=0764100769 |page=75}}</ref> ''[[Grammostola rosea]]'' spiders, which eat once or twice a week, have lived up to 20 years in captivity.<ref>{{Cite web|url=http://animal-world.com/encyclo/reptiles/spiders/rosehairtarantula.php|title=Rose-haired Tarantula|last=Animal-World|website=Animal World|language=en|access-date=2017-02-13|url-status=live|archive-url=https://web.archive.org/web/20170111042025/http://animal-world.com/encyclo/reptiles/spiders/rosehairtarantula.php|archive-date=11 January 2017}}</ref> Some have survived on water alone for up to two years.<ref name="Schultz" />
Tarantulas may live for years; most species take two to five years to reach adulthood, but some species may take up to ten years to reach full maturity. Upon reaching adulthood, males typically have but a 1 to 1.5 year period left to live and will immediately go in search of a female with which to mate. Male tarantulas rarely molt again once they reach adulthood. The oldest spider,<!--male or female?--> according to ''[[Guinness World Records]]'', lived to be 49 years old.


=== Reproduction ===
Females will continue to molt after reaching maturity. Female specimens have been known to reach 30 to 40 years of age, and have survived on water alone for up to 2 years.<ref>Schultz, Stanley A. and Schultz, Marguerite J. (1998) ''The Tarantula Keeper's Guide'', Barron's Educational Series, ISBN 0764100769, p. 75</ref> ''[[Grammostola rosea]]'' spiders are renowned for going for long periods without eating.{{Citation needed|date=September 2010}}
[[File:Phormictopus cancerides cancerides, baby.JPG|thumb|The molted skin of a juvenile ''[[Phormictopus cancerides]] cancerides'' (second molting)]]
After reaching sexual maturity, a female tarantula normally mates and lays eggs once per year,<ref name="Ferretti">{{cite journal |last1=Ferretti |first1=Nelson |last2=Pérez-Miles |first2=Fernando |last3=González |first3=Alda |title=Historical relationships among Argentinean biogeographic provinces based on mygalomorph spider distribution data (Araneae: Mygalomorphae) |journal=Studies on Neotropical Fauna and Environment |date=13 May 2014 |volume=49 |issue=1 |page=2 |doi=10.1080/01650521.2014.903616 |bibcode=2014SNFE...49....1F |s2cid=85259715 |quote=Mygalomorph spiders are well-suited models for biogeographical analysis... They are long-lived and univoltine, and show high local endemicity.|hdl=11336/33878 |hdl-access=free }}</ref><ref name="Punzo">{{cite book |last1=Punzo |first1=Fred |title=Spiders: Biology, Ecology, Natural History, and Behaviour |publisher=Brill |date=2007 |isbn=9789004156647 |page=182}}</ref> although they do not always do so.<ref name="Punzo1999">{{cite journal |last1=Punzo |first1=Fred |title=Aspects of the natural history and behavioural ecology of the tarantula spider ''Aphonopelma hentzi'' (Girard, 1854) (Orthognatha, Theraphosidae) |journal=Bulletin of the British Arachnological Society |date=1999 |volume=11 |issue=4 |pages=122}}</ref>


As with other spiders, the mechanics of intercourse are quite different from those of [[mammal]]s. Once a male spider reaches maturity and becomes motivated to mate, he weaves a web mat on a flat surface. The spider then rubs his abdomen on the surface of this mat, and in so doing, releases a quantity of semen. He may then insert his [[pedipalp]]s (short, leg-like appendages between the [[chelicerae]] and front legs) into the pool of semen. The pedipalps absorb the semen and keep it viable until a mate can be found. When a male spider detects the presence of a female, the two exchange signals to establish that they are of the same species. These signals may also lull the female into a receptive state. If the female is receptive, then the male approaches her and inserts his pedipalps into an opening in the lower surface of her abdomen, the [[opisthosoma]]. After the semen has been transferred to the receptive female's body, the male swiftly leaves the scene before the female recovers her appetite. Although females may show some aggression after mating, the male rarely becomes a meal.{{Citation needed|date=March 2009}}<ref name="JHFLS" />
===Reproduction===


Females deposit 50 to 2,000 eggs, depending on the species, in a silken [[Spider|egg sac]] and guard it for six to eight weeks. During this time, the females stay very close to the egg sacs and become more aggressive. Within most species, the females turn the egg sac often, which is called brooding. This keeps the eggs from deforming due to sitting in one position too long. The young spiderlings remain in the nest for some time after hatching, where they live off the remains of their yolk sacs before dispersing.{{Citation needed|date=March 2009}}<ref>{{Cite news|url=http://www.livescience.com/39963-tarantula.html|title=Tarantula Facts|newspaper=Live Science|access-date=2017-02-13|url-status=live|archive-url=https://web.archive.org/web/20170213165004/http://www.livescience.com/39963-tarantula.html|archive-date=13 February 2017}}</ref>
[[File:Phormictopus cancerides cancerides, baby.JPG|left|thumb|The molted skin of a juvenile ''[[Phormictopus cancerides|Phormictopus cancerides cancerides]]'' (second molting)]]
As with other spiders, the mechanics of intercourse are quite different from those of mammals. Once a male spider reaches maturity and becomes motivated to mate, it will weave a web mat on a flat surface. The spider will then rub its abdomen on the surface of this mat and in so doing release a quantity of semen. It may then insert its pedipalps (short leg-like appendages between the chelicerae and front legs) into the pool of semen. The pedipalps absorb the semen and keep it viable until a mate can be found. When a male spider detects the presence of a female, the two exchange signals to establish that they are of the same species. These signals may also lull the female into a receptive state. If the female is receptive then the male approaches her and inserts his pedipalps into an opening in the lower surface of her abdomen, called the [[opisthosoma]]. After the semen has been transferred to the receptive female's body, the male will swiftly leave the scene before the female recovers her appetite. Although females may show some aggression after mating, the male rarely becomes a meal.{{Citation needed|date=March 2009}}


== Taxonomy ==
Females deposit 50 to 2000 eggs, depending on the species, in a silken egg sac and guard it for 6 to 8 weeks. During this time, the female will stay very close to the egg sac and become more aggressive. Within most species, the female turns the egg sac often, which is called brooding. This keeps the eggs from deforming due to sitting too long. The young spiderlings remain in the nest for some time after hatching where they live off the remains of their yolk sac before dispersing.{{Citation needed|date=March 2009}}
[[Carl Linnaeus|Linnaeus]] placed all spiders in a single genus, ''Aranea''. In 1802, [[Charles Athanase Walckenaer]] separated mygalomorph spiders into a separate genus, ''Mygale'', leaving all other [[spider]]s in ''[[Spider|Aranea]]''. However, ''Mygale'' had already been used in 1800 by [[Georges Cuvier]] for a genus of mammals (in [[Greek language|Greek]], ''mygale'' means "[[shrew]]"). Accordingly, in 1869, [[Tamerlan Thorell]] used the family name "Theraphosoidae" (modern Theraphosidae) for the [[Mygalomorphae|mygalomorph]] spiders known to him, rather than "Mygalidae" (as used, for example, by [[John Blackwall]]). Thorell later split the family into a number of genera, including ''Theraphosa''.<ref name=Thor69>{{Citation |last1=Thorell |first1=T. |date=1869 |title=On European spiders. Part I. Review of the European genera of spiders, preceded by some observations on zoological nomenclature |journal=Nova Acta Regiae Societatis Scientiarum Upsaliensis |volume=7 |pages=1–108 |series=Series 3 }}</ref><ref name=Thor70>{{Citation |last1=Thorell |first1=T. |date=1870 |title=On European spiders |journal=Nova Acta Regiae Societatis Scientiarum Upsaliensis |volume=7 |pages=109–242 |series=Series 3 }}</ref>


==Taxonomy==
=== Subfamilies ===
A 2019 [[phylogenomic]] study recognized 12 subfamilies, one (Ischnocolinae) known not to be [[Monophyly|monophyletic]].<ref name=FoleLuddChenKreh19>{{Citation |mode=cs1 |last1=Foley |first1=Saoirse |last2=Lüddecke |first2=Tim |last3=Cheng |first3=Dong-Qiang |last4=Krehenwinkel |first4=Henrik |last5=Künzel |first5=Sven |last6=Longhorn |first6=Stuart J. |last7=Wendt |first7=Ingo |last8=von Wirth |first8=Volker |last9=Tänzler |first9=Rene |last10=Vences |first10=Miguel |last11=Piel |first11=William H. |date=2019 |title=Tarantula phylogenomics: A robust phylogeny of deep theraphosid clades inferred from transcriptome data sheds light on the prickly issue of urticating setae evolution |journal=Molecular Phylogenetics and Evolution |volume=140 |issue=106573 |page=106573 |doi=10.1016/j.ympev.2019.106573 |pmid=31374259 |bibcode=2019MolPE.14006573F |s2cid=199389268 |name-list-style=amp }}</ref>
{{Main|List of Theraphosidae species}}
{{div col|colwidth=12em}}
The family Theraphosidae is divided into 12 [[family (biology)|subfamilies]], containing over 100 [[genus|genera]] and around 900 [[species]] between them.
*[[Aviculariinae]]
*[[Eumenophorinae]]
*[[Harpactirinae]]
*[[Ischnocolinae]]
*[[Ornithoctoninae]]
*[[Poecilotheriinae]]
*[[Psalmopoeinae]]
*[[Schismatothelinae]]
*[[Selenocosmiinae]]
*[[Stromatopelminae]]
*[[Theraphosinae]]
*[[Thrigmopoeinae]]
{{div col end}}
The relationship between the subfamilies found in the study is shown in the following [[cladogram]].<ref name=FoleLuddChenKreh19/> The dual placing of Ischnocolinae is highlighted.
{{clade
|label1=Theraphosidae
|1={{clade
|1={{clade
|1=<span style="background-color:#FF6">[[Ischnocolinae]]</span> (''[[Catamiri]]'' sp.)
|2=[[Eumenophorinae]]
}}
|2={{clade
|1={{clade
|1=[[Thrigmopoeinae]]
|2=[[Selenocosmiinae]]
}}
|2={{clade
|1={{clade
|1={{clade
|1=[[Poecilotheriinae]]
|2=[[Ornithoctoninae]]
}}
|2={{clade
|1=[[Stromatopelminae]]
|2=[[Harpactirinae]]
}}
}}
|2={{clade
|1=<span style="background-color:#FF6">[[Ischnocolinae]]</span> (''[[Trichopelma laselva]]'')
|label2="bombardier clade"
|2={{clade
|1={{clade
|1=[[Aviculariinae]]
|2={{clade
|1=[[Schismatothelinae]]
|2=[[Psalmopoeinae]]
}}
}}
|2=[[Theraphosinae]]
}}
}}
}}
}}
}}
}}
All the species that possess [[urticating hair]]s and have been seen to use them in bombardment behavior are placed in the "bombardier clade", although not all species in the included subfamilies possess such hairs (all ''[[Schismatothelinae]]'' lack them as do most ''[[Psalmopoeinae]]'' genera). It is not clear whether the possession of [[urticating hair]]s was an ancestral trait of the clade, and has been lost in some species, or whether it represents multiple gains. Foley ''et al.'' suggested that the second hypothesis appeared to be better supported.<ref name=FoleLuddChenKreh19/>


Other subfamilies that have been recognized include:{{citation needed|date=July 2019}}
*[[Acanthopelminae]], first described by [[Frederick Octavius Pickard-Cambridge]] in 1897, is a subfamily of small, terrestrial new-world tarantulas. This subfamily has only one genus, ''Acanthopelma'', and two species, ''A. beccarri'' and ''A. rufescens'', found in [[Guyana]] and [[Central America]].
*[[Acanthopelminae]] – may be treated as synonymous with Ischnocolinae
*[[Selenogyrinae]]
*[[Spelopelminae]] – typically not accepted, ''Hemirrhagus'' being treated as Theraphosinae


=== Genera ===
*[[Aviculariinae]] is a subfamily of tropical, tree-dwelling new-world tarantulas. They range from the [[Caribbean]] to [[South America]], and are commonly known as "pinktoe" tarantulas. The genera ''[[Avicularia]]'', ''Ephebopus'', and ''Pachistopelma'' possess urticating hairs, but cannot "flick" them into the air; instead the hairs are pressed into an enemy upon contact.
{{as of|2023|12}}, the [[World Spider Catalog]] accepted the following genera:<ref name=NMBE>{{cite web| title=Family: Theraphosidae Thorell, 1869| website=World Spider Catalog| access-date=2022-05-02| publisher=Natural History Museum Bern| url=http://www.wsc.nmbe.ch/family/100}}</ref>


{{div col|colwidth=25em}}
*[[Eumenophorinae]] is a subfamily of old-world tarantulas, mostly from [[Africa]] and surrounding regions. In addition, some authors place genus ''Proshapalopus'' (a genus found in [[Brazil]], and not in Africa) in this sub-family.
*''[[Abdomegaphobema]]'' <small>Sherwood, Gabriel, Peñaherrera-R., Léon-E., Cisneros-Heredia, Brescovit & Lucas, 2023</small>
*''[[Acanthopelma]]'' <small>F. O. Pickard-Cambridge, 1897</small> – Guyana
*''[[Acanthoscurria]]'' <small>Ausserer, 1871</small> – South America, Guatemala
*''[[Acentropelma]]'' <small>Pocock, 1901</small> – Belize, Mexico, Guatemala
*''[[Aenigmarachne]]'' <small>Schmidt, 2005</small> – Costa Rica
*''[[Agnostopelma]]'' <small>Pérez-Miles & Weinmann, 2010</small> – Colombia
*''[[Aguapanela (spider)|Aguapanela]]'' <small>Perafán & Cifuentes, 2015</small>
*''[[Amazonius (spider)|Amazonius]]'' <small>Cifuentes & Bertani, 2022</small> - South America
*''[[Annandaliella]]'' <small>Hirst, 1909</small> – India
*''[[Anoploscelus]]'' <small>Pocock, 1897</small> – Uganda, Tanzania, Rwanda
*''[[Anqasha]]'' <small>Sherwood & Gabriel, 2022</small> - Peru
*''[[Antikuna (spider)|Antikuna]]'' <small>Kaderka, Ferretti, West, Lüddecke & Hüsser, 2021</small> - Peru
*''[[Antillena]]'' <small>Bertani, Huff & Fukushima, 2017</small> – Dominican Republic
*''[[Aphonopelma]]'' <small>Pocock, 1901</small> – North America, Central America
*''[[Augacephalus]]'' <small>Gallon, 2002</small> – South Africa, Mozambique, Eswatini
*''[[Avicularia]]'' <small>Lamarck, 1818</small> – South America, Trinidad and Tobago, Panama
*''[[Bacillochilus]]'' <small>Gallon, 2010</small> – Angola
*''[[Batesiella]]'' <small>Pocock, 1903</small> – Cameroon
*''[[Bermejoa]]'' <small>Gabriel, Sherwood & Pérez-Miles, 2023</small>
*''[[Birupes]]'' <small>Gabriel & Sherwood, 2019</small> – Malaysia
*''[[Bistriopelma]]'' <small>Kaderka, 2015</small> – Peru
*''[[Bonnetina]]'' <small>Vol, 2000</small> – Mexico
*''[[Brachionopus]]'' <small>Pocock, 1897</small> – South Africa
*''[[Brachypelma]]'' <small>Simon, 1891</small> – Mexico, Costa Rica, Guatemala
*''[[Bumba (spider)|Bumba]]'' <small>Pérez-Miles, Bonaldo & Miglio, 2014</small> – Brazil, Venezuela, Ecuador
*''[[Cardiopelma]]'' <small>Vol, 1999</small> – Unknown
*''[[Caribena]]'' <small>Fukushima & Bertani, 2017</small> – Cuba
*''[[Catanduba]]'' <small>Yamamoto, Lucas & Brescovit, 2012</small> – Brazil
*''[[Catumiri]]'' <small>Guadanucci, 2004</small> – South America
*''[[Ceratogyrus]]'' <small>Pocock, 1897</small> – Africa
*''[[Chaetopelma]]'' <small>Ausserer, 1871</small> – Asia, Greece, Africa
*''[[Chilobrachys]]'' <small>Karsch, 1892</small> – Asia
*''[[Chinchaysuyu (spider)|Chinchaysuyu]]'' <small>Ferretti, Chaparro, Ochoa & West, 2023</small>
*''[[Chromatopelma]]'' <small>Schmidt, 1995</small> – Venezuela
*''[[Citharacanthus]]'' <small>Pocock, 1901</small> – Cuba, Central America, Mexico
*''[[Citharognathus]]'' <small>Pocock, 1895</small> – Indonesia
*''[[Clavopelma]]'' <small>Chamberlin, 1940</small> – Mexico
*''[[Coremiocnemis]]'' <small>Simon, 1892</small> – Malaysia, Indonesia, Australia
*''[[Cotztetlana]]'' <small>Mendoza, 2012</small> – Mexico
*''[[Crassicrus]]'' <small>Reichling & West, 1996</small> – Mexico, Belize
*''[[Cubanana]]'' <small>Ortiz, 2008</small> – Cuba
*''[[Cyclosternum]]'' <small>Ausserer, 1871</small> – South America, Mexico, Costa Rica
*''[[Cymbiapophysa]]'' <small>Gabriel & Sherwood, 2020</small>
*''[[Cyriocosmus]]'' <small>Simon, 1903</small> – South America, Trinidad and Tobago
*''[[Cyriopagopus]]'' <small>Simon, 1887</small> – Asia
*''[[Cyrtogrammomma]]'' <small>Pocock, 1895</small> - Guyana and Brazil
*''[[Cyrtopholis]]'' <small>Simon, 1892</small> – Caribbean
*''[[Davus]]'' <small>O. Pickard-Cambridge, 1892</small> – Central America, Mexico
*''[[Dolichothele]]'' <small>Mello-Leitão, 1923</small> – Brazil, Bolivia
*''[[Dugesiella]]'' <small>Pocock, 1901</small> - Mexico
*''[[Encyocratella]]'' <small>Strand, 1907</small> – Tanzania
*''[[Encyocrates]]'' <small>Simon, 1892</small> – Madagascar
*''[[Ephebopus]]'' <small>Simon, 1892</small> – Suriname, Brazil
*''[[Euathlus]]'' <small>Ausserer, 1875</small> – Chile, Argentina
*''[[Eucratoscelus]]'' <small>Pocock, 1898</small> – Kenya, Tanzania
*''[[Eumenophorus]]'' <small>Pocock, 1897</small> – Sierra Leone
*''[[Eupalaestrus]]'' <small>Pocock, 1901</small> – South America
*''[[Euphrictus]]'' <small>Hirst, 1908</small> – Cameroon, Congo
*''[[Euthycaelus]]'' <small>Simon, 1889</small> – Colombia, Venezuela
*''[[Grammostola]]'' <small>Simon, 1892</small> – South America
*''[[Guyruita]]'' <small>Guadanucci, Lucas, Indicatti & Yamamoto, 2007</small> – Brazil, Venezuela
*''[[Hapalopus]]'' <small>Ausserer, 1875</small> – South America, Panama
*''[[Hapalotremus]]'' <small>Simon, 1903</small> – Bolivia, Peru, Argentina
*''[[Haploclastus]]'' <small>Simon, 1892</small> – India
*''[[Haplocosmia]]'' <small>Schmidt & von Wirth, 1996</small> – Nepal
*''[[Harpactira]]'' <small>Ausserer, 1871</small> – South Africa, Namibia
*''[[Harpactirella]]'' <small>Purcell, 1902</small> – South Africa, Morocco
*''[[Hemirrhagus]]'' <small>Simon, 1903</small> – Mexico
*''[[Heterophrictus]]'' <small>Pocock, 1900</small> – India
*''[[Heteroscodra]]'' <small>Pocock, 1900</small> – Cameroon, Gabon, Congo
*''[[Heterothele]]'' <small>Karsch, 1879</small> – Africa, Argentina
*''[[Holothele]]'' <small>Karsch, 1879</small> – Caribbean, South America
*''[[Homoeomma]]'' <small>Ausserer, 1871</small> – South America
*''[[Hysterocrates]]'' <small>Simon, 1892</small> – Africa
*''[[Idiothele]]'' <small>Hewitt, 1919</small> – South Africa
*''[[Iridopelma]]'' <small>Pocock, 1901</small> – Brazil
*''[[Ischnocolus]]'' <small>Ausserer, 1871</small> – Africa, Asia, Brazil, Europe
*''[[Isiboroa]]'' <small>Gabriel, Sherwood & Pérez-Miles, 2023</small>
*''[[Kankuamo marquezi|Kankuamo]]'' <small>Perafán, Galvis & Pérez-Miles, 2016</small>
*''[[Kochiana]]'' <small>Fukushima, Nagahama & Bertani, 2008</small> – Brazil
*''[[Lampropelma]]'' <small>Simon, 1892</small> – Indonesia, Malaysia, Singapore
*''[[Lasiocyano]]'' <small>Galleti-Lima, Hamilton, Borges & Guadanucci, 2023</small> – Brazil
*''[[Lasiodora]]'' <small>C. L. Koch, 1850</small> – South America, Costa Rica
*''[[Lasiodorides]]'' <small>Schmidt & Bischoff, 1997</small> – Ecuador, Peru
*''[[Longilyra]]'' <small>Gabriel, 2014</small> – El Salvador
*''[[Loxomphalia]]'' <small>Simon, 1889</small> – Tanzania
*''[[Loxoptygus]]'' <small>Simon, 1903</small> – Ethiopia
*''[[Lyrognathus]]'' <small>Pocock, 1895</small> – Indonesia, India, Malaysia
*''[[Magnacarina]]'' <small>Mendoza, Locht, Kaderka, Medina & Pérez-Miles, 2016</small> – Mexico
*''[[Mascaraneus]]'' <small>Gallon, 2005</small> – Mauritius
*''[[Megaphobema]]'' <small>Pocock, 1901</small> – Costa Rica, Colombia, Ecuador
*''[[Melloina]]'' <small>Brignoli, 1985</small> – Panama, Venezuela
*''[[Melognathus]]'' <small>Chamberlin, 1917</small>
*''[[Metriopelma]]'' <small>Becker, 1878</small> – Mexico
*''[[Miaschistopus]]'' <small>Pocock, 1897</small> – Venezuela
*''[[Monocentropus]]'' <small>Pocock, 1897</small> – Yemen, Madagascar
*''[[Munduruku bicoloratum|Munduruku]]'' <small>Miglio, Bonaldo & Pérez-Miles, 2013</small>
*''[[Murphyarachne]]'' <small>Sherwood & Gabriel, 2022</small> - Peru
*''[[Mygalarachne]]'' <small>Ausserer, 1871</small> – Honduras
*''[[Myostola]]'' <small>Simon, 1903</small> – Gabon, Cameroon
*''[[Neischnocolus]]'' <small>Petrunkevitch, 1925</small> – Panama
*''[[Neoheterophrictus]]'' <small>Siliwal & Raven, 2012</small> – India
*''[[Neoholothele]]'' <small>Guadanucci & Weinmann, 2015</small> – Colombia, Trinidad and Tobago, Venezuela
*''[[Neostenotarsus]]'' <small>Pribik & Weinmann, 2004</small> – French Guiana
*''[[Nesiergus]]'' <small>Simon, 1903</small> – Seychelles
*''[[Nesipelma]]'' <small>Schmidt & Kovařík, 1996</small> – St. Kitts and Nevis
*''[[Nhandu]]'' <small>Lucas, 1983</small> – Brazil, Paraguay
*''[[Omothymus]]'' <small>Thorell, 1891</small> – Malaysia
*''[[Ornithoctonus]]'' <small>Pocock, 1892</small> – Myanmar, Thailand
*''[[Orphnaecus]]'' <small>Simon, 1892</small> – Papua New Guinea, Philippines
*''[[Ozopactus]]'' <small>Simon, 1889</small> – Venezuela
*''[[Pachistopelma]]'' <small>Pocock, 1901</small> – Brazil
*''[[Pamphobeteus]]'' <small>Pocock, 1901</small> – South America, Panama
*''[[Parvicarina]]'' <small>Galleti-Lima, Hamilton, Borges & Guadanucci, 2023</small>
*''[[Pelinobius]]'' <small>Karsch, 1885</small> – Kenya, Tanzania
*''[[Phlogiellus]]'' <small>Pocock, 1897</small> – Asia, Papua New Guinea
*''[[Phoneyusa]]'' <small>Karsch, 1884</small> – Africa
*''[[Phormictopus]]'' <small>Pocock, 1901</small> – Cuba, Argentina, Brazil
*''[[Phormingochilus]]'' <small>Pocock, 1895</small> – Indonesia
*''[[Phrixotrichus]]'' <small>Simon, 1889</small> – Chile, Argentina
*''[[Plesiopelma]]'' <small>Pocock, 1901</small> – South America
*''[[Plesiophrictus]]'' <small>Pocock, 1899</small> – India, Micronesia, Sri Lanka
*''[[Poecilotheria]]'' <small>Simon, 1885</small> – Sri Lanka, India
*''[[Proshapalopus]]'' <small>Mello-Leitão, 1923</small> – Brazil, Colombia
*''[[Psalistops]]'' <small>Simon, 1889</small> - Colombia and Venezuela
*''[[Psalmopoeus]]'' <small>Pocock, 1895</small> – Trinidad, South America, Central America, Mexico
*''[[Psednocnemis]]'' <small>West, Nunn & Hogg, 2012</small> – Malaysia, Indonesia
*''[[Pseudhapalopus]]'' <small>Strand, 1907</small> – South America, Trinidad
*''[[Pseudoschizopelma]]'' <small>Smith, 1995</small> - Mexico
*''[[Pterinochilus]]'' <small>Pocock, 1897</small> – Africa
*''[[Pterinopelma]]'' <small>Pocock, 1901</small> – Brazil
*''[[Reichlingia]]'' <small>Rudloff, 2001</small> – Belize
*''[[Reversopelma]]'' <small>Schmidt, 2001</small> – Ecuador or Peru
*''[[Sahydroaraneus]]'' <small>Mirza & Sanap, 2014</small> – India
*''[[Sandinista lanceolatum|Sandinista]]'' <small>Longhorn & Gabriel, 2019</small>
*''[[Schismatothele]]'' <small>Karsch, 1879</small> – Venezuela, Colombia
*''[[Schizopelma]]'' <small>F. O. Pickard-Cambridge, 1897</small> – Mexico
*''[[Scopelobates]]'' <small>Simon, 1903</small> – Dominican Republic
*''[[Selenocosmia]]'' <small>Ausserer, 1871</small> – Oceania, Asia
*''[[Selenogyrus]]'' <small>Pocock, 1897</small> – Côte d'Ivoire, Sierra Leone
*''[[Selenotholus]]'' <small>Hogg, 1902</small> – Australia
*''[[Selenotypus]]'' <small>Pocock, 1895</small> – Australia
*''[[Sericopelma]]'' <small>Ausserer, 1875</small> – Central America, Brazil, Mexico
*''[[Sickius]]'' <small>Soares & Camargo, 1948</small> – Brazil
*''[[Sphaerobothria]]'' <small>Karsch, 1879</small> – Costa Rica, Panama
*''[[Spinosatibiapalpus]]'' <small>Gabriel & Sherwood, 2020</small>
*''[[Stichoplastoris]]'' <small>Rudloff, 1997</small> – El Salvador, Costa Rica, Panama
*''[[Stromatopelma]]'' <small>Karsch, 1881</small> – Africa
*''[[Taksinus]]'' <small>Songsangchote, Sippawat, Khaikaew & Chomphuphuang, 2022</small> - Thailand
*''[[Tapinauchenius]]'' <small>Ausserer, 1871</small> – South America, Saint Vincent and the Grenadines
*''[[Tekoapora]]'' <small>Galleti-Lima, Hamilton, Borges & Guadanucci, 2023</small>
*''[[Thalerommata]]'' <small>Ausserer, 1875</small> — Colombia, Mexico
*''[[Theraphosa]]'' <small>Thorell, 1870</small> – South America
*''[[Thrigmopoeus]]'' <small>Pocock, 1899</small> – India
*''[[Thrixopelma]]'' <small>Schmidt, 1994</small> – Peru, Chile
*''[[Tliltocatl]]'' - Mexico, Costa Rica, Guatemala
*''[[Tmesiphantes]]'' <small>Simon, 1892</small> – Brazil
*''[[Trichognathella]]'' <small>Gallon, 2004</small> – South Africa
*''[[Trichopelma]]'' <small>Simon, 1888</small> – Caribbean, South America, Central America
*''[[Typhochlaena]]'' <small>C. L. Koch, 1850</small> – Brazil
*''[[Umbyquyra]]'' <small>Gargiulo, Brescovit & Lucas, 2018</small> – Bolivia, Brazil
*''[[Urupelma (spider)|Urupelma]]'' <small>Kaderka, Lüddecke, Řezáč, Řezáčová & Hüsser, 2023</small>
*''[[Vitalius]]'' <small>Lucas, Silva & Bertani, 1993</small> – Brazil, Argentina
*''[[Xenesthis]]'' <small>Simon, 1891</small> – Panama, Venezuela, Colombia
*''[[Yanomamius]]'' <small>Bertani & Almeida, 2021</small> – Brazil, Venezuela
*''[[Ybyrapora]]'' <small>Fukushima & Bertani, 2017</small> – Brazil
{{div col end}}


Former genera:
*[[Harpactirinae]] is a group of old-world tarantulas from [[Africa]], though smaller than Eumenophorinae. They are known as '''baboon spiders''' for their hairy legs and the thick black scorpulae at the end of their feet, which are said to resemble [[baboon]]s.
*''Ami'' <small>Pérez-Miles, 2008</small> → ''[[Neischnocolus]]''
*''Barropelma'' <small>Chamberlin, 1940</small> → ''[[Neischnocolus]]''
*''[[Eurypelmella]]'' <small>Strand, 1907</small>, ''[[nomen dubium]]''
*''Magulla'' <small>Simon, 1892</small> → ''[[Tmesiphantes]]''
*''Melloleitaoina'' <small>Gerschman & Schiapelli, 1960</small> → ''[[Tmesiphantes]]''


== Fossil record ==
*[[Ischnocolinae]] contains spiders from around the world.
Fossils of [[Mygalomorphae|mygalomorph]] spiders date back to the [[Triassic]].{{citation needed|date=March 2024}} One species assigned to the Theraphosidae is ''Protertheraphosa spinipes'', found in [[Burmese amber]], which is dated to the mid and late Cretaceous.<ref name=Wund20>{{Cite journal |last1=Wunderlich |first1=J. |last2=Müller |first2=Patrick |date=2020 |title=New and already described fossil spiders (Araneae) of 20 families in mid and late Cretaceous Burmese amber with notes on spider phylogeny, evolution and classification |journal=Beiträge zur Araneologie |volume=13 |pages=22–164 |url=http://www.joergwunderlich.de/Downloads/Beitr._Araneol._Band_13_(2020).pdf |access-date=2024-03-28 }} pp. 43–45.</ref>


== See also ==
*The "earth tigers" of subfamily [[Ornithoctoninae]] form a group of old-world tarantulas which are found primarily in [[Southeast Asia]], southern [[China]], and [[Borneo]]. This group includes the infamous [[Chinese bird spider]].
<!--Alphabetical order, please.-->
* [[Cultural depictions of spiders]]
* [[Guangxitoxin]]
* [[Spider bite]]
* [[Spider taxonomy]]


== References ==
*[[Poecilotheria|Poecilotheriinae]] are tree spiders from [[Fauna of India|India]] and Sri Lanka, some of which are considered [[endangered species|endangered]]. This subfamily contains only a single genus.
{{Reflist|refs=
<ref name=EstrCame12>{{Citation |mode=cs1 |last1=Estrada-Alvarez |first1=Julio C. |last2=Cameron |first2=H.D. |date=2012 |title=Etymological origins of the generic names of Mexican tarantulas (Araneae:Theraphosidae) |journal=Revista Ibérica de Aracnología |issue=21 |pages=153–160 |url=https://www.researchgate.net/publication/320839094 |access-date=2019-10-10 |name-list-style=amp }}</ref>


<ref name=Foel92>{{Citation |mode=cs1 |last1=Foelix |first1=Rainer F. |date=1992 |title=Biologie der Spinnen |location=Stuttgart |publisher=Georg Thieme |isbn=3-13-575802-8 |page=17 |language=de }}</ref>
*[[Selenocosmiinae]] is a subfamily which consists mainly of tarantulas from East Asia and [[Australia]]. Like the East Asian tarantulas in [[Ornithoctoninae]], these are known for their strong venom and defensive disposition. The genera ''Psalmopoeus'' and ''Tapinauchenius'' do not have urticating hairs, unusual among new-world species.


<ref name=Koch50>{{Citation |mode=cs1 |last1=Koch |first1=C.L. |date=1850 |title=Übersicht des Arachnidensystems, Heft 5 |location=Nürnberg |publisher=J.L. Lotzbeck |doi=10.5962/bhl.title.39561|page=73 |language=de |url=https://www.biodiversitylibrary.org/itempdf/87778 |doi-access=free }}</ref>
*[[Selenogyrinae]] is a subfamily of tarantulas from India and Africa.


<ref name=Poco01>{{Citation |mode=cs1 |last1=Pocock |first1=R.I. |date=1901 |title=Some new and old genera of S.-American Avicularidae |journal=Annals and Magazine of Natural History |series=7th Series |volume=8 |issue=48 |pages=540–555 |doi=10.1080/03745480109443359 |url=https://zenodo.org/record/1430516 }}</ref>
*[[Stromatopelminae]] are tree-dwelling tarantulas from west and central Africa.


<ref name=Schm94>{{Citation |mode=cs1 |last1=Schmerler |first1=Johann Adam |date=1794 |title=Lateinisch-deutsches und deutsch lateinisches Wörterbuch 3. Aufl, Volume 2 |location=Erlangen |publisher=J.J. Palm |oclc=669374426 |url=https://books.google.com/books?id=n_ROAAAAcAAJ&pg=PA2401 |access-date=2019-10-10 |page=2402 |language=de, la}}</ref>
*[[Theraphosinae]] are new-world terrestrial tarantulas with [[urticating hair]]s. The majority of spiders kept as pets are of this sub-family, including ''[[Brachypelma]]'', a genus of tropical new-world species generally considered docile and good starter species by those who keep tarantulas as pets.
}}


== Further reading ==
*[[Thrigmopoeinae]] are [[Fauna of India|India]]n tarantulas.
* {{Cite journal |author1=S. B. Reichling |author2=R. C. West |name-list-style=amp |year=1996 |title=A new genus and species of theraphosid spider from Belize (Araneae, Theraphosidae) |journal=Journal of Arachnology |volume=24 |pages=254–261 |url=http://www.americanarachnology.org/JoA_free/JoA_V24_n3/JoA_v24_p254.pdf}}
* {{Cite journal |author=Raven R. R. |author-link=Robert Raven |year=2005 |title=A new tarantula species from northern Australia (Araneae, Theraphosidae) |journal=[[Zootaxa]] |volume=1004 |pages=15–28 |doi=10.11646/zootaxa.1004.1.2 |url=http://www.mapress.com/zootaxa/2005f/zt01004p028.pdf}}


== External links ==
A few genera are presently not well classified, and/or have classifications which are disputed, including ''Brachionopus''.
{{Wikispecies|Theraphosidae}}

==Fossil record==
Although there are fossils of mygalomorph spiders going back to the [[Triassic]], only two specimens have been found so far which can be convincingly assigned to Theraphosidae. One is from Dominican Republic amber, the other from Chiapas (Mexican) amber. Both these ambers are quite young, being [[Miocene]] in age or about 16 million years old.

==Eating Tarantula==
Cambodians from Skuon began eating tarantulas during the years of food shortage under the Khmer Rogue. But even as starvation became less and less common, tarantulas remained a part of that region’s cuisine. Apparently, tarantulas are crispy on the outside with white meat in the head and body and taste vaguely like chicken or cod.<ref>[http://wikitravelbook.com/?page=artreader&id=80 10 Weird asian foods]</ref>

==See also==
<!--Alphabetical order, please.-->
* [[Cultural depictions of spiders]]
* [[Guangxitoxin]]
* [[List of spiders associated with cutaneous reactions]]
* [[List of Theraphosidae species]]
* [[Spider families]]
* [[Tarantula bites]]
* [[Tarantula hawk]] ([[wasp]] that feeds on tarantulas)

==References==
{{Reflist|35em}}

==Further reading==
*{{Cite journal |author=S. B. Reichling & R. C. West |year=1996 |title=A new genus and species of theraphosid spider from Belize (Araneae, Theraphosidae) |journal=Journal of Arachnology |volume=24 |pages=254–261 |url=http://www.americanarachnology.org/JoA_free/JoA_V24_n3/JoA_v24_p254.pdf|format=PDF}}
*{{Cite journal |author=[[Robert Raven|Raven R. R.]] |year=2005 |title=A new tarantula species from northern Australia (Araneae, Theraphosidae) |journal=[[Zootaxa]] |volume=1004 |pages=15–28 |url=http://www.mapress.com/zootaxa/2005f/zt01004p028.pdf|format=PDF}}
* [[Norman I. Platnick|Platnick N I]] (eds Merrett P and Cameron H D) [http://research.amnh.org/entomology/spiders/catalog/THERAPHOSIDAE.html Theraphosidae in The World Spider Catalog] Current online compilation, American Museum of Natural History, New York

==External links==
{{wikispecies|Theraphosidae}}
{{Commons category|Theraphosidae}}
{{Commons category|Theraphosidae}}
{{Wikisource|The Life of the Spider|The Life of the Spider}}
*[http://www.tarantulaforum.com/ TarantulaForum.com]
* [http://www.tarantulaforum.com/ TarantulaForum.com]
*{{dmoz|Recreation/Pets/Exotic/Invertebrates/Arthropods/Tarantulas|Tarantulas}}
*[http://www.tarantulasus.com/ Tarantulas US Forum]
* [http://www.tarantulasus.com/ Tarantulas US Forum] {{Webarchive|url=https://web.archive.org/web/20140228110156/http://www.tarantulasus.com/ |date=28 February 2014 }}
*[http://podictionary.com/?p=2011 Word of the Day: Tarantula and Tarantella], etymology and folklore
* [http://podictionary.com/?p=2011 Word of the Day: Tarantula and Tarantella], etymology and folklore
*[http://www.eightlegs.org/species.html Overview of Species Information for All Named Theraphosidae Divided by Subfamily]
* [http://www.eightlegs.us/species.html Overview of Species Information for All Named Theraphosidae Divided by Subfamily] {{Webarchive|url=https://web.archive.org/web/20210225130502/http://www.eightlegs.us/species.html |date=25 February 2021 }}
*[http://research.amnh.org/entomology/spiders/catalog/THERAPHOSIDAE.html Listing of all currently named Theraphosidae]
* [http://research.amnh.org/entomology/spiders/catalog/THERAPHOSIDAE.html Listing of all currently named Theraphosidae]
* [http://www.atshq.org/ American Tarantula Society Headquarters]
*[http://www.care-sheet.com/index/Theraphosidae Care for commonly kept Tarantula Pets]
* [https://web.archive.org/web/20140502213716/http://www.amazingtarantulas.com/ Amazing Tarantulas]
*[http://www.atshq.org/ American Tarantula Society Headquarters]
* {{cite web| url= http://aces.nmsu.edu/academics/spiders/| title=The Spiders of the Arid Southwest|author1=NMSU Entomology Plant Pathology |author2=Weed Science |name-list-style=amp | access-date=2013-07-15}}
*[http://www.amazingtarantulas.com/ Amazing Tarantulas]
* [https://web.archive.org/web/20101106062846/http://www.bbc.co.uk/nature/family/Tarantula Watch Tarantula (Theraphosidae) video clips from the BBC archive on Wildlife Finder]
*{{cite web| url= http://aces.nmsu.edu/academics/spiders/| title=The Spiders of the Arid Southwest| author=NMSU Entomology Plant Pathology and Weed Science| accessdate=2013-07-15}}
* [https://web.archive.org/web/20150914225302/http://www.theraphosidae.be/ Theraphosidae Belgium, everything about bird eaters]
*[http://www.bbc.co.uk/nature/family/Tarantula Watch Tarantula (Theraphosidae) video clips from the BBC archive on Wildlife Finder]
* [http://rdcu.be/AW6U]

{{Araneae}}
{{Araneae}}
{{Taxonbar|from=Q213383}}
{{Authority control}}


[[Category:Theraphosidae| ]]
[[Category:Theraphosidae| ]]
[[Category:Venomous spiders]]
[[Category:Extant Miocene first appearances]]

Latest revision as of 18:17, 3 December 2024

Tarantula
Temporal range: Cretaceous–present
Tliltocatl vagans
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Mygalomorphae
Clade: Avicularioidea
Family: Theraphosidae
Thorell, 1869
Diversity[1]
166 genera, 1,100 species

Tarantulas comprise a group of large and often hairy spiders of the family Theraphosidae.[2] As of December 2023, 1,100 species have been identified, with 166 genera.[3] The term "tarantula" is usually used to describe members of the family Theraphosidae, although many other members of the same infraorder (Mygalomorphae) are commonly referred to as "tarantulas" or "false tarantulas". Some of the more common species have become popular in the exotic pet trade. Many New World species kept as pets have setae known as urticating hairs that can cause irritation to the skin, and in extreme cases, cause damage to the eyes.[4]

Overview

Like all arthropods, the tarantula is an invertebrate that relies on an exoskeleton for muscular support.[5] Like other Arachnida, a tarantula's body comprises two main parts, the prosoma (or cephalothorax) and the opisthosoma (or abdomen). The prosoma and opisthosoma are connected by the pedicel, or pregenital somite. This waist-like connecting piece is actually part of the prosoma and gives the opisthosoma a wide range of motion relative to the prosoma.

Depending on the species, the body length of tarantulas ranges from about 5 to 11 cm (2 to 4+12 in)[6] with leg spans of 8–30 cm (3–12 in).[citation needed] Leg span is determined by measuring from the tip of the back leg to the tip of the front leg on the opposite side. Some of the largest species of tarantula may weigh over 85 g (3 oz); the largest of all, the goliath birdeater (Theraphosa blondi) from Venezuela and Brazil, has been reported to attain a weight of 170 g (6 oz)[7] and a leg-span up to 30 cm (12 in), males being longer and females greater in girth. The fang size of this tarantula reaches a maximum of 4 cm (1+12 in).[7]

Opening to a tarantula burrow

Theraphosa apophysis (the pinkfoot goliath) was described 187 years after the goliath birdeater, so its characteristics are not as well attested. T. blondi is generally thought to be the heaviest tarantula, and T. apophysis has the greatest leg span. Two other species, Lasiodora parahybana (the Brazilian salmon birdeater) and Lasiodora klugi, rival the size of the two goliath spiders.

Tarantula at the mouth of its burrow

Most species of North American tarantulas are brown. Elsewhere, species have been found that variously display cobalt blue (Cyriopagopus lividus), black with white stripes (Aphonopelma seemanni), yellow leg markings (Eupalaestrus campestratus), metallic blue legs with vibrant orange abdomen and green prosoma (Chromatopelma cyaneopubescens). Their natural habitats include savanna, grassland such as in the pampas, rainforest, desert, scrubland, mountains, and cloud forest. They are generally classed among the terrestrial types. They are burrowers that live in the ground.

Tarantulas are becoming increasingly popular as pets and some species are readily available in captivity.

Identification

Tarantulas can be confused with other members of the order Mygalomorphae, such as trapdoor spiders, funnel-web spiders and purseweb spiders. They can also be confused with some members of the order Araneomorphae such as the Lycosidae family. There are multiple ways to identify a tarantula. First the hairs: in the Americas most tarantulas have urticating hairs, though some, such as the Hemirrhagus genus, lack these. The hairs are usually more noticeable than with most other spiders. Another is the size, as tarantulas tend to be bigger, but this is again not a failproof way. They also do not use their webs for hunting, instead using them as building material or tripwire.[8]

One of the most decisive ways to tell is by looking at their fangs. Tarantula fangs face downwards, as opposed to those of true spiders, which face each other, allowing them to make pincerlike motions. They also own two book lungs, as opposed to true spiders which only have one. Their lifespan is also longer than most spiders.[8]

A tarantula next to a U.S. size 11 shoe, to show scale, taken near Austin, Texas

Etymology

The spider originally bearing the name tarantula was Lycosa tarantula, a species of wolf spider native to Mediterranean Europe.[9] The name is derived from the southern Italian town of Taranto.[10] The term tarantula was subsequently applied to almost any large, unfamiliar species of ground-dwelling spider, in particular to the Mygalomorphae and especially the New World Theraphosidae. Compared to tarantulas, wolf spiders are not particularly large or hairy, and so among English speakers in particular, usage eventually shifted in favour of the Theraphosidae, even though they are not closely related to wolf spiders at all, being in a different infraorder.

Tarantula native to the Mojave Desert searches for burrow.
Aphonopelma mojave, a tarantula native to the Mojave Desert, searches for a burrow.

The name tarantula is also incorrectly applied to other large-bodied spiders, including the purseweb spiders or atypical tarantulas, the funnel-webs (Dipluridae and Hexathelidae), and the dwarf tarantulas. These spiders are related to tarantulas (all being mygalomorphs) but fall into different families from them. Huntsman spiders of the family Sparassidae have also been termed tarantulas because of their large size, when, in fact, they are not related. Instead, huntsman spiders belong to the infraorder Araneomorphae.

The element pelma in genus names

Many theraphosid genera have names, either accepted or synonymous, containing the element pelma. This can be traced back to Carl Ludwig Koch in 1850,[11] who in describing his new genus Eurypelma wrote, "Die Sammetbürste der Fussohlen sehr breit" (lit.'the velvet-brush of the footsole very wide').[12] German arachnologists use the word Fuß to refer to the tarsus (the last article of a spider's leg).[13] Translations of Sammetbürste into Latin use the word scopula.[14] Hence in English arachnological terminology, Koch meant 'the scopula of the base of the tarsus very wide'. Eury- is derived from the Greek eurýs (εὐρύϛ), meaning 'wide', while pélma (πέλμα) means 'the sole of the foot',[11] paralleling Koch's use of Fußsohle (in modern spelling). Thus Eurypelma literally means 'wide footsole'; however, arachnologists have conventionally taken pelma in such names to refer to the scopula, so producing the meaning 'with a wide scopula'.[11]

Other genus names or synonyms that Estrada-Alvarez and Cameron regard as having 'footsole' or 'scopula' meanings include:[11]

Later, particularly following genus names published by R.I. Pocock in 1901,[15] the element pelma appears to have become synonymous with 'theraphosid'. For example, the author of Cardiopelma writes, "Cardiopelma fait réference aux genitalia de la femelle qui évoquent la forme d'un Coeur" ('Cardiopelma refers to the female genitalia that evoke the shape of a heart'), with no reference to either 'footsole' or 'scopula'. Names interpreted in this way include:[11]

  • Aphonopelma – Greek áphonos (ἄφωνοϛ) 'soundless'; overall meaning 'theraphosid without sound'
  • Cardiopelma – Greek cardía (καρδία) 'heart'; overall meaning 'heart theraphosid' (referring to the heart-shaped female genitalia)
  • Clavopelma – Latin clavis 'club'; overall meaning 'theraphosid with club-shaped hairs'
  • Delopelma – Greek delós (δηλόϛ) 'clear, obvious, visible, conspicuous, plain'; overall meaning 'theraphosid without plumose hair'
  • Gosipelma – the element gosi- means 'desert', relating to the Gosiute people; overall meaning 'desert theraphosid'
  • Spelopelma – Greek spélaion (σπήλαιον) 'cave'; overall meaning 'cave theraphosid'

Distribution

Tarantulas of various species occur throughout the United States, Mexico, in Central America, and throughout South America. Other species occur variously throughout Africa, much of Asia (including the Ryukyu Islands in southern Japan), and all of Australia. In Europe, some species occur in Spain, Portugal, Turkey, southern Italy, and Cyprus.

Habits

Some genera of tarantulas hunt prey primarily in trees; others hunt on or near the ground. All tarantulas can produce silk; while arboreal species typically reside in a silken "tube tent", terrestrial species line their burrows with silk to stabilize the burrow wall and facilitate climbing up and down. Tarantulas mainly eat large insects and other arthropods such as centipedes, millipedes, and other spiders, using ambush as their primary method of prey capture. Armed with their massive, powerful chelicerae tipped with long, chitinous fangs, tarantulas are well-adapted to killing other large arthropods. The biggest tarantulas sometimes kill and consume small vertebrates such as lizards, mice, bats, birds, and small snakes.

Appendages

Subadult female Poecilotheria regalis

The eight legs, the two chelicerae with their fangs, and the pedipalps are attached to the prosoma. The chelicerae are two double-segmented appendages located just below the eyes and directly forward of the mouth. The chelicerae contain the venom glands that vent through the fangs. The fangs are hollow extensions of the chelicerae that inject venom into prey or animals that the tarantula bites in defense, and they are also used to masticate. These fangs are articulated so that they can extend downward and outward in preparation to bite or can fold back toward the chelicerae as a pocket knife blade folds back into its handle. The chelicerae of a tarantula completely contain the venom glands and the muscles that surround them, and can cause the venom to be forcefully injected into prey.

The pedipalpi are two six-segmented appendages connected to the prosoma near the mouth and protruding on either side of both chelicerae. In most species of tarantulas, the pedipalpi contain sharp, jagged plates used to cut and crush food often called the coxae or maxillae. As with other spiders, the terminal portions of the pedipalpi of males function as part of their reproductive system. Male spiders spin a silken platform (sperm web) on the ground onto which they release semen from glands in their opisthosoma. Then they insert their pedipalps into the semen, absorb the semen into the pedipalps, and later insert the pedipalps (one at a time) into the reproductive organ of the female, which is located in her abdomen. The terminal segments of the pedipalps of male tarantulas are moderately larger in circumference than those of a female tarantula. Male tarantulas have special spinnerets surrounding the genital opening. Silk for the sperm web of the tarantula is exuded from these special spinnerets.

Claws at the end of the leg of Lasiodora parahybana
A Brazilian tarantula in defensively threatening position

A tarantula has four pairs of legs and two additional pairs of appendages. Each leg has seven segments, which from the prosoma out are: coxa, trochanter, femur, patella, tibia, tarsus and pretarsus, and claw. Two or three retractable claws at the end of each leg are used to grip surfaces for climbing. Also on the end of each leg, surrounding the claws, is a group of bristles, called the scopula, which help the tarantula to grip better when climbing surfaces such as glass. The fifth pair is the pedipalps, which aid in feeling, gripping prey, and mating in the case of a mature male. The sixth pair of appendages is the chelicerae and their attached fangs. When walking, a tarantula's first and third legs on one side move at the same time as the second and fourth legs on the other side of its body. The muscles in a tarantula's legs cause the legs to bend at the joints, but to extend a leg, the tarantula increases the pressure of haemolymph entering the leg.

Tarantulas, like almost all other spiders, have their primary spinnerets at the end of the opisthosoma. Unlike most spider species in the infraorder Araneomorphae, which includes the majority of extant spider species, and most of which have six, tarantula species have two or four spinnerets. Spinnerets are flexible, tube-like structures from which the spider exudes its silk. The tip of each spinneret is called the spinning field. Each spinning field is covered by as many as 100 spinning tubes through which silk is exuded. As the silk is pulled out of the spinnerets, the shear forces cause proteins in the silk to crystallize, transforming it from a liquid to a solid thread.

Digestive system

Tarantula food leftovers
Eye ports seen in an exuvia (molted skin)

The tarantula's mouth is located under its chelicerae on the lower front part of its prosoma. The mouth is a short, straw-shaped opening that can only suck, meaning that anything taken into it must be in liquid form. Prey with large amounts of solid parts, such as mice, must be crushed and ground up or predigested, which is accomplished by coating the prey with digestive juices secreted from openings in the chelicerae.

The tarantula's digestive organ (stomach) is a tube that runs the length of its body. In the prosoma, this tube is wider and forms the sucking stomach. When the sucking stomach's powerful muscles contract, the stomach is increased in cross-section, creating a strong sucking action that permits the tarantula to suck its liquefied prey up through the mouth and into the intestines. Once the liquefied food enters the intestines, it is broken down into particles small enough to pass through the intestine walls into the hemolymph (blood stream), where it is distributed throughout the body. After feeding, the leftovers are formed into a small ball by the tarantula and thrown away. In a terrarium, they often put them into the same corner.[16]

Nervous system

A tarantula's central nervous system (brain) is located in the bottom of the inner prosoma. A tarantula perceives its surroundings primarily via sensory organs called setae (bristles or spines, sometimes referred to as hairs). Although a tarantula has eight eyes like most spiders, touch is its keenest sense, and in hunting, it primarily depends on vibrations given off by the movements of its prey. A tarantula's setae are very sensitive organs and are used to sense chemical signatures, vibrations, wind direction, and possibly even sound. Tarantulas are also very responsive to the presence of certain chemicals such as pheromones.

Close-up of a tarantula's eyes

The eyes are located above the chelicerae on the forward part of the prosoma. They are small and usually set in two rows of four. Most tarantulas are not able to see much more than light, darkness, and motion. Arboreal tarantulas generally have better vision compared with terrestrial tarantulas.

Respiratory system

All types of tarantulas have two sets of book lungs (breathing organs); the first pair is located in a cavity inside the lower front part of the abdomen near where the abdomen connects to the cephalothorax, and the second pair is slightly farther back on the abdomen. Air enters the cavity through a tiny slit on each side of and near the front of the abdomen. Each lung consists of 15 or more thin sheets of folded tissue arranged like the pages of a book. These sheets of tissue are supplied by blood vessels. As air enters each lung, oxygen is taken into the blood stream through the blood vessels in the lungs. Needed moisture may also be absorbed from humid air by these organs.

Circulatory system

Thermal image of an ectothermic tarantula on an endothermic human hand

A tarantula's blood is unique (not only in appearance); an oxygen-transporting protein is present (the copper-based hemocyanin), but not enclosed in blood cells such as the erythrocytes of mammals. A tarantula's blood is not true blood, but rather a liquid called hemolymph (or haemolymph). At least four types of hemocytes, or hemolymph cells, are known.

The tarantula's heart is a long, slender tube located along the top of the opisthosoma. The heart is neurogenic as opposed to myogenic, so nerve cells instead of muscle cells initiate and coordinate the heart. It pumps hemolymph to all parts of the body through open passages often referred to as sinuses, and not through a circular system of blood vessels. If the exoskeleton is breached, loss of hemolymph will kill the spider unless the wound is small enough that the hemolymph can dry and close it.

Predators

Despite their large size and fearsome appearance and reputation, tarantulas themselves are prey for many other animals. The most specialized of these predators are large members of the wasp family Pompilidae such as the wasp Hemipepsis ustulata. These wasps are called "tarantula hawks". The largest tarantula hawks, such as those in the genus Pepsis, track, attack, and kill large tarantulas. They use olfaction to find the lair of a tarantula. The wasp must deliver a sting to the underside of the spider's cephalothorax, exploiting the thin membrane between the basal leg segments. This paralyzes the spider, and the wasp then drags it back into its burrow before depositing an egg on the prey's abdomen. The wasp then seals the spider in its burrow and flies off to search for more hosts. The wasp egg hatches into a larva and feeds on the spider's inessential parts, and as it approaches pupation, it consumes the remainder.[17] Other arthropods, such as large scorpions and giant centipedes, are also known to prey on tarantulas.[18]

Tarantulas are also preyed upon by a wide variety of vertebrates. Many of these, including lizards, frogs, birds, snakes and mammals, are generalist predators of all kinds of large arthropods. Mammals that have been known to prey on tarantulas, such as the coati, kinkajou, and opossum in the New World, and mongooses and the honey badger in the Old World, are often immune to the venom of their arthropod prey.

Humans also consume tarantulas for food in their native ranges. They are considered a delicacy in certain cultures (e.g. Venezuela[19] and Cambodia). They can be roasted over an open fire to remove the bristles (described further below) and then eaten.

Fried tarantula in a Cambodian restaurant

Tarantulas have evolved specialized bristles, or setae, to defend themselves against predators. Besides the normal bristles covering the body, some tarantulas also have a dense covering of irritating bristles called urticating hairs, on the opisthosoma, that they sometimes use as protection against enemies.[20] These bristles are present on most New World species, but not on any specimens from the Old World. Urticating hairs are usually kicked off the abdomen by the tarantula, but some may simply rub the abdomen against the target, like the genus Avicularia. These fine bristles are barbed and serve to irritate. They can be lethal to small animals such as rodents. Some people are sensitive to these bristles, and develop serious itching and rashes at the site. Exposure of the eyes and respiratory system to urticating hairs should be strictly avoided. Species with urticating hairs can kick these bristles off; they are flicked into the air at a target using their back pairs of legs. Tarantulas also use these bristles for other purposes, such as to mark territory or to line their shelters (the latter such practice may discourage flies from feeding on the spiderlings). Urticating hairs do not grow back, but are replaced with each molt. The intensity, number, and flotation of the bristles depends on the species of tarantula.

To predators and other enemies, these bristles can range from being lethal to simply being a deterrent. With humans, they can cause irritation to eyes, nose, and skin, and more dangerously, the lungs and airways, if inhaled. The symptoms range from species to species, from person to person, from a burning itch to a minor rash. In some cases, tarantula bristles have caused permanent damage to human eyes.[4]

Some setae are used to stridulate, which makes a hissing sound. These bristles are usually found on the chelicerae. Stridulation seems to be more common in Old World species.

Bites and urticating bristles

L. parahybana, chelicerae of an adult female

All tarantulas are venomous. Although their venom is not deadly to humans, some bites cause serious discomfort that might persist for several days. In general, the effects of the bites of all kinds of tarantula are not well known. While the bites of many species are known to be no worse than a wasp sting, accounts of bites by some species are reported to be very painful and to produce intense spasms that may recur over a period of several days; the venom of the African tarantula Pelinobius muticus also causes strong hallucinations.[21][need quotation to verify][additional citation(s) needed] For Poecilotheria species, researchers have described more than 20 bites with the delayed onset of severe and diffuse muscle cramps, lasting for several days, that in most cases resolved completely with the use of benzodiazepines and magnesium. In all cases, seeking medical aid is advised. Because other proteins are included when a toxin is injected, some individuals may suffer severe symptoms due to an allergic reaction rather than to the venom. Such allergic effects can be life-threatening.[citation needed] Additionally, the large fangs of a tarantula can inflict painful puncture wounds, which can lead to secondary bacterial infections if not properly treated.

Before biting, a tarantula may signal its intention to attack by rearing up into a "threat posture", which may involve raising its prosoma and lifting its front legs into the air, spreading and extending its fangs, and (in certain species) making a loud hissing by stridulating. Tarantulas often hold this position for longer than the duration of the original threat. Their next step, without biting, may be to slap down on the intruder with their raised front legs. If that response fails to deter the attacker, the tarantulas of the Americas may next turn away and flick urticating hairs toward the pursuing predator. The next response may be to leave the scene entirely, but especially if no line of retreat is available, their final response may also be to whirl suddenly and bite. Some tarantulas are well known to give "dry bites", i.e., they may defensively bite some animal that intrudes on their space and threatens them, but they do not pump venom into the wound.

New-world tarantulas—those indigenous to the Americas—have bites that generally pose little threat to humans (other than causing localized pain). Most of them are equipped with urticating hairs on their abdomens, and almost always throw these barbed bristles as the first line of defense. These bristles irritate sensitive areas of the body and especially seem to target curious animals that may sniff these bristles into the mucous membranes of the nose. Some species have more effective urticating bristles than others. The goliath birdeater is known for its particularly irritating urticating bristles. They can penetrate the cornea, so eye protection should be worn when handling such tarantulas.[22]

Old World tarantulas have no urticating bristles and are more likely to attack when disturbed. They often have more potent, medically significant venom, and are faster and much more nervous and defensive than New World species.

Some dangerous spider species are related to tarantulas and are frequently confused with them. A popular urban legend maintains that deadly varieties of tarantula exist somewhere in South America. This claim is often made without identifying a particular spider, although the "banana tarantula" is sometimes named. A likely candidate for the true identity of this spider is the dangerous Brazilian wandering spider (Phoneutria fera) of the family Ctenidae, as it is sometimes found hiding in clusters of bananas and is one of several spiders called "banana spiders". It is not technically a tarantula, but it is fairly large (4- to 5-inch legspan), somewhat ″hairy″, and is highly venomous to humans. Another dangerous type of spiders that have been confused with tarantulas are the Australian funnel-web spiders. The best known species of these is the Sydney funnel-web spider (Atrax robustus) a spider that is aggressive, highly venomous, and (prior to the development of antivenom in the 1980s) was responsible for numerous deaths in Australia. These spiders are members of the same infraorder as tarantulas, Mygalomorphae. Some Australians use the slang term "triantelope" (a corruption of the incorrect term tarantula, which is also used) for large, ″hairy″, and harmless members of the huntsman spider family, which are often found on interior household walls and in automobiles.[23]

Sexual dimorphism

Some tarantula species exhibit pronounced sexual dimorphism. Males tend to be smaller (especially their abdomens, which can appear quite narrow) and may be dull in color when compared to their female counterparts, as in the species Haplopelma lividum. Mature male tarantulas also may have tibial hooks on their front legs, which are used to restrain the female's fangs during copulation. Males typically have longer legs than the females.

Male California ebony tarantula (Aphonopelma eutylenum) wandering near Exeter, CA

A juvenile male's sex can be determined by looking at a cast exuvia for epiandrous fusillae or spermathecae. Females possess spermathecae, except for the species Sickius longibulbi and Encyocratella olivacea.[24][25] Males have much shorter lifespans than females because they die relatively soon after maturing. Few live long enough for a postultimate molt, which is unlikely in natural habitats because they are vulnerable to predation, but has happened in captivity, though rarely. Most males do not live through this molt, as they tend to get their emboli, mature male sexual organs on pedipalps, stuck in the molt. Most tarantula fanciers regard females as more desirable as pets due to their much longer lifespans. Wild-caught tarantulas are often mature males because they wander out in the open and are more likely to be caught.

Life cycle

The molting process

Like other spiders, tarantulas have to shed their exoskeleton periodically as they grow, a process called molting. A young tarantula may do this several times a year as a part of the maturation process, while full-grown specimens only molt once a year or less, or sooner, to replace lost limbs or lost urticating hairs. It is visibly apparent that molting is imminent when the exoskeleton takes on a darker shade. If a tarantula previously used its urticating hairs, the bald patch turns from a peach color to deep blue. The tarantula also stops feeding and becomes more lethargic during this time.

While most Tarantulas species take between two and five years to reach sexual maturity, some species can take up to 10 years. Upon reaching adulthood, males typically have an 18-month period left to live so immediately go in search of a female mate. Although females continue to molt after reaching maturity, males rarely do again once they reach adulthood. Those that do often can become stuck during the molting process due to their sexual organs and die.

Females can live for 30 to 40 years.[26] Grammostola rosea spiders, which eat once or twice a week, have lived up to 20 years in captivity.[27] Some have survived on water alone for up to two years.[26]

Reproduction

The molted skin of a juvenile Phormictopus cancerides cancerides (second molting)

After reaching sexual maturity, a female tarantula normally mates and lays eggs once per year,[28][29] although they do not always do so.[30]

As with other spiders, the mechanics of intercourse are quite different from those of mammals. Once a male spider reaches maturity and becomes motivated to mate, he weaves a web mat on a flat surface. The spider then rubs his abdomen on the surface of this mat, and in so doing, releases a quantity of semen. He may then insert his pedipalps (short, leg-like appendages between the chelicerae and front legs) into the pool of semen. The pedipalps absorb the semen and keep it viable until a mate can be found. When a male spider detects the presence of a female, the two exchange signals to establish that they are of the same species. These signals may also lull the female into a receptive state. If the female is receptive, then the male approaches her and inserts his pedipalps into an opening in the lower surface of her abdomen, the opisthosoma. After the semen has been transferred to the receptive female's body, the male swiftly leaves the scene before the female recovers her appetite. Although females may show some aggression after mating, the male rarely becomes a meal.[citation needed][9]

Females deposit 50 to 2,000 eggs, depending on the species, in a silken egg sac and guard it for six to eight weeks. During this time, the females stay very close to the egg sacs and become more aggressive. Within most species, the females turn the egg sac often, which is called brooding. This keeps the eggs from deforming due to sitting in one position too long. The young spiderlings remain in the nest for some time after hatching, where they live off the remains of their yolk sacs before dispersing.[citation needed][31]

Taxonomy

Linnaeus placed all spiders in a single genus, Aranea. In 1802, Charles Athanase Walckenaer separated mygalomorph spiders into a separate genus, Mygale, leaving all other spiders in Aranea. However, Mygale had already been used in 1800 by Georges Cuvier for a genus of mammals (in Greek, mygale means "shrew"). Accordingly, in 1869, Tamerlan Thorell used the family name "Theraphosoidae" (modern Theraphosidae) for the mygalomorph spiders known to him, rather than "Mygalidae" (as used, for example, by John Blackwall). Thorell later split the family into a number of genera, including Theraphosa.[32][33]

Subfamilies

A 2019 phylogenomic study recognized 12 subfamilies, one (Ischnocolinae) known not to be monophyletic.[34]

The relationship between the subfamilies found in the study is shown in the following cladogram.[34] The dual placing of Ischnocolinae is highlighted.

Theraphosidae

All the species that possess urticating hairs and have been seen to use them in bombardment behavior are placed in the "bombardier clade", although not all species in the included subfamilies possess such hairs (all Schismatothelinae lack them as do most Psalmopoeinae genera). It is not clear whether the possession of urticating hairs was an ancestral trait of the clade, and has been lost in some species, or whether it represents multiple gains. Foley et al. suggested that the second hypothesis appeared to be better supported.[34]

Other subfamilies that have been recognized include:[citation needed]

Genera

As of December 2023, the World Spider Catalog accepted the following genera:[1]

Former genera:

Fossil record

Fossils of mygalomorph spiders date back to the Triassic.[citation needed] One species assigned to the Theraphosidae is Protertheraphosa spinipes, found in Burmese amber, which is dated to the mid and late Cretaceous.[35]

See also

References

  1. ^ a b "Family: Theraphosidae Thorell, 1869". World Spider Catalog. Natural History Museum Bern. Retrieved 2 May 2022.
  2. ^ Shultz, Stanley; Shultz, Marguerite (2009). The Tarantula Keeper's Guide. Hauppauge, New York: Barron's. p. 28. ISBN 978-0-7641-3885-0.
  3. ^ "Currently valid spider genera and species", World Spider Catalog, Natural History Museum Bern, retrieved 20 August 2022
  4. ^ a b Blaikie, Andrew J; John Ellis; Roshini Sanders; Caroline J. MacEwen (24 May 1997). "Eye disease associated with handling pet tarantulas: three case reports". BMJ. 314 (7093): 1524–5. doi:10.1136/bmj.314.7093.1524. PMC 2126783. PMID 9183200.
  5. ^ Pomeroy, R. (2014, February 4). Pub. Real Clear Science, "Spiders, and Their Amazing Hydraulic Legs and Genitalia". Retrieved October 13, 2019, from https://www.realclearscience.com/blog/2013/02/spiders-their-amazing-hydraulic-legs-and-genitals.html.
  6. ^ Jovan, Dennis, Kj, & Kenneth. (2019, May 1). Theraphosa blondi. Retrieved October 13, 2019, from https://www.theraphosidae.be/en/theraphosa-blondi/ Archived 18 May 2021 at the Wayback Machine.
  7. ^ a b Lewis, Tanya (17 October 2014). "Goliath Encounter: Puppy-Sized Spider Surprises Scientist in Rainforest". LiveScience.com. Live Science. Archived from the original on 4 December 2014. Retrieved 29 November 2014.
  8. ^ a b "Tarantula vs Other Spiders – 7 Key Differences – Fauna Facts". Retrieved 15 July 2022.
  9. ^ a b Fabre, Jean-Henri; Translated by Alexander Teixeira de Mattos (1916) The Life of the spider, Dodd, Mead, New York.
  10. ^ "Taranto". lifeinitaly. Archived from the original on 4 September 2015. Retrieved 29 August 2015.
  11. ^ a b c d e Estrada-Alvarez, Julio C. & Cameron, H.D. (2012). "Etymological origins of the generic names of Mexican tarantulas (Araneae:Theraphosidae)". Revista Ibérica de Aracnología (21): 153–160. Retrieved 10 October 2019.
  12. ^ Koch, C.L. (1850). Übersicht des Arachnidensystems, Heft 5 (in German). Nürnberg: J.L. Lotzbeck. p. 73. doi:10.5962/bhl.title.39561.
  13. ^ Foelix, Rainer F. (1992). Biologie der Spinnen (in German). Stuttgart: Georg Thieme. p. 17. ISBN 3-13-575802-8.
  14. ^ Schmerler, Johann Adam (1794). Lateinisch-deutsches und deutsch lateinisches Wörterbuch 3. Aufl, Volume 2 (in German and Latin). Erlangen: J.J. Palm. p. 2402. OCLC 669374426. Retrieved 10 October 2019.
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  16. ^ Kovařík, F (2001), Chov sklípkanů (Keeping Tarantulas); Madagaskar, Jihlava, p. 23
  17. ^ Piper, R (2007) Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals, Greenwood Press, ISBN 0313339228.
  18. ^ "Wild or Giant Centipedes versus Other Predators". howtogetridofhousecentipedes. Archived from the original on 4 March 2016. Retrieved 29 August 2015.
  19. ^ Murton, Willow. "Tarantula kebab anyone?". BBC Food Blog, with video from Human Planet. BBC. Archived from the original on 6 December 2011. Retrieved 7 December 2011.
  20. ^ Cooke, J.A.L.; Roth, V.D.; Miller, F.H. (1972). "The urticating hairs of theraphosid spiders". American Museum Novitates: 2498. hdl:2246/2705.
  21. ^ Klátil, Lubomír (1998). Sklípkani: krasavci s chlupatýma nohama. Nakl. Kabourek Zlín. p. 40. ISBN 978-80-901466-5-5. Archived from the original on 31 December 2013.
  22. ^ Tarantula shoots sharp bristles into owner's eye[dead link] NBC News/LiveScience
  23. ^ Huntsman Spiders Archived 12 July 2009 at the Wayback Machine at The Australian Wonder Book of Knowledge
  24. ^ Bertani, R.; Fukushima, C.S.; Júnior, P.I.S. (2008). "Mating behavior of Sickius longibulbi (Araneae, Theraphosidae, Ischnocolinae), a spider that lacks spermathecae" (PDF). The Journal of Arachnology. 36 (2): 331–335. doi:10.1636/CSt07-100.1. S2CID 55978068.
  25. ^ Gallon, R. C. (2003). "A new African arboreal genus and species of theraphosid spider (Araneae, Theraphosidae, Stromatopelminae) which lacks spermathecae" (PDF). Bulletin of the British Arachnological Society. 12 (9): 405–411.
  26. ^ a b Schultz, Stanley A.; Schultz, Marguerite J. (1998). The Tarantula Keeper's Guide. Barron's Educational Series. p. 75. ISBN 0764100769.
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  28. ^ Ferretti, Nelson; Pérez-Miles, Fernando; González, Alda (13 May 2014). "Historical relationships among Argentinean biogeographic provinces based on mygalomorph spider distribution data (Araneae: Mygalomorphae)". Studies on Neotropical Fauna and Environment. 49 (1): 2. Bibcode:2014SNFE...49....1F. doi:10.1080/01650521.2014.903616. hdl:11336/33878. S2CID 85259715. Mygalomorph spiders are well-suited models for biogeographical analysis... They are long-lived and univoltine, and show high local endemicity.
  29. ^ Punzo, Fred (2007). Spiders: Biology, Ecology, Natural History, and Behaviour. Brill. p. 182. ISBN 9789004156647.
  30. ^ Punzo, Fred (1999). "Aspects of the natural history and behavioural ecology of the tarantula spider Aphonopelma hentzi (Girard, 1854) (Orthognatha, Theraphosidae)". Bulletin of the British Arachnological Society. 11 (4): 122.
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Further reading