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{{Short description|Species of lizard}}
{{italic title}}
{{Use dmy dates|date=June 2020}}
{{Use Australian English|date=October 2015}}
{{Use Australian English|date=October 2015}}
{{Speciesbox
{{Taxobox
⚫
| name = ''Ctenophorus pictus''
| image = Ctenophorus pictus.JPG
| image = Ctenophorus pictus.JPG
⚫
| image_caption = ''Ctenophorus pictus'', painted dragon
| image_width = 250px
| status = LC
⚫
| image_caption = ''Ctenophorus pictus'', painted dragon
| status_system = IUCN3.1
| regnum = [[Animal]]ia
| status_ref = <ref name="iucn status 20 November 2021">{{cite iucn |author=Melville, J. |author2=Sanderson, C. |author3=Shea, G. |author4=Cogger, H. |date=2017 |title=''Ctenophorus pictus'' |volume=2017 |page=e.T83488800A83488898 |doi=10.2305/IUCN.UK.2017-3.RLTS.T83488800A83488898.en |access-date=20 November 2021}}</ref>
| phylum = [[Chordata]]
⚫
| genus = Ctenophorus
| subphylum = [[Vertebrate|Vertebrata]]
⚫
| species = pictus
| classis = [[Reptilia]]
⚫
| authority = ([[Wilhelm Peters|W. Peters]], 1866)
| ordo = [[Squamata]]
| subordo = [[Lacertilia]]
| familia = [[Agamidae]]
| subfamilia = [[Amphibolurinae]]
| genus = ''[[Ctenophorus]]''
⚫
| species = '''''C. pictus'''''
| binomial = ''Ctenophorus pictus''
⚫
| binomial_authority = ([[Wilhelm Peters|W. Peters]], 1866)
| synonyms = *''Amphibolurus pictus'' <small>W. Peters, 1866</small>
| synonyms = *''Amphibolurus pictus'' <small>W. Peters, 1866</small>
*''Ctenophorus pictus'' <small>— [[Harold Cogger|Cogger]], 2000</small><ref>The Reptile Database. www.reptile-database.org.</ref>
*''Ctenophorus pictus'' <small>— [[Harold Cogger|Cogger]], 2000</small><ref>The Reptile Database. www.reptile-database.org.</ref>
}}
}}

'''''Ctenophorus pictus''''', commonly known as the '''painted dragon''',<ref name=Waite>Waite ER (Editor). (1929). ''The Reptiles and Amphibians of South Australia''. Adelaide: Government Printer. 270 pp.</ref> is a [[species]] of [[lizard]] from the [[Agamidae]] [[Family (biology)|family]]. ''Ctenophorus pictus'' is [[Endemism|endemic]] to the drier areas of southern and central [[Australia]].
'''''Ctenophorus pictus''''', commonly known as the '''painted ground-dragon'''<ref name="iucn status 20 November 2021" /> or '''painted dragon''',<ref name=Waite>Waite ER (Editor). (1929). ''The Reptiles and Amphibians of South Australia''. Adelaide: Government Printer. 270 pp.</ref> is a [[species]] of [[lizard]] from the [[family (biology)|family]] [[Agamidae]]. It is [[endemic]] to the drier areas of southern and central [[Australia]].


==Description==
==Description==
[[File:Ctenophorus pictus - dorsal.JPG|thumb|left|Painted dragon <br />dorsal view]]
[[File:Ctenophorus pictus - dorsal.JPG|thumb|left|Painted dragon <br />dorsal view]]
The painted dragon is a medium-sized terrestrial lizard with a short, deep head and uniform body scales. The appearance of this species is extremely variable as it can appear in a number of different colour combinations.<ref name=Wilson>Wilson S, Swan G. (2013). ''A Complete Guide to Reptiles of Australia'' (Fourth Edition). London: New Holland Publishers. 592 pp. ISBN 978-1921517280.</ref> Adult males can be brown, yellowish-brown, orange to reddish-brown with dark-edged pale bars, blotches or spots overlaying a dark vertebral stripe.<ref name=Wilson /> The flanks are spotted, variegated (irregular patches/streaks), or reticulated (net-like pattern) with dark brown and dotted with scattered, pale, dark-edged spots which will sometimes be aligned perpendicular to the vertebral stripe.<ref name=Cogger>[[Harold Cogger|Cogger HG]]. (2014). ''Reptiles & Amphibians of Australia''. Seventh Edition. Collingwood: CSIRO Publishing. 1,036 pp. ISBN 978-0643100350 (paperback).</ref> The limbs are variegated and the pattern on the tail is often obscure but broad dark bands at the base.<ref name=Cogger /> Breeding males will exhibit a bright blue flush over the lower lips, throat and limbs and a bright yellow to orange flush over the anterior chest and shoulders.<ref name=Wilson /> Adult females and juveniles are duller in colour, lacking the bright blue and yellow pigment<ref name=Wilson /> with females being commonly found in a rusty brown colour.<ref name=Waite />
The painted dragon is a medium-sized terrestrial lizard with a short, deep head and uniform body scales. The appearance of this species is extremely variable as it can appear in a number of different colour combinations.<ref name=Wilson>Wilson S, Swan G. (2013). ''A Complete Guide to Reptiles of Australia'' (Fourth Edition). London: New Holland Publishers. 592 pp. {{ISBN|978-1921517280}}.</ref> Adult males can be brown, yellowish brown, orange to reddish brown with dark-edged pale bars, blotches or spots overlaying a dark vertebral stripe.<ref name=Wilson /> The flanks are spotted, variegated (irregular patches/streaks), or reticulated (net-like pattern) with dark brown and dotted with scattered, pale, dark-edged spots which will sometimes be aligned perpendicular to the vertebral stripe.<ref name=Cogger>[[Harold Cogger|Cogger HG]]. (2014). ''Reptiles & Amphibians of Australia''. Seventh Edition. Collingwood: CSIRO Publishing. 1,036 pp. {{ISBN|978-0643100350}} (paperback).</ref> The limbs are variegated and the pattern on the tail is often obscure but broad dark bands at the base.<ref name=Cogger /> Breeding males will exhibit a bright blue flush over the lower lips, throat and limbs and a bright yellow to orange flush over the anterior chest and shoulders.<ref name=Wilson /> Adult females and juveniles are duller in colour, lacking the bright blue and yellow pigment<ref name=Wilson /> with females being commonly found in a rusty brown colour.<ref name=Waite />


The scales, though varying slightly in size in different parts, are relatively uniform across the body<ref name=Waite /> and are smooth to the touch.<ref name=Cogger /> A low crest on the back of the neck is often present which males will raise when alarmed<ref name=Hoser>Hoser RT. (1989). ''Australian Reptiles and Frogs''. Sydney: Pierson & Co.</ref> and usually a distinct vertebral series of slightly enlarged scales can be found along the back.<ref name=Cogger /> The ears are exposed on the side of its head and it has rather large and conspicuous eardrums.<ref name=Cogger />
The scales, though varying slightly in size in different parts, are relatively uniform across the body<ref name=Waite /> and are smooth to the touch.<ref name=Cogger /> A low crest on the back of the neck is often present which males will raise when alarmed<ref name=Hoser>Hoser RT. (1989). ''Australian Reptiles and Frogs''. Sydney: Pierson & Co.</ref> and usually a distinct vertebral series of slightly enlarged scales can be found along the back.<ref name=Cogger /> The ears are exposed on the side of its head and it has rather large and conspicuous eardrums.<ref name=Cogger />
Line 33: Line 26:


==Distribution and habitat==
==Distribution and habitat==
Painted dragons are found throughout the drier parts of south-eastern [[Western Australia]], across [[South Australia]] to north-western [[Victoria (Australia)|Victoria]] and central-western [[New South Wales]].<ref name=Cogger /> They prefer semi-arid to arid regions, favouring shrublands and hummock grasslands on sandy and saline soils.<ref name=Wilson />
Painted dragons are found throughout the drier parts of southeastern [[Western Australia]], across [[South Australia]] to northwestern [[Victoria (Australia)|Victoria]]<ref name="SLFVM">Swan, M., Watharow, S. (2005) ''Snakes, Lizards and Frogs of the Victorian Mallee'', CSIRO Publishing, Collingwood, Victoria, Australia {{ISBN|0643091343}}</ref> and central-western [[New South Wales]].<ref name=Cogger /> They prefer semi-arid to arid regions, favouring shrublands and hummock grasslands on sandy and saline soils.<ref name=Wilson />


==Ecology==
==Ecology==
Like most [[Agamidae|agamids]], painted dragons are swift-moving reptiles, capable of impressive sprints over short distances.<ref name=Steve>Wilson SK. (2012). ''Australian Lizards: A Natural History''. Collingwood: CSIRO Publishing. 208 pp. ISBN 978-0643106406.</ref> This [[Diurnality|diurnal]] (day-active) lizard, like the majority reptiles, is an [[ectotherm]] meaning that it has to rely on its environment to regulate body temperature and as a result will spend considerable time basking to absorb heat.<ref name=Mayhew>{{cite journal|author=Mayhew WW|year=1963|title=Observations on Captive ''Amphibolurus pictus'' an Australian Agamid Lizard|journal=Herpetologica|volume=19|issue=2|pages=81–88|jstor=3890542}}</ref> Known to be especially fond of low vegetation and ground debris such as fallen logs and branches,<ref name=Cogger /> it occupies short burrows often concealed at the base of shrubs such as [[Atriplex|saltbush]].<ref name=Wilson /><ref name=Hoser /> Unlike the majority of other [[Agamidae|agamids]] which like to perch in elevated places,<ref name=Steve /> this species prefers to rest on low branches,<ref name=Wilson /> from which it will forage over the surrounding open areas and ground litter.<ref name=Wilson /><ref name=Cogger /><ref name=Hoser /> When disturbed or alarmed it will quickly retreat to the safety of the nearby burrow.<ref name=Hoser />
Like most [[Agamidae|agamids]], painted dragons are swift-moving reptiles, capable of impressive sprints over short distances.<ref name=Steve>Wilson SK. (2012). ''Australian Lizards: A Natural History''. Collingwood: CSIRO Publishing. 208 pp. {{ISBN|978-0643106406}}.</ref> This [[Diurnality|diurnal]] (day-active) lizard, like the majority reptiles, is an [[ectotherm]] meaning that it has to rely on its environment to regulate body temperature and as a result will spend considerable time basking to absorb heat.<ref name=Mayhew>{{cite journal|author=Mayhew WW|year=1963|title=Observations on Captive ''Amphibolurus pictus'' an Australian Agamid Lizard|journal=Herpetologica|volume=19|issue=2|pages=81–88|jstor=3890542}}</ref> Known to be especially fond of low vegetation and ground debris such as fallen logs and branches,<ref name=Cogger /> it occupies short burrows often concealed at the base of shrubs such as [[Atriplex|saltbush]].<ref name=Wilson /><ref name=Hoser /> Unlike the majority of other [[Agamidae|agamids]] which like to perch in elevated places,<ref name=Steve /> this species prefers to rest on low branches,<ref name=Wilson /> from which it will forage over the surrounding open areas and ground litter.<ref name=Wilson /><ref name=Cogger /><ref name=Hoser /> When disturbed or alarmed it will quickly retreat to the safety of the nearby burrow.<ref name=Hoser />


Painted dragons possess many of the traits common to the [[Agamidae]] family. They are very alert lizards with an upright stance and acute vision which they will use to search for prey and keep an eye out for mates, rivals, and predators.<ref name=Steve /> Most of their communication is visually oriented with stylised head bops and dips, arm waving, and tail lashing playing a big part.<ref name=Steve /> When looking for food, [[Agamidae|agamids]] will seize their prey with the use of a short, thick tongue rather than their jaws.<ref name=Steve />
Painted dragons possess many of the traits common to the family [[Agamidae]]. They are very alert lizards with an upright stance and acute vision which they will use to search for prey and keep an eye out for mates, rivals, and predators.<ref name=Steve /> Most of their communication is visually oriented with stylised head bops and dips, arm waving, and tail lashing playing a big part.<ref name=Steve /> When looking for food, [[Agamidae|agamids]] will seize their prey with the use of a short, thick tongue rather than their jaws.<ref name=Steve />


==Diet==
==Diet==
Employing a sit-and-wait hunting technique, painted dragons will use their keen vision to detect most of their prey by the telltale movement they make.<ref name=Steve /> Accordingly, their diets consist largely of surface-active, mobile prey resulting in them consuming a range of [[arthropods]]. A strange feature of the [[Agamidae]] family is that ants, which are often avoided by other lizards, feature prominently in the diets of many of its species.<ref name=Steve /> While it is believed that this is more of a reflection on availability than preference, it still remains to be explained why they take ants at all when so many other lizards actively avoid them due to the [[formic acid]] they contain.<ref name=Steve /> It is presumed that they have developed some sort of mechanism to deal with the ingestion of this chemical.<ref name=Steve />
Employing a sit-and-wait hunting technique, painted dragons will use their keen vision to detect most of their prey by the telltale movement they make.<ref name=Steve /> Accordingly, their diets consist largely of surface-active, mobile prey resulting in them consuming a range of [[arthropods]]. A strange feature of the family [[Agamidae]] is that ants, which are often avoided by other lizards, feature prominently in the diets of many of its species.<ref name=Steve /> While it is believed that this is more of a reflection on availability than preference, it still remains to be explained why they take ants at all when so many other lizards actively avoid them due to the [[formic acid]] they contain.<ref name=Steve /> It is presumed that they have developed some sort of mechanism to deal with the ingestion of this chemical.<ref name=Steve />


While this species is known to be predominately [[Insectivore|insectivorous]],<ref name=Hoser /> specimens kept in captivity have been observed supplementing their diet with considerable amounts of plant matter.<ref name=Mayhew />
While this species is known to be predominantly [[Insectivore|insectivorous]],<ref name=Hoser /> specimens kept in captivity have been observed supplementing their diet with considerable amounts of plant matter.<ref name=Mayhew />


==Colour polymorphism==
==Colour polymorphism==
Coloration in male painted dragon populations, ''Ctenophorus pictus'', is extremely variable, ranging from reddish-brown to orange to yellowish-brown, with orange being the least common. In studies of colour polymorphism, individual lizards have been categorised by their predominant colour into three discrete groups, red, orange and yellow.<ref name="ReferenceA">{{cite journal|last1=McLean|first1=Claire A.|last2=Stuart-Fox|first2=Devi|last3=Moussalli|first3=Adnan|title=Environment, but not genetic divergence, influences geographic variation in colour morph frequencies in a lizard|journal=BMC Evolutionary Biology|date=8 August 2015|volume=15|issue=1|doi=10.1186/s12862-015-0442-x}}</ref>The differences in male coloration have also been found to be related to lizard behavior, in both males and females.
Colouration in male painted dragon populations is extremely variable, ranging from reddish brown to orange to yellowish brown, with orange being the least common. In studies of [[Polymorphism (biology)|colour polymorphism]], individual lizards have been categorised by their predominant colour into three discrete groups: red, orange and yellow<ref>.{{cite journal|last1=McLean|first1=Claire A.|last2=Stuart-Fox|first2=Devi|last3=Moussalli|first3=Adnan|title=Environment, but not genetic divergence, influences geographic variation in colour morph frequencies in a lizard|journal=BMC Evolutionary Biology|date=8 August 2015|volume=15|issue=1|page=156 |doi=10.1186/s12862-015-0442-x|pmid=26253642|pmc=4528382 |doi-access=free }}</ref>


The variable appearance of the males has been correlated to higher sexual selection as it has been found that, between yellow and red coloured male lizards, female lizards prefer red coloured ones.<ref>{{cite journal|last1=Healey|first1=Mo|last2=Uller|first2=Tobias|last3=Olsson|first3=Mats|title=Seeing red: morph-specific contest success and survival rates in a colour-polymorphic agamid lizard|journal=Animal Behaviour|date=August 2007|volume=74|issue=2|pages=337–341|doi=10.1016/j.anbehav.2006.09.017}}</ref> The females chose males that are naturally red, based on genes, as well as lizards that just appeared red due to the environment, equally. The red coloration may indicate indirect benefits to the females, showing that the male has good genes.
Higher [[sexual selection]] is correlated with the variable appearance of males. Between yellow and red coloured male lizards, female lizards sexually select for red-coloured males.<ref name="ReferenceA">{{cite journal|last1=Healey|first1=Mo|last2=Uller|first2=Tobias|last3=Olsson|first3=Mats|title=Seeing red: morph-specific contest success and survival rates in a colour-polymorphic agamid lizard|journal=Animal Behaviour|date=August 2007|volume=74|issue=2|pages=337–341|doi=10.1016/j.anbehav.2006.09.017}}</ref> The red colouration may indicate indirect benefits to the females, showing that the male has beneficial genes. These include having high testosterone levels, which in turn affects the ability to fight off predators and an aptitude to defend his territory and offspring.<ref name="ReferenceA"/>


In addition to preference of the red variants by females, red males also have higher testosterone levels than their yellow male counterparts. The red male lizards also experience a more rapid increase in testosterone levels.<ref>{{cite journal|last1=Olsson|first1=Mats|last2=Healey|first2=Mo|last3=Astheimer|first3=Lee|title=Afternoon T: Testosterone level is higher in red than yellow male polychromatic lizards|journal=Physiology & Behavior|date=August 2007|volume=91|issue=5|pages=531–534|doi=10.1016/j.physbeh.2007.04.025}}</ref> In mating situations, red lizards may out-compete yellow lizards, because they will be ready to mate faster. Testosterone is also linked to aggression; increased aggression seen from a rapid increase in testosterone levels in red lizards also gives them a fighting advantage over predators and other lizards.
Red males have higher testosterone levels than their yellow male counterparts.<ref name="Afternoon T 2007">{{cite journal|last1=Olsson|first1=Mats|last2=Healey|first2=Mo|last3=Astheimer|first3=Lee|title=Afternoon T: Testosterone level is higher in red than yellow male polychromatic lizards|journal=Physiology & Behavior|date=August 2007|volume=91|issue=5|pages=531–534|doi=10.1016/j.physbeh.2007.04.025|pmid=17521685}}</ref> Testosterone is linked to aggression; increased aggression seen from a rapid increase in testosterone levels in red lizards gives them a fighting advantage in physical competition with predators.<ref name="Afternoon T 2007"/> They also show more aggressive strategies in out-competing their yellow counterparts for more mating opportunities.<ref name="ReferenceA"/> In addition, red males defend their territory more fiercely and begin this behaviour earlier in the year, gaining a behavioural dominance over yellow males.<ref name="ReferenceB">{{cite journal|last1=Olsson|first1=Mats|last2=Schwartz|first2=Tonia|last3=Uller|first3=Tobias|last4=Healey|first4=Mo|title=Effects of sperm storage and male colour on probability of paternity in a polychromatic lizard|journal=Animal Behaviour|date=February 2009|volume=77|issue=2|pages=419–424|doi=10.1016/j.anbehav.2008.10.017}}</ref> However, the increased aggression and early defence of territory that red lizards express has a significant metabolic expense, which decreases overall fitness.<ref>{{cite journal|last1=OLSSON|first1=MATS|last2=HEALEY|first2=MO|last3=WAPSTRA|first3=ERIK|last4=SCHWARTZ|first4=TONIA|last5=LEBAS|first5=NATASHA|last6=ULLER|first6=TOBIAS|title=Mating system variation and morph fluctuations in a polymorphic lizard|journal=Molecular Ecology|date=December 2007|volume=16|issue=24|pages=5307–5315|doi=10.1111/j.1365-294X.2007.03578.x|pmid=18092994}}</ref>


On the other hand, yellow males show high survival rates, potentially due to relatively lower energy costs in territorial defence. Furthermore, yellow males show higher sperm counts than the red lizards.<ref name="ReferenceB"/> Yellow males generally have larger-sized testes than red males, and they copulate for shorter periods of time. When the yellow males mate, they have, on average, three times as many offspring as their red counterparts.<ref name="ReferenceB"/> This dually high survivability among both red and yellow males may be why both colour morphs are maintained in painted dragon populations.
Red males show more aggressive strategies in out-competing the yellow males and getting more mating opportunities. The red males defend their territory more fiercely and begin this behaviour earlier in the year,<ref>{{cite journal|last1=Olsson|first1=Mats|last2=Schwartz|first2=Tonia|last3=Uller|first3=Tobias|last4=Healey|first4=Mo|title=Effects of sperm storage and male colour on probability of paternity in a polychromatic lizard|journal=Animal Behaviour|date=February 2009|volume=77|issue=2|pages=419–424|doi=10.1016/j.anbehav.2008.10.017}}</ref> gaining a behavioural dominance over yellow males.


While sexual selection generally favours red males, [[natural selection]] maintains variation by selecting for more energetically efficient yellow males.<ref>{{cite journal|last1=McLean|first1=Claire A.|last2=Stuart-Fox|first2=Devi|last3=Moussalli|first3=Adnan|title=Environment, but not genetic divergence, influences geographic variation in colour morph frequencies in a lizard|journal=BMC Evolutionary Biology|date=8 August 2015|volume=15|issue=1|page=156 |doi=10.1186/s12862-015-0442-x|pmid=26253642|pmc=4528382 |doi-access=free }}</ref> Both colour traits have an evolutionary advantage, which explains the maintenance of this polymorphism in nature.
This increased aggression, in addition to early defending of territory, takes a metabolic toll on the red lizards. This energy cost decreases the fitness of the red males overall. Thus, even though females may show a higher preference for red males, yellow males also have high survival rates, since they do not use as much energy in territorial defence. This may be one of the explanations for why both colour morphs are maintained in the population.


===Breeding colouration and oxidative stress===
Yellow males have been found to have higher sperm levels than red males.<ref name="ReferenceB">{{cite journal|last1=Olsson|first1=Mats|last2=Schwartz|first2=Tonia|last3=Uller|first3=Tobias|last4=Healey|first4=Mo|title=Effects of sperm storage and male colour on probability of paternity in a polychromatic lizard|journal=Animal Behaviour|date=February 2009|volume=77|issue=2|pages=419–424|doi=10.1016/j.anbehav.2008.10.017}}</ref> The size of the yellow males’ testes is also three times the size of the red males, and they copulate for shorter periods of time. This is one way that the yellow morph displays a selection advantage, and how this variant is maintained in the populations.


The breeding colouration of male ''C. pictus'' is brightly conspicuous, but declines with [[ageing|aging]]. Experiments involving administration of [[antioxidant]]s to ''C. pictus'' males led to the conclusion that breeding colouration is a reflection of innate anti-oxidation capacity that protects against [[oxidative stress|oxidative damage]], including oxidative [[DNA oxidation|DNA damage]].<ref name="pmid22834746">{{cite journal |vauthors=Olsson M, Tobler M, Healey M, Perrin C, Wilson M |title=A significant component of ageing (DNA damage) is reflected in fading breeding colours: an experimental test using innate antioxidant mimetics in painted dragon lizards |journal=Evolution |volume=66 |issue=8 |pages=2475–83 |date=August 2012 |pmid=22834746 |doi=10.1111/j.1558-5646.2012.01617.x |doi-access=free }}</ref> Thus male breeding colouration likely acts as an indicator to females of the underlying level of [[oxidative stress]] induced damage in potential mates.
Although it seems that red lizards are the superior variant in terms of sexual selection, all the polymorphs still exist in nature. The reason for this is that variation in polymorphic lizards is maintained in different environments. The variation is often found between, rather than within, populations. Some environments are better suited for the survival of yellow variants; in others, red variants have higher fitness. Females have largely been shown to prefer red males. However, yellow males have high survival rates since they use energy for sustenance and survival, rather than impressing females. This shows that natural selection has a large role in maintaining variation, even more so than gene flow.<ref name="ReferenceA"/>


==References==
==References==
{{reflist}}
{{Reflist}}


==Further reading==
==Further reading==
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*[[Wilhelm Peters|Peters W]]. (1866). "''Mittheilung über neue Amphibien'' (Amphibolurus, Lygosoma, Cyclodus, Masticophis, Crotaphopeltis) ''und Fische'' (Diagramma, Hapalogenys) ''des Kgl. Zoologischens Museums''". ''Monatsberichte der Königlich Preussischen Akademie der Wissenschaften zu Berlin'' '''1866''': 86–96. (''Amphibolurus pictus'', new species, pp.&nbsp;88–89). (in [[German language|German]]).
*[[Wilhelm Peters|Peters W]]. (1866). "''Mittheilung über neue Amphibien'' (Amphibolurus, Lygosoma, Cyclodus, Masticophis, Crotaphopeltis) ''und Fische'' (Diagramma, Hapalogenys) ''des Kgl. Zoologischens Museums''". ''Monatsberichte der Königlich Preussischen Akademie der Wissenschaften zu Berlin'' '''1866''': 86–96. (''Amphibolurus pictus'', new species, pp.&nbsp;88–89). (in [[German language|German]]).


{{Taxonbar|from=Q3006476}}
⚫
[[Category:Agamidae]]

⚫
[[Category:Reptiles of Australia]]
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[[Category:Ctenophorus|pictus]]
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[[Category:Agamid lizards of Australia]]
[[Category:Reptiles described in 1866]]
[[Category:Taxa named by Wilhelm Peters]]

Latest revision as of 13:47, 3 December 2023

Ctenophorus pictus
Ctenophorus pictus, painted dragon
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Iguania
Family: Agamidae
Genus: Ctenophorus
Species:
C. pictus
Binomial name
Ctenophorus pictus
(W. Peters, 1866)
Synonyms
  • Amphibolurus pictus W. Peters, 1866
  • Ctenophorus pictus — Cogger, 2000[2]

Ctenophorus pictus, commonly known as the painted ground-dragon[1] or painted dragon,[3] is a species of lizard from the family Agamidae. It is endemic to the drier areas of southern and central Australia.

Description

[edit]
Painted dragon
dorsal view

The painted dragon is a medium-sized terrestrial lizard with a short, deep head and uniform body scales. The appearance of this species is extremely variable as it can appear in a number of different colour combinations.[4] Adult males can be brown, yellowish brown, orange to reddish brown with dark-edged pale bars, blotches or spots overlaying a dark vertebral stripe.[4] The flanks are spotted, variegated (irregular patches/streaks), or reticulated (net-like pattern) with dark brown and dotted with scattered, pale, dark-edged spots which will sometimes be aligned perpendicular to the vertebral stripe.[5] The limbs are variegated and the pattern on the tail is often obscure but broad dark bands at the base.[5] Breeding males will exhibit a bright blue flush over the lower lips, throat and limbs and a bright yellow to orange flush over the anterior chest and shoulders.[4] Adult females and juveniles are duller in colour, lacking the bright blue and yellow pigment[4] with females being commonly found in a rusty brown colour.[3]

The scales, though varying slightly in size in different parts, are relatively uniform across the body[3] and are smooth to the touch.[5] A low crest on the back of the neck is often present which males will raise when alarmed[6] and usually a distinct vertebral series of slightly enlarged scales can be found along the back.[5] The ears are exposed on the side of its head and it has rather large and conspicuous eardrums.[5]

Adults will grow to a full length of around 18–25 cm (7.1–9.8 in), with a snout-to-vent length of about 7.5 cm (3.0 in).[4][6] The tail of this species usually accounts for about 65% of its total body length.[5]

Distribution and habitat

[edit]

Painted dragons are found throughout the drier parts of southeastern Western Australia, across South Australia to northwestern Victoria[7] and central-western New South Wales.[5] They prefer semi-arid to arid regions, favouring shrublands and hummock grasslands on sandy and saline soils.[4]

Ecology

[edit]

Like most agamids, painted dragons are swift-moving reptiles, capable of impressive sprints over short distances.[8] This diurnal (day-active) lizard, like the majority reptiles, is an ectotherm meaning that it has to rely on its environment to regulate body temperature and as a result will spend considerable time basking to absorb heat.[9] Known to be especially fond of low vegetation and ground debris such as fallen logs and branches,[5] it occupies short burrows often concealed at the base of shrubs such as saltbush.[4][6] Unlike the majority of other agamids which like to perch in elevated places,[8] this species prefers to rest on low branches,[4] from which it will forage over the surrounding open areas and ground litter.[4][5][6] When disturbed or alarmed it will quickly retreat to the safety of the nearby burrow.[6]

Painted dragons possess many of the traits common to the family Agamidae. They are very alert lizards with an upright stance and acute vision which they will use to search for prey and keep an eye out for mates, rivals, and predators.[8] Most of their communication is visually oriented with stylised head bops and dips, arm waving, and tail lashing playing a big part.[8] When looking for food, agamids will seize their prey with the use of a short, thick tongue rather than their jaws.[8]

Diet

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Employing a sit-and-wait hunting technique, painted dragons will use their keen vision to detect most of their prey by the telltale movement they make.[8] Accordingly, their diets consist largely of surface-active, mobile prey resulting in them consuming a range of arthropods. A strange feature of the family Agamidae is that ants, which are often avoided by other lizards, feature prominently in the diets of many of its species.[8] While it is believed that this is more of a reflection on availability than preference, it still remains to be explained why they take ants at all when so many other lizards actively avoid them due to the formic acid they contain.[8] It is presumed that they have developed some sort of mechanism to deal with the ingestion of this chemical.[8]

While this species is known to be predominantly insectivorous,[6] specimens kept in captivity have been observed supplementing their diet with considerable amounts of plant matter.[9]

Colour polymorphism

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Colouration in male painted dragon populations is extremely variable, ranging from reddish brown to orange to yellowish brown, with orange being the least common. In studies of colour polymorphism, individual lizards have been categorised by their predominant colour into three discrete groups: red, orange and yellow[10]

Higher sexual selection is correlated with the variable appearance of males. Between yellow and red coloured male lizards, female lizards sexually select for red-coloured males.[11] The red colouration may indicate indirect benefits to the females, showing that the male has beneficial genes. These include having high testosterone levels, which in turn affects the ability to fight off predators and an aptitude to defend his territory and offspring.[11]

Red males have higher testosterone levels than their yellow male counterparts.[12] Testosterone is linked to aggression; increased aggression seen from a rapid increase in testosterone levels in red lizards gives them a fighting advantage in physical competition with predators.[12] They also show more aggressive strategies in out-competing their yellow counterparts for more mating opportunities.[11] In addition, red males defend their territory more fiercely and begin this behaviour earlier in the year, gaining a behavioural dominance over yellow males.[13] However, the increased aggression and early defence of territory that red lizards express has a significant metabolic expense, which decreases overall fitness.[14]

On the other hand, yellow males show high survival rates, potentially due to relatively lower energy costs in territorial defence. Furthermore, yellow males show higher sperm counts than the red lizards.[13] Yellow males generally have larger-sized testes than red males, and they copulate for shorter periods of time. When the yellow males mate, they have, on average, three times as many offspring as their red counterparts.[13] This dually high survivability among both red and yellow males may be why both colour morphs are maintained in painted dragon populations.

While sexual selection generally favours red males, natural selection maintains variation by selecting for more energetically efficient yellow males.[15] Both colour traits have an evolutionary advantage, which explains the maintenance of this polymorphism in nature.

Breeding colouration and oxidative stress

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The breeding colouration of male C. pictus is brightly conspicuous, but declines with aging. Experiments involving administration of antioxidants to C. pictus males led to the conclusion that breeding colouration is a reflection of innate anti-oxidation capacity that protects against oxidative damage, including oxidative DNA damage.[16] Thus male breeding colouration likely acts as an indicator to females of the underlying level of oxidative stress induced damage in potential mates.

References

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  1. ^ a b Melville, J.; Sanderson, C.; Shea, G.; Cogger, H. (2017). "Ctenophorus pictus". IUCN Red List of Threatened Species. 2017: e.T83488800A83488898. doi:10.2305/IUCN.UK.2017-3.RLTS.T83488800A83488898.en. Retrieved 20 November 2021.
  2. ^ The Reptile Database. www.reptile-database.org.
  3. ^ a b c Waite ER (Editor). (1929). The Reptiles and Amphibians of South Australia. Adelaide: Government Printer. 270 pp.
  4. ^ a b c d e f g h i Wilson S, Swan G. (2013). A Complete Guide to Reptiles of Australia (Fourth Edition). London: New Holland Publishers. 592 pp. ISBN 978-1921517280.
  5. ^ a b c d e f g h i Cogger HG. (2014). Reptiles & Amphibians of Australia. Seventh Edition. Collingwood: CSIRO Publishing. 1,036 pp. ISBN 978-0643100350 (paperback).
  6. ^ a b c d e f Hoser RT. (1989). Australian Reptiles and Frogs. Sydney: Pierson & Co.
  7. ^ Swan, M., Watharow, S. (2005) Snakes, Lizards and Frogs of the Victorian Mallee, CSIRO Publishing, Collingwood, Victoria, Australia ISBN 0643091343
  8. ^ a b c d e f g h i Wilson SK. (2012). Australian Lizards: A Natural History. Collingwood: CSIRO Publishing. 208 pp. ISBN 978-0643106406.
  9. ^ a b Mayhew WW (1963). "Observations on Captive Amphibolurus pictus an Australian Agamid Lizard". Herpetologica. 19 (2): 81–88. JSTOR 3890542.
  10. ^ .McLean, Claire A.; Stuart-Fox, Devi; Moussalli, Adnan (8 August 2015). "Environment, but not genetic divergence, influences geographic variation in colour morph frequencies in a lizard". BMC Evolutionary Biology. 15 (1): 156. doi:10.1186/s12862-015-0442-x. PMC 4528382. PMID 26253642.
  11. ^ a b c Healey, Mo; Uller, Tobias; Olsson, Mats (August 2007). "Seeing red: morph-specific contest success and survival rates in a colour-polymorphic agamid lizard". Animal Behaviour. 74 (2): 337–341. doi:10.1016/j.anbehav.2006.09.017.
  12. ^ a b Olsson, Mats; Healey, Mo; Astheimer, Lee (August 2007). "Afternoon T: Testosterone level is higher in red than yellow male polychromatic lizards". Physiology & Behavior. 91 (5): 531–534. doi:10.1016/j.physbeh.2007.04.025. PMID 17521685.
  13. ^ a b c Olsson, Mats; Schwartz, Tonia; Uller, Tobias; Healey, Mo (February 2009). "Effects of sperm storage and male colour on probability of paternity in a polychromatic lizard". Animal Behaviour. 77 (2): 419–424. doi:10.1016/j.anbehav.2008.10.017.
  14. ^ OLSSON, MATS; HEALEY, MO; WAPSTRA, ERIK; SCHWARTZ, TONIA; LEBAS, NATASHA; ULLER, TOBIAS (December 2007). "Mating system variation and morph fluctuations in a polymorphic lizard". Molecular Ecology. 16 (24): 5307–5315. doi:10.1111/j.1365-294X.2007.03578.x. PMID 18092994.
  15. ^ McLean, Claire A.; Stuart-Fox, Devi; Moussalli, Adnan (8 August 2015). "Environment, but not genetic divergence, influences geographic variation in colour morph frequencies in a lizard". BMC Evolutionary Biology. 15 (1): 156. doi:10.1186/s12862-015-0442-x. PMC 4528382. PMID 26253642.
  16. ^ Olsson M, Tobler M, Healey M, Perrin C, Wilson M (August 2012). "A significant component of ageing (DNA damage) is reflected in fading breeding colours: an experimental test using innate antioxidant mimetics in painted dragon lizards". Evolution. 66 (8): 2475–83. doi:10.1111/j.1558-5646.2012.01617.x. PMID 22834746.

Further reading

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  • Boulenger GA. (1885). Catalogue of the Lizards in the British Museum (Natural History). Second Edition. Volume I. ... Agamidæ. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xii + 436 pp. + Plates I-XXXII. (Amphibolurus pictus, pp. 385–386).
  • Peters W. (1866). "Mittheilung über neue Amphibien (Amphibolurus, Lygosoma, Cyclodus, Masticophis, Crotaphopeltis) und Fische (Diagramma, Hapalogenys) des Kgl. Zoologischens Museums". Monatsberichte der Königlich Preussischen Akademie der Wissenschaften zu Berlin 1866: 86–96. (Amphibolurus pictus, new species, pp. 88–89). (in German).
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