Jump to content

Helicidae: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
No edit summary
mNo edit summary
Line 79: Line 79:
* ''[[Theba]]'' <small>[[Antoine Risso|Risso]], 1826</small>
* ''[[Theba]]'' <small>[[Antoine Risso|Risso]], 1826</small>


A 2022 phylogenetic analyses proposed that all groups of the [[Maghreb]] radiation belonged to a single tribe, [[Thebini]], without support for a separate [[Otalini]] tribe.<ref name="Neiber">{{cite journal|author1=Marco T Neiber|author2=Ondřej Korábek|author3=Matthias Glaubrecht|author4=Bernhard Hausdorf|title=A misinterpreted disjunction: the phylogenetic relationships of the North African land snail ''Gyrostomella'' (Gastropoda: Stylommatophora: Helicidae)|journal=Zoological Journal of the Linnean Society| volume = 194| issue= 4|year= 2022| pages= 1236–1251|url= https://doi.org/10.1093/zoolinnean/zlab059|doi=10.1093/zoolinnean/zlab059}}</ref> The same study proposed a new tribe, '''[[Maculariini]] trib. nov.''' containing the genus ''[[Macularia]]'' due to the wide geographic disjunction between the western Alpine ''[[Macularia]]'' and the primarily Maghrebian [[Thebini]] tribe.<ref name = "Neiber"/>
A 2022 phylogenetic analysis proposed that all groups of the [[Maghreb]] radiation belonged to a single tribe, [[Thebini]], without support for a separate [[Otalini]] tribe.<ref name="Neiber">{{cite journal|author1=Marco T Neiber|author2=Ondřej Korábek|author3=Matthias Glaubrecht|author4=Bernhard Hausdorf|title=A misinterpreted disjunction: the phylogenetic relationships of the North African land snail ''Gyrostomella'' (Gastropoda: Stylommatophora: Helicidae)|journal=Zoological Journal of the Linnean Society| volume = 194| issue= 4|year= 2022| pages= 1236–1251|url= https://doi.org/10.1093/zoolinnean/zlab059|doi=10.1093/zoolinnean/zlab059}}</ref> The same study proposed a new tribe, '''[[Maculariini]] trib. nov.''' containing the genus ''[[Macularia]]'' due to the wide geographic disjunction between the western Alpine ''[[Macularia]]'' and the primarily Maghrebian [[Thebini]] tribe.<ref name = "Neiber"/>





Revision as of 19:32, 1 May 2022

Helicidae
Helix pomatia
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: Stylommatophora
Superfamily: Helicoidea
Family: Helicidae
Rafinesque, 1815
Type genus
Helix Linnaeus, 1758
Subfamilies

Helicidae is a large, diverse family of small to large, air-breathing land snails, sometimes called the "typical snails."

A number of species in this family are valued as food items, including Cornu aspersum (formerly Helix aspersa) the brown or garden snail, and Helix pomatia the "escargot".[1] The biologies of these two species in particular have been thoroughly studied and documented.

Shell description

The shells of these snails are mostly rather globular in shape. In some genera, such as Cepaea, the shells are brightly colored and patterned.

Anatomy

The animal is capable of complete retraction within the shell. The tail is without a mucous gland or projection.[2][unreliable source?]

The mouth is always provided with a jaw, which is striate, ribbed, sulcate or plicate, sometimes composed of several imbricating pieces. The radula is composed of many transverse horizontal series of teeth, the centrals tricuspidate, about the size of the laterals, laterals bicuspid, or tricuspid with the interior cusp obsolete, marginals usually wider than high, short with two or three small cusps.[2][unreliable source?]

In the soft parts the most obvious distinction is the lack of a caudal mucous pit, and their possessing a sculptured jaw. Typically, there is a distinction in the dentition, although in some species the lateral teeth take on a pseudozonitoid appearance; even in such cases the extreme marginals in Helix remain short and very obtuse.[2][unreliable source?]

This family of snails is defined by the anatomical presence of a diverticulum. Some genera within this family create and use love darts as part of their mating behavior. These snails have one dart apparatus. The dart sac has no accessory sac, and contains two tubular glands, inserted at the base of the dart sac.

In this family, the number of haploid chromosomes lies between 21 and 30 (according to the values in this table).[3]

Helicid snails for sale as food in Italy; from the front Eobania vermiculata, Cantareus apertus, and Helix sp.

Distribution

The family is native to Eurasia and belongs the Western Palearctic group.

However some species, notably Cornu aspersum, have been introduced and become established in numerous different areas worldwide.

Many accidental introductions happen because the eggs of most Helicidae are laid in the soil, and they may thus easily travel unnoticed along with landscaping plants.

Genera

Arianta arbustorum
Iberus gualtieranus alonensis
Cornu aspersum

The family Helicidae contains 3 subfamilies (according to molecular phylogenetic analyses[4][5][6]):

Subfamily Helicinae Rafinesque, 1815

In this subfamily the glands are divided. The love dart has four blades or vanes. There are usually two penial papillae.

Tribe Allognathini

Tribe Otalini

Tribe Thebini

A 2022 phylogenetic analysis proposed that all groups of the Maghreb radiation belonged to a single tribe, Thebini, without support for a separate Otalini tribe.[7] The same study proposed a new tribe, Maculariini trib. nov. containing the genus Macularia due to the wide geographic disjunction between the western Alpine Macularia and the primarily Maghrebian Thebini tribe.[7]


Subfamily Murellinae

Tribe Murellini Hesse, 1918

Subfamily Ariantinae Mörch, 1864

In this subfamily the glands are divided or undivided. The love darts contain two to four blades. There is only one penial papilla.

Incertae sedis

References

  1. ^ M.P. Kerney & R.A.D. Cameron. 1979. A field guide to the land snails of Britain and northwestern Europe. Collins, London.
  2. ^ a b c Tryon G. W. 1887 Manual of conchology; structural and systematic. With illustrations of the species. Second series: Pulmonata. Volume 3. Helicidae - Volume I. page 3–4.
  3. ^ Barker G. M.: Gastropods on Land: Phylogeny, Diversity and Adaptive Morphology. in Barker G. M. (ed.): The biology of terrestrial molluscs. CABI Publishing, Oxon, UK, 2001, ISBN 0-85199-318-4. 1-146, cited pages: 139 and 142.
  4. ^ Korábek, Ondřej; Petrusek, Adam; Neubert, Eike; Juřičková, Lucie (2015-05-01). "Molecular phylogeny of the genus Helix (Pulmonata: Helicidae)". Zoologica Scripta. 44 (3): 263–280. doi:10.1111/zsc.12101. ISSN 1463-6409.
  5. ^ Razkin, Oihana; Gómez-Moliner, Benjamín Juán; Prieto, Carlos Enrique; Martínez-Ortí, Alberto; Arrébola, José Ramón; Muñoz, Benito; Chueca, Luis Javier; Madeira, María José (2015-02-01). "Molecular phylogeny of the western Palaearctic Helicoidea (Gastropoda, Stylommatophora)". Molecular Phylogenetics and Evolution. 83: 99–117. doi:10.1016/j.ympev.2014.11.014. PMID 25485783.
  6. ^ Neiber, Marco T.; Hausdorf, Bernhard (2015-12-01). "Molecular phylogeny reveals the polyphyly of the snail genus Cepaea (Gastropoda: Helicidae)". Molecular Phylogenetics and Evolution. 93: 143–149. doi:10.1016/j.ympev.2015.07.022. PMID 26256642.
  7. ^ a b Marco T Neiber; Ondřej Korábek; Matthias Glaubrecht; Bernhard Hausdorf (2022). "A misinterpreted disjunction: the phylogenetic relationships of the North African land snail Gyrostomella (Gastropoda: Stylommatophora: Helicidae)". Zoological Journal of the Linnean Society. 194 (4): 1236–1251. doi:10.1093/zoolinnean/zlab059.
  8. ^ Nordsieck H. (2006). Higher classification of Helicoidea and the molecular analyses of their phylogeny. hnords.de Archived 2012-03-14 at the Wayback Machine, Accessed 20/06/12
  9. ^ Höltke, Olaf; Rasser, Michael W (2015). "Pseudochloritis insignis–a peculiar large land-snail from the Miocene of SW Germany: taxonomic status and census of morphologically related forms". Journal of Conchology. 42 (1): 1.