Arionidae

Arionidae Temporal range: Miocene–Recent[1] PreꞒ Ꞓ O S D C P T J K Pg N
A live individual of the Spanish slug Arion vulgaris, in the wild
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Order:	Stylommatophora
Superfamily:	Arionoidea
Family:	Arionidae J.E. Gray, 1840[2]
Synonyms
Tetraspididae Hagenmüller, 1885

Arionidae, common name the "roundback slugs" or "round back slugs" are a taxonomic family of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea.

Distribution

The distribution of this family of slugs includes Nearctic, Palearctic and Oriental regions.[1]

Anatomy

Unlike some slugs, European Arionidae have no keel on the back.[1] The caudal mucous pit is above the tip of the tail.[1] The respiratory pore (pneumostome) is in front of the midpoint of the mantle.[1] The body length is up to 250 mm.[1] The mantle covers only a part of the body and lies in the anterior part.[1]

The jaw is odontognathic,[1] which means it is transversally ribbed. Radular teeth include: central tricuspid, lateral bi- or tricuspid, marginal bicuspid, all having broad bases.[1] Teeth are often accreted.[1] The digestive system forms 2 loops.[1] The heart, in relation to body axis, is titled to the left.[1] The kidney is circular (surrounding aorta).[1] Cephalic retractors tend to divide into separate branches attached independently to the posterior part of pallial complex.[1] The shell is strongly reduced in places, most often completely buried in the mantle, usually of loose crystals or plate-like.[1] Genitalia: the penis is present only in some species, epiphallus is present in nearly all of them.[1] Male copulatory organs are generally reduced, their role being taken over by a well-developed atrium and the epiphallus that produces spermatophores.[1]

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

Genera

Family Arionidae has no subfamilies according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005.

The type genus of the family is Arion Férussac, 1819

Genera within the family Arionidae include:

• Anadenulus Cockerell, 1890[4]
• Arion Férussac, 1819
• Ariunculus Lessona, 1881
• Carinacauda Leonard, Chichester, Richart & Young, 2011[5]
• Geomalacus Allman, 1843
• Gliabates Webb, 1959[6]
• Hesperarion Simroth, 1891[7]
• Letourneuxia Bourguignat, 1866
• Magnipelta Pilsbry, 1953[8]
• Prophysaon Bland & W. G. Binney, 1873[9]
• Securicauda Leonard, Chichester, Richart & Young, 2011[5]
• Udosarx Webb, 1959[10]
• Zacoleus Pilsbry, 1903[11]

Parasites

The parasites of the Arionidae slugs include the Sciomyzidae.

References

This article incorporates public domain text from the reference.[1]

1. "Family summary for Arionidae". AnimalBase, last change 12-06-2009, accessed 4 August 2010.
2. Gray, J.E. (1840). "[Shells of molluscous animals]". Synopsis of the contents of the British Museum (42 ed.). London: British Museum. p. 148.
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. (In the reference specified as Ariononae.)
4. Cockerell (1890). Ann. Mag. nat. Hist. (6)6: 278.
5. Leonard, William P.; Chichester, Lyle; Richart, Casey H.; Young, Tiffany A. (2011). "Securicauda hermani and Carinacauda stormi, two new genera and species of slug from the Pacific Northwest of the United States (Gastropoda: Stylommatophora: Arionidae), with notes on Gliabates oregonius Webb 1959" (PDF). Zootaxa. 2746: 43–56. doi:10.11646/zootaxa.2746.1.4.
6. Webb (1959). Gastropodia 1(3): 22.
7. Simroth (1891). Malak. Bl. (N.S.) 11: 111.
8. Pilsbry H. A. (1953). Nautilus 67: 37.
9. Bland & Binney W. G. (1873). Ann. Lyceum nat. Hist. N. York 10(3): 921.
10. Webb (1959). Gastropodia 1: 22.
11. Pilsbry H. A. (1903). Proc. Acad. nat. Sci. Philad. 55: 626.

External links

• Round back slugs (Arionidae) on weichtiere.at.