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.
The distribution of this family of slugs includes Nearctic, Palearctic and Oriental regions.[1]
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]
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:
The parasites of the Arionidae slugs include the Sciomyzidae.
This article incorporates public domain text from the reference.[1]
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.
