Philomycidae


Philomycidae are a family of air-breathing land slugs. They are terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea.
The family Philomycidae has no subfamilies.

Distribution

Slugs in this family are found in China, Japan, the East Indies, central and eastern North America, and through Central America into northern South America.

Anatomy

Members of this family most obviously differ from related slugs in that their mantles are broadly rounded, and very large, covering the entire body.
Pilsbry stated that "the enormously developed mantle, the large empty shell sac, and the insertions of the free retractor muscles along the margins of the foot cavity, instead of dorsally as in the Arionidae are special to the Philomycidae".
A further anatomical oddity of the group, shared with certain helicid and zonitid snails, is their creation and use of calcareous love darts during mating.
In this family, the number of haploid chromosomes lies between 21 and 30.

Genera

Genera within the family Philomycidae include:
A cladogram based on sequences of cytochrome-c oxidase I genes showing phylogenic relations of genera in the family Philomycidae by Tsai & Wu :
Arion and Deroceras were used as outgroup.