Porcellionidae

Porcellionidae
Porcellio scaber
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Isopoda
Suborder:	Oniscidea
Family:	Porcellionidae Brandt & Ratzeburg, 1831

Porcellionidae is a terrestrial family of the order Isopoda. The species classified here cannot roll into a ball, as opposed to the species of family Armadillidiidae, which can.

This family contains 530 species, found on every continent except Antarctica.

The ventral plate of the thoracic exoskeleton flare out slightly over the legs. This "flare" is called the epimeron. The uropods, antenna-like structures at the back of the specimen, are flattened out and spearlike, and extend beyond the last exoskeletal plate.

The family contains 19 genera, and two further genera (Inchanga and Mahehia) may be included.

...
Wikipedia