Oniscus

from WordNet (r) 3.0 (2006)

Oniscus
    n 1: type genus of the Oniscidae; woodlice that cannot roll into
         a ball [syn: {Oniscus}, {genus Oniscus}]

from The Collaborative International Dictionary of English v.0.48

Oniscus \Oniscus\ prop. n.
   The type genus of the {Oniscidae}, consisting of woodlice
   that cannot roll into a ball.

   Syn: genus {Oniscus}.
        [WordNet 1.5]