From The Collaborative International Dictionary of English v.0.48 :
Mustelus \Mustelus\ prop. n.
A genus of sharks including certain of the smooth dogfishes.
Syn: genus Mustelus.
[WordNet 1.5]
From WordNet (r) 3.0 (2006) :
Mustelus
n 1: smooth dogfishes [syn: Mustelus, genus Mustelus]