The Collaborative International Dictionary of English v.0.48:

Corydalus \Corydalus\ prop. n.
   The type genus of the Corydalidae. It includes the
   dobsonfly (Corydalus cornutus), whose aquatic larva, the
   hellgrammite, is used as bait in fishing.

   Syn: genus Corydalus, genus Corydalis.
        [WordNet 1.5 +PJC]

WordNet (r) 3.0 (2006):

Corydalus
    n 1: type genus of the Corydalidae [syn: Corydalus, genus
         Corydalus, Corydalis, genus Corydalis]