The Collaborative International Dictionary of English v.0.48:

Leiopelma \Leiopelma\ n.
   The type and sole genus of the family Leiopelmatidae. [Also
   spelled Liopelma.]

   Syn: genus Leiopelma, Liopelma, genus Liopelma.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Leiopelma
    n 1: type and sole genus of the family Leiopelmatidae [syn:
         Leiopelma, genus Leiopelma, Liopelma, genus
         Liopelma]