The Collaborative International Dictionary of English v.0.48:

Amphiuma \Am`phi*u"ma\ ([a^]m`f[i^]*[=u]"m[.a]), n. (Zool.)
   A genus of amphibians, inhabiting the Southern United States,
   having a serpentlike form, but with four minute limbs and two
   persistent gill openings; the Congo snake.
   [1913 Webster]

WordNet (r) 3.0 (2006):

amphiuma
    n 1: aquatic eel-shaped salamander having two pairs of very
         small feet; of still muddy waters in the southern United
         States [syn: amphiuma, congo snake, congo eel, blind
         eel]