The Collaborative International Dictionary of English v.0.48:

Mudfish \Mud"fish`\, n. (Zool.)
   (a) The European loach.
   (b) The bowfin (Amia calva).
   (c) The South American lipedosiren, and the allied African
       species (Protopterus annectens). See Lipedosiren.
   (d) The mud minnow, a fish of the genus Umbra or family
       Umbridae.
   (e) any fish which lives in muddy waters, such as the
       mummichog, a killifish.
       [1913 Webster +PJC]

The Collaborative International Dictionary of English v.0.48:

Amia \Am"i*a\, n. [L., fr. Gr. ? a kind of tunny.] (Zool.)
   A genus of fresh-water ganoid fishes, exclusively confined to
   North America; called bowfin in Lake Champlain, dogfish
   in Lake Erie, and mudfish in South Carolina, etc. See
   Bowfin.
   [1913 Webster]