The Collaborative International Dictionary of English v.0.48:

Apod \Ap"od\, Apodal \Ap"o*dal\, a. [See Apod, n.]
   1. Without feet; footless.
      [1913 Webster]

   2. (Zool.) Destitute of the ventral fin, as the eels.
      [1913 Webster] Apod

WordNet (r) 3.0 (2006):

apodal
    adj 1: (of snakes and eels) naturally footless; "eels are
           apodal" [syn: apodal, apodous]