Echidna (E-kid'-na). Half-woman, half-serpent. ... I wonder how this name came to be applied to the spiny anteater of Australia.

American Heritage Dictionary:
echidna: [animal] having a spiny coat, slender snout, and an extensible sticky tongue used for catching insects. Also called spiny anteater. ETYMOLOGY: Latin, adder, viper, from Greek ekhidna, from ekhis.
Picture at http://www.sandiegozoo.org/images/animals/echidna.jpg

The echidna is one of only two species in a very exclusive group of mammals called monotremes, the other being the platypus. Itself an interesting word.