Source : Webster's Revised Unabridged Dictionary (1913)

Pluroderes \Plu*rod"e*res\, n. pl. [NL., fr. Gr. ? the side + ?
   the neck.] (Zo["o]l.)
   A group of fresh-water turtles in which the neck can not be
   retracted, but is bent to one side, for protection. The
   matamata is an example.