The Collaborative International Dictionary of English v.0.48:

Aperea \A*pe"re*a\, n. [Native name.] (Zool.)
   The wild Guinea pig of Brazil (Cavia aperea).
   [1913 Webster]

WordNet (r) 3.0 (2006):

aperea
    n 1: South American cavy; possibly ancestral to the domestic
         guinea pig [syn: aperea, wild cavy, Cavia porcellus]