The Collaborative International Dictionary of English v.0.48:

Crebricostate \Cre`bri*cos"tate\ (kr[=e]`br[i^]*k[o^]s"t[asl]t),
   a. [L. creber close + costa rib.] (Zool.)
   Marked with closely set ribs or ridges.
   [1913 Webster]