Cephalopyge trematoides


Cephalopyge trematoides is a pelagic species of nudibranch. A free-swimming marine gastropod in the family Phylliroidae. Cephalopyge trematoides is the only known species in its genus.

Etymology

Cephalopyge is a contraction of cephalus and pyge referring to the position of the anus close to the head. The species epithet trematoides expresses a likeness to flukes.

Description

C. trematoides grows to 2.5 cm in length. It swims at approximately 12 cm/s, by passing several undulatory waves down its body each second. It is flattened and transparent; its internal organs are visible.

Pelagic nudibranchs

Of the approximately 3000 species of nudibranch, the vast majority are benthic, only a couple are neustonic, and C. trematoides is very unusual in that it is pelagic. It is estimated to be one of only five planktonic nudibranch species.
Further information :