Capitanio FL, Daponte MC and Esnal GB.

Antarctic Science 15 (4): 476–482 (2003) doi:10.1017/S0954102003001585

The classification of Antarctic appendicularians: the Oikopleura gaussica group

Proposes that O. gaussica, O. valdiviae, O. drygalskii, and O. weddelli actually form a single species. It has oral gland cells, and a variable (8~14) number of subchordal cells, on the right (ventral) side of the tail.