de Blainville, 1824
Internal shell approximately one-half the body-length. The mantle is relatively smooth, lacking pointed conical tubercles. The gill rachis lacks regularly arranged rows of tubercles; external penial sheath absent. Swimming does not occur.
The radula teeth are smooth. The jaw elements each bear three or more strong denticulations. The prostate gland, if present, is not conspicuous. The anus is situated midway along the length of the gill.
Source: Thompson, 1988.
The following species occurs in the region:
Berthella plumula