Definitions
Anal operculum
- (Taxon-specific: Family Cyatholaimidae) A small median process on dorsal surface of the anal somite protecting the anus. [Boxshall and Halsey, 2004]
- (Taxon-specific: Family Cyatholaimidae) Lid-like structure covering anus. (smooth, toothed). [Stachowitsch, 1992]