Clautriavia cavus Lee and Patterson, 2000

Lee, Won Je & Patterson, David J., 2000, Heterotrophic flagellates (Protista) from marine sediments of Botany Bay, Australia, Journal of Natural History 34, pp. 483-562 : 550

Clautriavia cavus Lee and Patterson , n. sp.

(fi gures 24f, 25j, k. Type micrograph: fi gure 25j)

Diagnosis. Clautriavia , cell oval about 8 Mm long, fl attened, with subapically a shallow ventral groove and one trailing fl agellum emerging from a ventral depression.

Description. Cell outline oval, 8-10 Mm long, fl attened and rigid. One fl agellum directed posteriorly, emerges from a ventral subapical depression, is about 1.5-2 times the length of the cell and makes close contact with the substratum when the cell is gliding. Cells have a shallow, wide ventral groove which is easy to overlook. The ventral face of the cell appears to be slightly concave. The cell surface may be rather warty and food particles are seen in the posterior part of the cell. Cells glide slowly and smoothly with the posterior part slightly raised above the substratum. Often observed, but not in large numbers. Description based on the observations of eight cells.

Remarks. We assign this organism to the genus Clautriavia because it has general features of the genus: it is a gliding fl agellate with one trailing fl agellum and a midventral groove. Clautriavia is reminiscent of Protaspis and Allantion, but can be recognized from Protaspis by having only one fl agellum. This species is less easy to distinguish from Allantion because Clautriavia lacks a rostral prominence at the anterior end of the cell and has a concave ventral face. The genus Clautriavia to date contains two nominal species, C. mobilis (see Massart, 1900) and C. parva (see Schouteden, 1907). Clautriavia cavus differs from C. mobilis because C. mobilis is twice as large, has a relatively short fl agellum and has a nucleus at the right posterior of the cell. According to Patterson and Zölffel (1991), Clautriavia parva may be the gliding stage of Metromonas. This species may be the same as`Glissander’ by Tong (1994).