Discocelis punctata Larsen and Patterson, 1990

Patterson, Won Je Lee David J., 2000, Heterotrophic ¯ agellates (Protista) from marine sediments of Botany Bay, Australia, Journal of Natural History 34, pp. 483-562 : 550-551

Discocelis punctata Larsen and Patterson, 1990

(®gures 23l±m, 24g)

Description. Cell about 6 Mm long, disc-shaped, dorso-ventrally ¯attened, anteriorly concave and posteriorly convex. Two ¯agella emerge from a depression on the anterior end of the cell. The recurrent ¯agellum trails behind the gliding cell and is slightly longer than the cell. The shorter ¯agellum is less than 1 Mm long, is hard to see and is inactive. The nucleus is located anteriorly in the right half of the cell. There is a line of bodies around the margin of the cell. Glides smoothly in closely contact with the substratum. Rare. One cell observed.

Remarks. Discocelis punctata has been described by Larsen and Patterson (1990) and Tong et al. (1998) from marine sites in Brazil and Fiji, and our observations are in accord with their description except our cell is smaller than the previously reported cell dimensions of 6.5±9 Mm. The size of the cell observed here is between that of D. saleuta and D. punctata . Discocelis saleuta may have peripheral bodies (Vùrs, 1988; Larsen and Patterson, 1990) but these are not visible by light microscopy. We assign this individual to D. punctata because the peripheral granules were easy to see. Future work may indicate that we need to combine these two species. This species can be confused with the genus Metromonas in having one long recurrent ¯agellum and one short, inactive ¯agellum, but it is distinguished by the ¯atness of the cell, the pattern of movement, and the peripheral bodies.