Heterotrophic ¯ agellates (Protista) from marine sediments of Botany Bay, Australia Author Lee, Won Je Author Patterson, David J. text Journal of Natural History 2000 34 483 562 journal article 1464-5262 Ploeotia vitrea Dujardin, 1841 (®gures 17f, 19c±e) Description. Cell oval, about 16±22 Mm long and 10±14 Mm wide, not ¯attened. This species has 10 longitudinal double raised ridges; four dorsally, two laterally, four ventrally. The anterior part of the cell is slightly obtuse and the posterior part of the cell is pointed. The anterior ¯agellum is as long as the cell, and the posterior ¯agellum is thick and twice as long as the cell. The ingestion organelle is well developed with a tiny protrusion at the top of the right-hand rod and tapers posteriorly. The nucleus is located in the right-hand side of the cell and the reservoir is in the left side. Rarely observed. Remarks. This species has been found in marine sites in subtropical and tropical Australia , Brazil , Fiji , Hawaii and USA , and the reported length range is from 16 to 25 Mm ( Farmer and Triemer, 1988 ; Larsen and Patterson, 1990 ; Patterson and Simpson, 1996 ). Ultrastructural studies of Ploeotia vitrea were conducted by Farmer and Triemer (1988) , and Larsen and Patterson (1990) . Our observations are in agreement with Larsen and Patterson (1990) . Ploeotia vitrea can be easily distinguished from other species in the genus by its 10 prominent ridges.