Hemistasia phaeocysticola ( Scherffel 1900 ) Elbrächter et al. 1996

Lee, Won Je, 2015, Small Free-Living Heterotrophic Flagellates from Marine Sediments of Gippsland Basin, South-Eastern Australia, Acta Protozoologica 54 (1), pp. 53-76 : 57

Hemistasia phaeocysticola ( Scherffel 1900) Elbrächter et al. 1996 ( Figs 2h–i )

Observation: Cells are oblong, 27 to 33 µm long, less metabolic, and are not flattened with a spiral groove. The cells form a constant shape (oblong) rather than highly metabolic, and form a flexible anterior papillum containing a tubular ingestion organelle. The nucleus is located in the centre of the cell. There are small particles throughout the cell. The posterior flagellum is slightly longer than the anterior flagellum and the cell. During swimming the cells rotate. Two cells were observed.

Remarks: This species has been reported from marine sites in Australia, Germany, Wadden Sea and Korea, with cell lengths of 12–25 µm ( Scherffel 1900; Griessmann 1913; Elbrächter et al. 1996; Tong et al. 1998; Lee and Patterson 2000; Al-Qassab et al. 2002; Lee 2002b, 2006b). The genus Hemistasia resembles Entomosigma , Rhynchobodo and Cryptaulax . The latter two genera have been synonymised ( Bernard et al. 2000). Hemistasia is very similar to Rhynchobodo , but can be distinguished by its anterior papillum. The cells observed here are similar to Rhynchobodo thiophila sensu Skuja 1956 in cell length and general appearance, but can be distinguished by the presence of the flexible anterior papillum.

Figures

Fig. 2. a – Chilomastix cuspidata, showing general appearance of cell; b – Goniomonas amphinema, showing general appearance of cell; c – G. pacifica, note two flagella diverging; d – Percolomonas similis, note ventral groove; e – Bodo platyrhynchus; f – Neobodo curvifilus; g – N. saliens; h–i – Hemistasia phaeocysticola, note a papillum (arrow); j – Bordnamonas tropicana, showing general appearance and mouth (arrow); k – Rhynchomonas nasuta; l–o – Rhynchobodo simius; l – tubular ingestion organelle (arrow); m, o – showing groove; n – general appearance of cell; p–q – Rhynchopus amitus; r–s – Spironema multiciliatum; t – Amastigomonas debruynei, general appearance of cell; u – Amastigomonas mutabilis, note anterior flagellum projecting from sleeve and recurrent flagellum; v – Apusomonas sp.; w – Psammosa unguis nov. comb., general appearance of cell; x–y – Mantamonas plastica; x – note anterior flagellum (arrow) and y – ventral depression.All micrographs are DIC images. Scale bar: 5 µm for all figures.