Perkinsidae Levine 1978 Incertae

Lee, Won Je, 2019, Small Free-Living Heterotrophic Flagellates from Marine Intertidal Sediments of the Sydney Region, Australia, Acta Protozoologica 58 (4), pp. 167-189 : 180

Perkinsidae Levine 1978 Incertae sedis Psammosa unguis ( Patterson et Simpson, 1996) Lee, 2015

Figs 1n, 2p

Description: Cells are 8–13 µm long, bean-shaped in profile and somewhat flattened. The cells may have longitudinal lines of granules. Two flagella insert at right angles on one flat side about one third of the way down the cell. The anterior flagellum is nearly the length of the cell, inserts at the end of a deep, triangular curving depression. It is directed laterally and posteriorly. The posterior flagellum inserts at the top of a shallow longitudinal groove, is nearly two times the length of the cell, and is directed posteriorly. Some cells have large vacuoles containing eukaryotic prey material. The cells typically swim rapidly, usually in contact with the substrate. The cells erratically flip from one side to the other when swimming. Not common.

Remarks: This species has been reported from hypersaline sites and marine sediments in Shark Bay with cell length from 7 to 10 µm ( Patterson and Simpson 1996, Al-Qassab et al. 2002, Lee 2002b, Aydin and Lee 2012) under the name of Colpodella unguis. Copodella unguis was transferred to Psammosa by Lee (2015) because their cell shape and flagellar orientation are very similar. Psammosa unguis and P. pacifica share similar characters such as cell shape (elongated reniform), flagellar orientation and cell length (P. unguis 7–10 µm, Psammosa pacifica 7–8 µm). Only the difference is the proportion of anterior left part (P. unguis about 2/3 CL, P. pacifica about 1/3 CL) ( Okamoto et al. 2012). Later Cavalier-Smith (2018) created a genus Colpovora for Colpodella unguis. However, I regard Colpovora unguis as a junior synonym of Psammosa unguis. The distinctive division cysts of P. unguis have not been observed to date.

Figures

Fig. 2. (a)–(b) Mastigamoeba psammobia, (a) general appearance of cell, note cytoplasms drawn from the posterior end, (b) general appearance of different cell and note pseudopodia. (c) Hexamita inflata, general appearance, note the nucleus. (d) Trepomonas agilis, general appearance of cell. (e) Chilomastix cuspidata, showing general appearance. (f) Stephanopogon sp., showing general appearance. (g) Saepicula pulchra, showing general appearance of cell. (h)–(j) Goniomonas amphinema. (h) Form I, (i) Form II, (j) Form III, note flagellar ar- rangement. (k) Roombia truncata, note attached cell to the substrate by the tip of the posterior flagellum, note extrusomes, surface striations and deep gullet. (l) Telonema subtilis, showing general appearance. (m) Harpagon descissus, general appearance of cell. (n)–(o) Spironema multiciliatum, (n) general appearance of cell, (o) note the kinetics. (p) Psammosa unguis, general appearance of cell. (q) Bicosoeca conica, general appearance of cell. (r) Apusomonas proboscidea, genera appearance of cell, note the V-shaped structure on dorsal face. All micrographs are DIC images except for (b), which is phase contrast images. Scale bar in (r) = 10 μm for all figures.