Anisonema acinus Dujardin 1841

Aydin, Esra Elif & Lee, Won Je, 2012, Free-living Heterotrophic Flagellates from Intertidal Sediments of Saros Bay, Aegean Sea (Turkey), Acta Protozoologica 51 (2), pp. 119-137 : 123

Anisonema acinus Dujardin 1841 ( Figs 1p , 2m )

Observation: Cell is ovate, 23 µm long and flattened with a chisel-shaped ingestion organelle. Two flagella of unequal length emerge from a reservoir on the left side. The anterior flagellum beats actively with a sweeping motion and is about the same length with the cell. The posterior flagellum forms a hook after leaving the reservoir with a strong and broad distal region, lies on the ventral side, bends backwards and the proximal emergent part is readily visible only during jerking movement. The nucleus is located at the right side and the vacuole is at the left side and empties into the reservoir. One cell found.

Remarks: Anisonema acinus resembles Dinema validum Larsen et Patterson 1990 and Dinema platysomum (Skuja 1939) Lee et Patterson 2000 in general outline but Anisonema is distinguished from Dinema because Dinema is flexible with a thickened pellicle. Anisonema acinus resembles A. glaciale Larsen et Patterson 1990 and A. costatum Christen 1962 , but A. acinus differs from A. glaciale with its lack of frozen behaviour and with the location of its nucleus. Anisonema acinus is distinguished from A. costatum by the well developed spiral ribs of the pellicle of A. costatum . Anisonema prosgeobium was regarded as a junior synonym of A. acinus by Lee and Patterson (2000). This species is reported from marine sites in Australia, Danish Wadden Sea, and Fiji with the cell length of 21 to 48 µm and from Kuwait with the cell length of 35 to 61 µm ( Larsen 1987, Larsen and Patterson 1990, Al-Qassab et al. 2002, Lee et al. 2003, Lee 2006a, Lee 2012, Al-Yamani and Saburova 2010).

Figures

Fig. 1. a – Actinomonas mirabilis/Pteridomonas danica; b – Amastigomonas mutabilis; c – Ancyromonas micra; d – Bicosoeca conica; e – Bordnamonas tropicana; f – Caecitellus parvulus; g – Cafeteria minuta; h – Cafeteria roenbergensis; i – Cyranomonas australis; j – Developayella elegans; k – Discocelis saleuta; l – Goniomonas amphinema; m – Goniomonas pasifica; n – Kiitoksia ystava; o – Dinema platysomum; p – Anisonema acinus; q – Heteronema exaratum; r – Heteronema ovale; s – Kathablepharis remigera; t – Notosolenus canellatus; u – Massisteria marina; v – Metromonas grandis; w – Neobodo designis; x – Neobodo saliens; y – Percolomonas similis. Scale bar: 10 μm for all figures.

Fig. 2. a – Actinomonas mirabilis/Pteridomonas danica; b – Amastigomonas mutabilis; c – Ancyromonas micra; d – Bicosoeca conica; e – Caecitellus parvulus, note the mouth on the left-hand side; f – Bordnamonas tropicana; g – Cafeteria roenbergensis; h – Cyranomonas australis; i – Developayella elegans; j – Discocelis saleuta; k – Goniomonas amphinema; l – Cafeteria minuta, feeding cell; m – Anisonema acinus, dorsal view, note the ingestion organelle; n – Dinema platysomum, ventral view showing surface striations; o – Goniomonas pacifica; p – Heteronema exaratum, ventral view, general appearance of cell; q – Kathablepharis remigera; r – Massisteria marina; s – Neobodo saliens; t – Neobodo designis; u–v – Heteronema ovale, same cell; u – general appearance; v – extended cell. All micrographs are DIC images. Scale bar: 5 μm for all figures.