Amastigomonas mutabilis ( Griessmann 1913 ) Molina et Nerad 1991

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 : 120

Amastigomonas mutabilis ( Griessmann 1913) Molina et Nerad 1991 ( Figs 1b , 2b )

(= Rhynchomonas mutabilis Griessmann 1913 )

(= Thecamonas mutabilis Larsen et Patterson 1990 )

Observation: Cells are elliptical, 10 to 12 µm long, dorso-ventrally flattened and flexible, with a flexible sleeve around the base of the anterior flagellum. The anterior flagellum is about 0.2 times the cell length, and the posterior flagellum is slightly longer than the cell and attaches loosely in a slight groove. May have granules along side the posterior flagellum. Description based on observations of four cells.

Remarks: The genus Amastigomonas was created by De Saedeleer (1931) with A. debruynei and consists of 12 nominal species ( Molina and Nerad 1991, Mylnikov 1999, Lee and Patterson 2000). The genus Thecamonas has been considered a junior synonym of the genus Amastigomonas ( Molina and Nerad 1991; though see below). This species differs from the other species of these genera because of the granules located ventrally alongside the posterior flagellum, but some cells lack the granules, which were suggested to be distinctive by Larsen and Patterson (1990). Lee and Patterson (2000) mentioned that this species may be a synonym of Amastigomonas bermudensis . It has been reported from marine sites worldwide and previously reported length ranges from 7 to 20 µm in size (see Molina and Nerad 1991; Lee and Patterson 1998, 2000; Lee 2002b; Lee et al. 2003).

Recently Cavalier-Smith and Chao (2010) divided Amastigomonas into five genera: Amastigomonas , Thecamonas , Podomonas , Manchomonas , Multimonas . Although Cavalier-Smith and Chao (2010) ’s study is comprehensive and significant, all the characters mentioned may not be applicable when identifying species with a light microscope. Thus we prefer to follow the Molina and Nerad (1991) in this study.

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.