Rhynchobodo formica ( Skuja 1948 ) Bernard et al. 2000

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 : 58

Rhynchobodo formica ( Skuja 1948) Bernard et al. 2000 ( Figs 1f , 3a–b )

Observation: The cell is spindle-shaped, about 40 µm long, and highly metabolic. The cell body appears to be twisted with a shallow longitudinal groove. Two flagella emerge from the subapical flagellar pocket and are longer than the cell. The anterior flagellum beats freely forwards and the posterior flagellum appears to wrap the cell body. The nucleus is located near the centre of the cell. Large granular bodies are seen below the centre of the cell and small particles are seen above the centre. The cell moves by swimming. One cell observed.

Remarks: The cell observed here is assigned to Rhynchobodo formica ( Skuja 1948) Bernard et al. 2000 . Skuja (1948) described R. formica (under the name of Cryptaulax formica ) as 20–35 µm long, very metabolic, with a twisted body, usually retains a spindle shape and has a shallow longitudinal groove. The cell observed is slightly larger but otherwise similar. Rhychobodo formica is distinguished from other Rhynchobodo species by its larger size and by greater flexibility. This species is similar to R. longiciliatus ( Skuja 1948) Bernard et al. 2000 in cell length (20–45 µm), but can be distinguished because R. longiciliatus has a narrow shape.

Bernard et al. (2000) synonymised Cryptaulax with Rhynchobodo . The genus Rhynchobodo contains 11 species of kinetoplastid flagellates with an apical ingestion apparatus, no papilla, a stiff anterior part of the body, and in some cases a spiral groove on the body. The distinctions are not clear, and many synonyms will probably be found.

Figures

Fig. 1. a – Chilomastix cuspidata, b – Rhynchopus amitus, c – Spironema multiciliatum, d – Psammosa unguis nov. comb., e – Apusomonas sp., f – Rhynchobodo formica, g – Mantamonas plastica, h – Roombia truncata, i – Thaumatomastix setifera, j – Ancyromonas impluvium nov. spec., k – Helkesimastix faecicola, l – Kurnaimonas celerisnov. spec., m – Sinistermonas sinistrorsus nov. spec., n – Kiitoksia kaloista, o – Protist ‘1’. Scale bar: 10 µm for all figures.

Fig. 3. a–b –Rhynchobodo formica; c –Massisteria marina, general appearance of cell showing pseudopodia and flagella (arrow); d–f – Cercomonas sp.; d – note two acronematic flagella; e – general appearance; f – note flagellar orientation; g–h – Roombia truncata, note cell attached to the substrate by the tip of the posterior flagellum and note extrusomes; i – Protaspa obliqua, note anterior protrusion;j–k – Thaumatomastix setifera, note spines around the body; j – general appearance of cell; k – ventral face showing a deep groove and pseudopodia; l–m – Ancyromonas sigmoides of different cells; l – note slightly thick anterior flagellum with acronematic tip and broad rostrum; m – note thick anterior flagellum and acute rostrum; n–p – Ancyromonas impluvium nov. spec., showing general appearance of cell and note flagellar insertion.All micrographs are DIC images with the exceptions of (d) and (p) which are phase contrast images. Scale bar: 5 µm for all figures.