Kurnaimonas celeris Lee nov. spec., 2015

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 : 67

Kurnaimonas celeris Lee nov. spec. ( Figs 1l , 4e–f )

Diagnosis: Cell oblong, 14 to 15 µm long, dorso-ventrally flattened and rigid. With two flagella of unequal length into wide ventral depression. With small protrusion separating insertion of flagella. Moving by fast swimming.

Etymology: The name refers to ‘fast’.

Observation: Cells are oblong, 14 to 15 µm long, dorso-ventrally flattened and rigid. The anterior part of the cell forms relatively a wide depression, which continues to a mid-ventral groove on the right side of the cell. The cells have a small protrusion, which is directed laterally and may separate the insertion of the flagella. The cells have two flagella, which are in the same strength and are not acronematic. The anterior flagellum inserts anterio-laterally into the ventral groove and is slightly longer than the cell. The posterior flagellum inserts just below the anterior flagellum, is about 2 times the length of the cell and appears to lie in the ventral groove. When the cells are moving, the anterior flagellum is directed to the front and beats in a sinewave, and the posterior flagellum beats also in a sinewave and directs posteriorly. The cells often contain large food particles in the posterior end of the cell. The cells move very fast by swimming. Rarely observed.

Remarks: This organism is similar to Pseudophyllomitus granulatus , but is distinguished because its posterior flagellum has an undulating beating pattern when swimming and because it is rigid and flattened. It is similar to Platychilomonas psammobia in being flattened and cell length, but P. psammobia has two rows of extrusomes and a coiled posterior flagellum when it is inmobile. This species may be distinguished from other swimming flagellates by its flagellar orientation. It was also reported from intertidal marine sediments in Korea under the name ‘Protist 2’ ( Lee 2002b).

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. 4. a – Carpediemonas membranifera; b – Kipferlia bialata; c – Discocelis saleuta, note a short flagellum; d – Metopion fluens, showing general appearance of cell, note shorter flagellum (arrow); e–f – Kurnaimonas celeris nov. spec., showing general appearance of cell; g – Pseudophyllomitus granulatus; h – Helkesimastix faecicola, showing general appearance and note short flagellum (arrow); i – Metromonas grandis, showing general appearance of cell and note the folded margin on the left side and short flagellum (arrow); j – Metromonas simplex, showing general appearance of cell and note short flagellum (arrow); k – Kiitoksia kaloista, showing two flagella and note short flagellum (arrow); l – Sinistermonas sinistrorsus nov. spec., showing general appearance of cell, and note flagellar insertion and beating pattern of anterior flagellum; m – Telonema subtilis, showing general appearance; n – Protist ‘1’. All micrographs are DIC images. Scale bar: 5 µm for all figures.