Right side

Kuvaus:

Portrait (right side) of the small Odontostome ciliate, Mylestoma pusillum (Kahl,1932). M. pusillum has a rigid armored pellicle typical of the Odontostomes. The cell is laterally compressed. The truncate posterior lacks spines, distinguishing Mylestoma pusillum from Epalxa, Saprodinium and Atopodinium. The dorsum is broadly convex and the ventral surface flattened. There is a deep longitudinal pellicular groove on the left side (seen well in this image). The tooth-like projections anterior and posterior to the cytostome are seen in this image. The adoral zone of membranelles is seen in this image as an area of transverse striation. The somatic ciliature is strongly reduced to a few perizonal kineties anterior to the cytostome (seen in this image) and two sparse groups of long cirri posteriorly, one on either side of the longitudinal pellicular groove. There is a single elliptical macronucleus. There is a single posterior contractile vacuole (seen well in this image). Yellow-brown refractile granules are seen in the cytoplasm. Like other Odontostomes, Mylestoma is sapropelic. Collected from bottom sediment of a freshwater aquaculture tank at a Koi farm near Boise, Idaho December 2003. DIC optics.