in vivo;optical section

Description:

Portrait of the nassulid ciliate, Nassula picta Nassulides pictus (Greeff, 1888) Foissner, Agatha and Berger, 2002.The cell shape is broadly ovate and slightly flattened.The cell is brightly colored by food vaculoes containing cyanobacteria and algae in various stages of digestion.Cortical alveolae and mucocysts form a distinct pellicular rim (seen here).The cytostome, located in the anterior 1/4 of the cell, is supported by stout nematodesmata.The single contractile vacuole is equatorial. The spherical macronucleus and adjacent micronucleus are central.The somatic kineties are bipolar.There is a synhymenium or hypostomial frange compsed of rectangular groups of kinetids in three rows.The group closest to the cytostome is largest. These groups (7-8) of kinetids are arrange obliquely to the somatic kineties. The obliquity of the hypostomial frange elements distinguishes Nassulides from the otherwise similar genus Nassula in which the elements are perpendicular to the long axis of the cell.The left somatic kineties are interrupted by the synhymenium.The synhymenium extends only slightly onto the dorsum (unlike Obertrumia). Collected from an organically enriched rainwater pool with abundant decaying grass in Boise, Idaho. January 2006.DIC.