Portrait

Description:

Portrait of the sessile solitary peritrich ciliate, Propyxidium (Corliss, 1979). The zooid is an elongate inverted bell shape. The short stalk is noncontractile. There is no distinct peristomal lip (unlike the similar Rhabdostyla). The prominent tilted peristomal disc is elevated on a broad stalk. The C-shaped macronucleus is transversely oriented (the two ends of the macronucleus are seen in cross-section here).The single contractile vacuole is in the posterior half of the cell. Propyxidium replaced the preoccupied Pyxidiella. Collected from a freshwater pond near Boise, Idaho. Brightfield illumination.