Portrait

Description:

Portrait of the 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 (seen well here). The C-shaped macronucleus is transversely oriented (not well seen in this image). 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. Phase contrast illumination.