Infraciliature

Description:

Right lateral view of the haptorid ciliate, Acropisthium mutabile (Perty, 1852). The cell body is ovoid to cylindrical. The posterior tapers to a short point. The fixation and staining process swells the cells. The anterior end forms a blunt snout with an apical cytostome in the center of a bare area. Short trichites support the cytopharynx. A cluster of extrusomes (stained black here) protrudes from the cytostome. There is a girdle of longer cilia just posterior to the bare anterior snout. The closely packed kinetosomes of this circumoral ciliary girdle are angled obliquely to the long axis (seen well here). There are 22 widely spaced uniform longitudinal somatic kineties. The anterior halves of three dorsal kineties are made up of clavate (short club-shaped) cilia forming a dorsal brush (seen well in this view). Collected from freshwater pond near Boise, Idaho August 2004. This specimen is stained by a silver carbonate technique (see Foissner, W.Europ. J. Protistol.27,313-330;1991). Brightfield optics.