Dorsal infraciliature

Description:

Infraciliature (dorsal view) of the prorodontid ciliate, Placus luciae (Kahl,1926) Kahl,1930. The cell is ovoid and slightly laterally compressed. The pellicle has broad slightly spiral ridges separated by narrow furrows.In this preparation the reticulate pattern of the ridges is seen. Fine transverse striations cross the narrow furrows between the somatic kineties to a darkly stained longitudinal fibril on the right margin of the ridges. The small oval oral aperture is apical anterior, surrounded by a ring of unciliated kinetosomes. The cytopharynx is supported by fine trichites. The somatic ciliature uniform, with cilia. There is a "brush" , about 1/4 to 1/3 cell length, composed of a double parallel row of kinetosomes bearing longer cilia. This arises adjacent to the oral aperture and terminates at a ventral circular "pit" which has a supporting ring of transversely oriented trichites. The function of this structure is unknown . The ovoid macronucleus is centrally located. The contractile vacuole is posterolateral. Collected from a slow-flowing freshwater stream near Boise, Idaho.Stained by the silver carbonate technique (see Foissner, W.Europ. J. Protistol.27,313-330;1991) . Brightfield.