Lateral view of the haptorid ciliate,Askenasia volvox (Eichwald,1852) Kahl, 1930. The cell is spherical posteriorly and the anterior is a truncate cone.The cytostome is at the anterior apex.The cytostome is surrounded by an undulating line of granules (seen only in silver impregnated specimens).Somatic cilia are arranged in three (anterior,middle and posterior)girdles.The posterior girdle consists of long stiff bristles (seen here).The anterior cilia are directed forward and the middle girdle cilia are longer,curving backwards in a "sickle" configuration.These cilia produce the saltatory locomotion typical of this genus (they are seen well in this image).The posterior of the cell is unciliated.The central macronucleus is C-shaped. There is a single subequatorial contractile vacuole (seen here to viewer's right). From a freshwater pond near Boise, Idaho.Brightfield with closed condenser. This image was taken by William Bourland. He now uses a Zeiss Axioskop 2 with Spot Insight and Spot Flex CCD cameras (Diagnostic Instruments). Image copyright: William Bourland, image used under license to MBL (micro*scope).
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From the collection
Freshwater and Terrestrial Microbes of Idaho (USA) and Elsewhere
|Description of Askenasia volvox: Colonies spherical, consisting of several hundreds of individuals, 120-200 microns large. Cells oval, 8-12 microns long. Flagellum approximately 5 times so long as the cell. Nucleus just above the center. Contractile vacuole in the posterior end. Movement of the colony slowly rotating. |