portrait

Description:

Portrait of Halteria oblonga (Kellicott, 1885;Kahl,1932), a spirotrich ciliate. The body is slightly elongate, rounded posteriorly and truncate anteriorly. There is a prominent anterior wreath of adoral membranelles that winds clockwise into the funnel-shaped peristome (seen in this image). The somatic ciliature is reduced to widely spaced longitudinal files of stout double cilia (seen well in this image). The posterior cilia are longer with a characteristic J-shape. These trail behind the organism during swimming, which is accomplished by the rapid beating of the AZM. The single peripheral contractile vacuole is located in the anterior 1/3 adjacent to the oral aperture. The single spheroid granular macronucleus and single round micronucleus are seen posterior to the contractile vacuole. Although Kahl (I. Wimpertiere oder Ciliata. 3. Spirotricha pp. 505-506, Gustav Fischer Verlag, 1932) describes endosymbiotic zoochlorellae, at least some of the algae in these individuals appear to have been ingested. Collected from organically enriched freshwater pond near Boise, Idaho June 2003. DIC optics.