Morphological and phylogenetical studies on a new soil hypotrich ciliate: Kahliella matisi spec. nov. (Hypotrichia, Kahliellidae)

The morphology, ontogenesis, encystment, and 18S rRNA gene sequence of a new soil hypotrich ciliate, Kahliella matisi, were studied. Main characteristics of K. matisi are: (1) two short and six longitudinal cirral rows right of the adoral zone of membranelles and four longitudinal rows left of it; (2) three dorsal kineties, of which kinety 1 extends along the left cell margin, kinety 2 runs in a slightly sigmoidal line, and kinety 3 is distinctly shortened posteriorly. Ontogenesis is similar to that in congeners, especially in the development of the marginal rows and long dorsal kineties, the preservation of some old cirral rows after division, and the direction of the neokinetal wave. However, there are some peculiarities: (1) reorganization of the proximal parental adoral membranelles; (2) splitting of opisthe's anlage II into the cirral streak II and III; and (3) formation of the parental cirral row R3 from anlagen IV and V. During encystment, the body diminishes and becomes globular, the nuclear apparatus is reorganized, and the ciliature is resorbed. In our molecular phylogenies, the family Kahliellidae is polyphyletic and the position of K. matisi is rather poorly resolved, indicating a relationship with oxytrichids.