A new hypotrich ciliate, Oxytricha xianica sp.nov., with notes on the morphology and phylogeny of a Chinese population of Oxytricha auripunctata Blatterer & Foissner, 1988(Ciliophora, Oxytrichidae)

The morphology and infraciliature of the new hypotrichous ciliate, Oxytricha xianica sp.nov., and a Chinese population of Oxytricha auripunctata Blatterer & Foissner, 1988, are investigated using live observation and protargol staining.Oxytricha xianica sp.nov.is defined by the body size 85-130 μm × 30-50 μm in vivo, the typical oxytrichid 18 frontoventral-transverse cirri, cortical granules absent, undulating membranes reduced or absent, three caudal cirri, dorsal kineties in Oxytricha pattern, and two ellipsoidal macronuclear nodules.The Chinese population of O.auripunctata differs slightly from other populations in the arrangement and color of cortical granules and position of anterior end of dorsal kinety 4.Phylogenetic analyses based on SSU-rDNA sequences support the assertion that O.auripunctata belongs to Oxytricha and Oxytrichidae.