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The morphology and infraciliature of a new ciliate, Kiitricha minuta n. sp., isolated from the Yellow Sea, were investigated using live observation and protargol impregnation. Kiitricha minuta represents a third member of the rarely known order Kiitrichida. It is unique in the subclass Hypotrichia in having many rows of small uniform cirri along the right side of the body and the dorsal kineties composed of dikinetids, most of which bear two cilia. Kiitricha minuta n. sp. is ovoid and measures about 60 × 45 μm in vivo. It has a huge buccal cavity occupying about 80% of the body length, numerous body extrusomes, one macronucleus and two micronuclei, 27–27 adoral membranelles, 9–12 frontoventral cirral rows, a submarginal row of 7–9 cirri, 6 or 7 transverse cirri, and roughly 7–9 dorsal kineties. This new species differs distinctly from its only congener Kiitricha marina by its smaller size (60 μm vs. 80–150 μm), the presence of body extrusomes (vs. absent), the different macronuclear pattern (one vs. two nodules), and the lower number of frontoventral cirral rows (9–12 vs. 21–26), which terminate at the anterior two-thirds of body (vs. extend to the posterior). The new term “submarginal cirral row” is introduced to distinguish from the marginal cirral row in typical hypotrichs sensu lato. Based on our new observations and the literature, an improved diagnosis for the genus Kiitricha is provided and its phylogenetic importance is discussed. [ABSTRACT FROM AUTHOR]

The morphology and infraciliature of a new ciliate, Tunicothrix rostrata n. g., n. sp., isolated from the Yellow Sea, are investigated using live observation and protargol impregnation. Tunicothrix rostrata measures about 160 × 40 μm in vivo, and has a frontal beak-like protrusion, a conspicuous cortical alveolar layer, two right marginal rows, and usually three distinct midventral pairs. The discovery of T. rostrata enables us to reconsider the classification of Erniella wilberti, a curious ciliate with obscure midventral pairs. Both species are highly similar in overall appearance and nuclear and ciliary pattern. Thus, they are united in a new genus of the family Urostylidae, Tunicothrix, and E. wilberti is transferred to Tunicothrix: Tunicothrix wilberti Lin and Song, 2004 n. comb. By contrast, Erniella filiformis, type species of Erniella, has several ventral rows and does not belong to the urostylids. Tunicothrix rostrata is easily distinguished from T. wilberti by its beak-like anterior protrusion and by the distinctly elongated right marginal row 2, which curves anteriorly on the dorsal side of the cells. Tunicothrix is closely related to Parabirojimia, differing by the invariably two (vs. five–eight) right marginal rows and the conspicuous (vs. ordinary) alveolar layer, a unique feature in urostylid ciliates. [ABSTRACT FROM AUTHOR]

Studies Holosticha hamulata and Holosticha heterofoissneri, two urostylid ciliates from intertidal sediments of the Yellow Sea. Morphometric data; Occurrence and ecology; Comparison between populations of Holostica heterofoissneri; Location of the contractile vacuole as a taxonomic feature.