Ciliate Biology Laboratory, Sri Guru Tegh Bahadur Khalsa College, University of Delhi, Delhi 110 007, India.
Eur J Protistol. 2013 May;49(2):283-97. doi: 10.1016/j.ejop.2012.08.009. Epub 2012 Dec 4.
The freshwater ciliate Cyrtohymena (Cyrtohymenides) shii (Shi et al., 1997) Shao et al., 2012 (Hypotricha, Oxytrichidae), isolated from Barsey Rhododendron Sanctuary of The Eastern Himalayas, is slightly flexible, measures about 150 μm × 50 μm in life and possesses citrine cortical granules randomly distributed singly and in small clusters. Cells of our Indian population have five or six dorsal kineties arising from multiple fragmentation of the third dorsal anlage. The subgenus Cyrtohymenides includes species with multiple dorsal kinety fragmentation namely C. (C.) aspoecki (type species), C. (C.) australis, and the present species. Ventral morphogenesis of the genus Cyrtohymena has been reported only for the type species C. muscorum. Notable features of the Indian population include formation of frontal anlagen from four parental cirri, two more parental cirri possibly contribute to these anlagen later, and the formation of primary primordia which later split transversely to form two sets, one for each daughter cell. 18S rDNA sequence of the Indian population matches with those of two populations of C. citrina; it also clusters with Afrokeronopsis aurea, a neokeronopsid, with which it interestingly shares some morphological features, supporting the CEUU hypothesis.
淡水纤毛虫 Cyrtohymena (Cyrtohymenides) shii (Shi 等人，1997 年；Shao 等人，2012 年)，隶属于 Hypotricha 科 Oxytrichidae 属，从喜马拉雅山东部的巴塞尔自然保护区采集而来，形态略有弹性，活体大小约为 150μm×50μm，具有金黄色皮层颗粒，随机单个或小簇状分布。我们采集的印度种群的细胞具有五或六个背毛带，由第三背毛基片多次断裂产生。Cyrtohymenides 亚属包含多个背毛带发生断裂的物种，即模式种 C. (C.) aspoecki、C. (C.) australis 和本种。仅对模式种 C. muscorum 进行过 Cyrtohymena 属的腹毛发生形态研究。印度种群的显著特征包括从四个亲代纤毛形成额毛基片，可能后来又有两个亲代纤毛有助于这些额毛基片的形成，以及初级原基的形成，原基后来横向分裂形成两组，每组为一个子细胞。印度种群的 18S rDNA 序列与两种 C. citrina 种群相匹配；它还与 Afrokeronopsis aurea 聚在一起，后者是一种新副栉虫目纤毛虫，有趣的是，它与 Afrokeronopsis aurea 共享一些形态特征，支持了 CEUU 假说。
