Abstract:
Hypotrichs, the most complex and evolved ciliate group, are widely found in various habitats. The morphological studies on the ciliates have mainly focused on freshwater of limited provinces, the Yellow and Bohai Seas and the South China Sea coast, and few reports are available from the Yangtze Estuary area. The morphology of five hypotrichous ciliates isolated from Yangtze River area,
Bakuella incheonensis,
Histriculus histrio,
Pseudokeronopsis rubra,
Pseudokeronopsis flava, and
Pseudourostyla cristata, were investigated using living observation and protargol staining methods.
Bakuella incheonensis and
H. histrio were first reported in China. Detailed redescriptions including the living characteristics and the infraciliature were supplemented. Results showed that the Jiangsu population of
B. (
B.)
incheonensis had a bigger size, more adoral membranelles and frontoterminal cirri than the original Korean population; the Shanghai population
of
H. histrio differed from some foreign populations in body length; the Jiangsu population of
P. rubra presented a larger size range than the Qingdao population; the Shanghai population of
P. flava had more frontal cirri compared with the Zhanjiang population; the Shanghai population of
P. cristata owned more macronuclear nodules than the Japanese population. This work enriches our understanding of the hypotrichs diversity in China.