MORPHOLOGICAL STUDIES ON THREE CHINESE NEW RECORDS AND A RARE SPECIES OF HYPOTRICHOUS CILIATES

Three Chinese new record hypotrichous ciliates, namely Pleurotricha oligocirrata, Hemiamphisiella terricola terricola, Paraholosticha muscicola and a rare ciliate, Australocirrus aspoecki, were investigated based on their living morphology and ciliary pattern using both living observation and the protargol impregnated method. These specimens were collected from Shaanxi and Guangxi province in China. Detailed morphological descriptions of each species were provided, and thorough comparisons were made with previous populations. The results are summarized as follows: 1) the present population of Australocirrus exhibits smaller size compared to previous populations. Additionally, the numbers of micronuclei, dorsal kineties, adoral membranelles, and both left and right marginal cirri are fewer than those observed in previous populations. 2) compared with previous population, the Chinese population of Pleurotricha oligocirrata possesses fewer adoral membranelles but more frontoventral cirri. 3) the Chinese population of Hemiamphisiella terricola terricola closely resembles populations from Australia and Austria, but significantly differs from the population in Fiji in terms of the numbers of cirri in the amphisiellid cirral row, cirri in the right ventral row, and cirri in left and right marginal rows. 4) the Chinese population of Paraholosticha muscicola exhibits distinct differences in morphometric characterization compared to previous populations but shows similarities in living characterization. Furthermore, the SSU rDNA sequences of the above four species were compared with other populations of the same species, congeners, and molecular relatives for sequence similarity and the number of nucleotide differences. This study contributes to the accumulation and supplementation of diversity, morphological resources, and species resources of hypotrichous ciliates in China.