A new contribution to the taxonomy and phylogeny of the ciliate genus Spirostomum(Alveolata,Ciliophora,Heterotrichea),with comprehensive descriptions of two species from wetlands in China  

作　　者：Yong Chi Zhe Wang Tingting Ye Ya Wang Junli Zhao Weibo Song William A.Bourland Xiangrui Chen 

机构地区：[1]Institute of Evolution&Marine Biodiversity,and College of Fisheries,Ocean University of China,Qingdao,266003,China [2]School of Marine Sciences,Ningbo University,Ningbo,315800,China [3]Weishan Fishery Development Service Center,Jining,277600,China [4]Department of Zoology,Faculty of Science,Charles University,Prague,12843,Czech Republic

出　　处：《Water Biology and Security》2022年第2期23-37,共15页水生生物与安全（英文）

基　　金：the National Natural Science Foundation of China(No.31970398 and 32030015);a Czech Science Foundation grant(No.19-19297S).

摘　　要：Species of the ciliate genus Spirostomum Ehrenberg,1834 are distributed worldwide and have a research history spanning more than two centuries.However,species delimitation and phylogenetic relationships within this genus are still uncertain due to the paucity of stable morphologic characters for species separation and the unavailability of accompanying morphological data for most molecular sequences in public databases.In the present study,S.yagiui Shigenaka,1959(three populations)and S.caudatum(Müller,1786)Delphy,1939(one population)were investigated using morphological and molecular methods for the first time in China.Detailed morphological data for the two species were documented,and improved diagnoses were supplied based on a combination of previous studies and the current work.It should be highlighted that there were three different atypical morphotypes identified in a Ningbo population of S.yagiui which may represent various stages in conjugative reproduction.Molecular phylogenies based on 18S,ITS1-5.8S-ITS2,and 28S rRNA gene sequences show that the genus Spirostomum is monophyletic,however,the internal relationships inferred from different genes were poorly resolved but suggest that the species with a moniliform macronucleus comprise an early-diverging clade within this genus.Finally,the global distribution of Spirostomum is summarized based on previous and present studies.

关 键 词：CONJUGATION MORPHOGENESIS Morphology PHYLOGENY Ribosomal RNA 

分 类 号：Q95[生物学—动物学]