基于18S rRNA基因部分序列探讨四种蛙类多盘科吸虫分类地位

THE TAXONOMIC STATUS OF FOUR ANURAN POLYSTOMATIDS(MONOGENEA,POLYSTOMATIDAE)ASSESSED BY PARTIAL SEQUENCES OF 18S rRNA GENE

分析了寄生于蛙类膀胱的4种多盘虫科Polystomatidae吸虫:石林双睾吸虫Diplorchis shilinensis、锯腿树蛙多盘吸虫Polystoma carvirostris和分别寄生于昭觉林蛙Rana chaochiaoensis、华西雨蛙Hyla a.annectans的2未定种的分类地位,并利用18S rRNA基因部分序列进行了系统发育重建。结果表明:4种多盘科吸虫为多盘虫属Polystoma和双睾虫属Diplorchis的4个分类单元,其中2未定种为多盘虫属未记录种;肠管、生殖系统、后吸器、大钩和生殖棘等为多盘虫属属内种定种的可靠性状。基于18S rRNA基因序列,4种多盘科吸虫呈现以下进化关系:1)寄生于昭觉林蛙和华西雨蛙的多盘虫属2未定种进入欧非混合进化支;2)锯腿树蛙多盘吸虫位于多盘虫属进化支的最基部;3)石林双睾吸虫进入澳洲进化支。

The taxonomic status of 4 polystomatids within the family Polystomatidae from Yunnan Province was evaluated. The phylogeny was reconstructed and assessed by partial sequences of 18S rRNA gene. The specimens include Polystoma carvirostris, Diplorchis shilinensis and 2 polystomatids which firstly discovered from urinary bladder of hosts Rana chaochiaoensis and Hyla a. annectans respectively. The parasites exclusively belonged to four taxa of genus Polystoma and genus Diplorchis. Polystomatids parasitic in hosts R. chaochiaoensis and H. a. annectans were suggested as 2 different taxon of genus Polystoma awaited scientific description. The results indicated that morphological characteristics such as variation in gut arrangement, reproductive system, haptro, hamuli and amount of genital spine are dependable traits for distinguish different taxa in genus Polystoma. The phylogeny relationships between these 4 polystomatids were presented below： 1） Polystoma sp. parasitic in host R. chaochiaoensis and H. annectans belonged to Eurafrican clade; 2） P. carvirostris located basally in the clade of genus Polystoma; 3） D. shilinensis belonged to Australia clade.