南黄海潮间带海洋线虫多样性及中国海4个新纪录种记述

Diversity of marine nematodes and the descriptions of four new record species from the intertidal zone of the Southern Yellow Sea

为了查清南黄海自由生活海洋线虫(Nematoda)种类组成和物种多样性,作者开展了南黄海沿岸潮间带自由生活海洋线虫的分类和多样性研究。通过形态学分类方法鉴定出海洋线虫247种或分类实体,其中最优势属为吞咽线虫属(Daptonema),属内个体占线虫总数的19.6%,次之为近色矛线虫属(Chromadorina)、折咽线虫属(Ptycholaimellus)和棘刺线虫属(Theristus)。最优势种为暹罗海单宫线虫(Thalassomonhystera siamensis Kito&Aryuthaka,1998),数量上占线虫总数的12.6%,其次为拟短毛吞咽线虫(Daptonema parabreviseta Huang&Sun,2018)和眼点折咽线虫(Ptycholaimellus ocellus Huang&Wang,2011)等。描述并图示了中国4个海洋线虫新纪录种,即居中嘴咽线虫(Enoplolaimus medius Pavljuk,1984)、暹罗海单宫线虫(Thalassomonhystera siamensis Kito&Aryuthaka,1998)、韦伯斯特绒毛线虫(Pomponema websteri Sharma&Vincx,1982)和条纹隆唇线虫(Xyala striata Cobb,1920),进一步了解了这4个物种的地理分布区。隆唇线虫属(Xyala)是中国海域的首次报道,为中国线虫多样性增加了新属的纪录,同时丰富了中国海洋线虫的物种多样性信息。南黄海沿岸潮间带8个采样站位海洋线虫香农-威纳多样性指数(H′)为1.859~3.022,小于南黄海潮下带的多样性指数2.56~3.79,因此南黄海潮间带线虫的多样性低于潮下带线虫多样性。

In February 2021,samples were collected from the intertidal zone along the coast of the Yellow Sea(31°4′-35°6′N,119°1′-121°6′E).Classification and biodiversity of the free-living nematodes in the samples were researched.A total of 247 species or taxa of free-living nematodes belonging to 104 genera,32 families,and 9 orders were identified,among which Daptonema was identified as the most dominant genus,followed by Chromadorina,Ptycholaimellus,and Theristus.The most dominant species was Thalassomonhystera siamensis Kito&Aryuthaka,1998,accounting for 12.6%of the total nematodes,followed by Daptonema parabreviseta Huang&Sun,2018,and Ptycholaimellus ocellus Huang&Wang,2011,respectively.Four new records of free-living marine nematodes in China have been described and illustrated herein,including Enoplolaimus medius Pavljuk,1984,T.siamensis Kito&Aryuthaka,1998,Pomponema websteri Sharma&Vincx,1982,and Xyala striata Cobb,1920.Xyala was reported for the first time in China seas.The distribution scope of these four species would broaden and enrich the biodiversity information about the free-living marine nematodes in China.Across eight sampling stations from the intertidal zone of the southern Yellow Sea,the Shannon-Wiener diversity index of marine nematodes was 1.859-3.022,which is less than that of the subtidal zone(2.56-3.79).This finding indicated that the diversity of nematodes in the intertidal zone of the Southern Yellow Sea was lower than that in the subtidal zone.