浙江洞头岛自由生活线虫两个优势种的形态描述及其系统发育分析  

Morphological descriptions and phylogenetic analysis of two dominant species of free-living marine nematodes in Dongtou Island,Zhejiang

作　　者：郭文 梁慧鑫 吕艳伟[1] 王春明[1] GUO Wen;LIANG Huixin;LV Yanwei;WANG Chunming(College of Life Sciences,Liaocheng University,Liaocheng 252059,China)

机构地区：[1]聊城大学生命科学学院,山东聊城252059

出　　处：《海洋科学》2024年第4期45-52,共8页Marine Sciences

基　　金：国家自然科学基金项目(31100456)。

摘　　要：为了了解浙江洞头岛自由生活线虫(Nematoda)的种类和多样性,作者对该海域线虫进行分类研究,发现了2个优势种并进行了重新描述。其中,丑萨巴线虫(Sabatieria foetida Gagarin&Nguyen Vu Thanh,2008)为一新纪录种,主要特征为:表皮具环状排列的小点,有较大的点组成的侧装饰,4根头刚毛较短(3~4μm),化感器呈螺旋状(2.5~3.0圈),交接刺细长,近端略膨大,中间开始至远端变细(65~69μm),引带具直的引带突(20~25μm),具13~15个小的乳突状肛前辅器;厦门后菱光线虫(Metachromadora xiamenensis Zhou,Zeng,Cai,Fu&Tan,2020)特征为:表皮具明显环纹,4根头刚毛短且粗,脊线由食道中部延伸至尾中部,双环状化感器位于身体最前端,交接刺近端具头状膨大(58~65μm),肛前辅器细管状(15个),尾为短圆锥形。同时,获得了两种线虫核糖体大亚基(LSU)的D2-D3片段序列数据,构建了两种线虫基于贝叶斯推论法(Bayesian inference,BI)和最大似然法(maximum likelihood,ML)的系统发育树,结果表明萨巴线虫属和后菱光线虫属表现出了多系进化的趋势。Two dominant species,Sabatieria foetida Gagarin&Nguyen Vu Thanh,2008 and Metachromadora xiamenensis Zhou,Zeng,Cai,Fu,&Tan,2020,were redescribed during the classification and diversity studies of free-living marine nematodes in Dongtou Island,Zhejiang Province.S.foetida was first described as a recorded species and characterized by a cuticle with small punctuations and lateral differentiation with large dots,four short cephalic setae(3-4μm in length),spiral-shaped amphidial fovea(2.5-3.0 turns),curved spicules with proximal ends that are cephalate and slender from the middle part,gubernaculum with straight apophysis(20-25μm in length),and 13-15 papilliform precloacal supplements.Furthermore,M.xiamenensis is characterized by a coarsely striated cuticle with lateral alae starting from the middle pharynx to the tail,four short and stout cephalic setae,amphids with a double contour at the anterior end,spicules with a cephalated proximal end(58-65μm in length),15 tubular precloacal supplements,and a short and conical tail.The D2-D3 fragments of the LSU rDNA of S.foetida and M.xiamenensis were amplified and sequenced.Moreover,phylogenetic trees based on Bayesian inference and maximum likelihood revealed polyphyletic evolution in the genera Sabatieria and Metachromadora.

关 键 词：丑萨巴线虫(Sabatieria foetida) 厦门后菱光线虫(Metachromadora xiamenensis) LSU 系统发育 

分 类 号：Q19[生物学—普通生物学]