湘西峒河流域星齿蛉幼虫分子鉴定与体表呼吸结构观察

星齿蛉属Protohermes隶属于广翅目Megaloptera齿蛉科Corydalidae,是一类原始的完全变态昆虫,幼虫水生,常作为指示生物用于水质监测。本文对湘西峒河流域两种星齿蛉幼虫进行了分子鉴定和体表呼吸结构观测。结果表明两种星齿蛉幼虫COⅠ基因序列分别与花边星齿蛉Protohermes costalis和炎黄星齿蛉Protohermes xanthodes同源性较高;遗传距离分析和系统发育分析进一步证实两种星齿蛉幼虫分别属于花边星齿蛉和炎黄星齿蛉,分子鉴定结果与成虫形态鉴定结果一致。花边星齿蛉和炎黄星齿蛉幼虫体表呼吸结构气门、毛簇、气管鳃和臀足侧突均与气管相连,毛簇是主要的水下呼吸结构。本研究结果为峒河流域星齿蛉昆虫资源的保护和开发利用提供了科学数据。

Molecular identification of Protohermes larvae in Donghe River basin and observation of the surface respiratory structures

Species of Protohermes(Megaloptera,Corydalidae)are holometabolous insects.Their larvae are aquatic and are widely used as indicators of water quality.In this study,Protohermes larvae collected from Donghe River basin were identified based on COⅠgene sequence.The cloned COⅠgene sequences share high identities with that of Protohermes costalis and Protohermes xanthodes,respectively.Genetic distance analysis and phylogenetic analysis further confirmed that the collected larvae are P.costalis and P.xanthodes.The surface respiratory structures(spiracles,tracheal gill tufts,tracheal gills and proleg lateral lobe)of P.costalis and P.xanthodes larvae are linked with the trachea,and the tracheal gill tufts are the main structures for respiration in water.These findings provide basis for conservation and exploitation of Protohermes larvae in Donghe River basin.