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Difficulties encountered previously in separating the cocoons and some juveniles of Hirudo medicinalis and Haemopis sanguisuga have been resolved by the present study. The cocoons of Hirudo medicinalis are larger and have a different structure from those of Haemopis sanguisuga. Some of the darker juveniles of Haemopis sanguisuga may be confused with those of Hirudo medicinalis, but can be separated by careful examination of both dorsal and ventral colour patterns.  相似文献   
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利用Illumina和Pacbio测序技术对扬子鳃蛭(Ozobranchus jantseanus)线粒体基因组全序列进行测序及注释,并与NCBI数据库中蛭纲(Hirudinea)其他物种的线粒体全序列的排列方式和系统进化关系进行了比较,以确定其系统学地位.结果显示:获得的线粒体基因组序列长度为14 868 bp,蛋白编码基因存在2种起始密码子,分别为ATG和ATT;终止密码子共有4种,分别为TAA,TAG,TA和T;蛭纲10个物种的线粒体基因组全序列基因排序可分为2种类型,其差异表现在tRNAs的互换和长非编码区的长度的不同;扬子鳃蛭所属的吻蛭目(Rhynchobdellida)均为b型,绝大部分无吻蛭目(Arhynchobdellida)的排列方式为a型.基于蛭纲物种的13个蛋白编码基因(PCGs)的Neighbor-Joining(NJ)树进化分析显示,扬子鳃蛭与其他吻蛭目物种聚类.  相似文献   
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Historically, there has been much confusion surrounding the identity and separation of European and North American species of Glossiphonia (Annelida: Clitellata: Glossiphoniidae). Using cytochrome c oxidase subunit I (COI) sequences from newly collected specimens of Glossiphonia complanata and Glossiphonia elegans from a broad geographic range covering southern Canada, parts of the US, Slovenia and Croatia, we confirm that G. complanata is likely confined to Europe. The species is phylogenetically distinct from G. elegans, which seems to exclusively inhabit North America. Parsimony and maximum likelihood of the COI locus show the European samples placing as the sister group to an unidentified species of Glossiphonia from Russia, while the North American samples are the sister group to all other Glossiphonia species. We also investigate the consistency of number of crop cecae for separating these species and contrary to previous reports, this character shows no differences between our specimens of the two species. Additionally, the trees show evidence of subdivisions within both G. complanata and G. elegans, with some sequences separated by high ‘intraspecific’ distances. Forces might be shaping population structure and/or potential incipient speciation within these species, emphasizing the need for future research into the biogeography and population genetics of Glossiphonia.  相似文献   
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利用Illumina和Pacbio测序技术对扬子鳃蛭(Ozobranchus jantseanus)线粒体基因组全序列进行测序及注释,并与NCBI数据库中蛭纲(Hirudinea)其他物种的线粒体全序列的排列方式和系统进化关系进行了比较,以确定其系统学地位.结果显示:获得的线粒体基因组序列长度为14 868 bp,蛋白编码基因存在2种起始密码子,分别为ATG和ATT;终止密码子共有4种,分别为TAA,TAG,TA和T;蛭纲10个物种的线粒体基因组全序列基因排序可分为2种类型,其差异表现在tRNAs的互换和长非编码区的长度的不同;扬子鳃蛭所属的吻蛭目(Rhynchobdellida)均为b型,绝大部分无吻蛭目(Arhynchobdellida)的排列方式为a型.基于蛭纲物种的13个蛋白编码基因(PCGs)的Neighbor-Joining(NJ)树进化分析显示,扬子鳃蛭与其他吻蛭目物种聚类.  相似文献   
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