Department of Biology, Biotechnical Faculty, University of Ljubljana, P.O. Box 2995, SI-1001 Ljubljana, Slovenia.
Mol Phylogenet Evol. 2012 May;63(2):475-85. doi: 10.1016/j.ympev.2012.01.022. Epub 2012 Feb 8.
Medicinal leeches (Hirudo spp.) are among the best-studied invertebrates in many aspects of their biology. Yet, relatively little is known about their biogeography, ecology and evolution. Previous studies found vast ranges but suggested low genetic diversity for some species. To examine this apparent contradiction, the phylogeny and phylogeography of the widespread Hirudo verbana, Hirudo medicinalis and Hirudo orientalis were investigated in a comparative manner. Populations from across their ranges in Europe, Asia Minor, the Caucasus and Central Asia, were analyzed by various phylogenetic and population genetic approaches using both mitochondrial (COI and 12S) and nuclear DNA sequences (ITS1, 5.8S and ITS2). The populations showed surprisingly little genetic differentiation despite vast ranges. The only clear structure was observed in H. verbana. This species is subdivided into an Eastern (southern Ukraine, North Caucasus, Turkey and Uzbekistan) and a Western phylogroup (Balkans and Italy). The two phylogroups do not overlap, suggesting distinct postglacial colonization from separate refugia. Leeches supplied by commercial facilities belong to the Eastern phylogroup of H. verbana; they originate from Turkey and the Krasnodar Territory in Russia, two leading areas of leech export. H. verbana and H. medicinalis have experienced recent rapid population growth and range expansion, while isolation by distance has shaped the genetic setup of H. orientalis. The habitat of the latter is patchy and scattered about inhospitable arid and alpine areas of Central Asia and Transcaucasia. Centuries of leech collecting and transport across Europe seem not to have affected the natural distribution of genetic diversity, as the observed patterns can be explained by a combination of historical factors and present day climatic influences.
医用水蛭（ Hirudo spp. ）在其生物学的许多方面都是研究最多的无脊椎动物之一。然而，关于它们的生物地理学、生态学和进化，人们知之甚少。先前的研究发现了广泛的范围，但表明一些物种的遗传多样性较低。为了研究这种明显的矛盾，采用比较的方法研究了分布广泛的医用水蛭 Hirudo verbana 、 Hirudo medicinalis 和 Hirudo orientalis 的系统发育和系统地理学。通过各种系统发育和种群遗传方法，使用线粒体（COI 和 12S）和核 DNA 序列（ITS1、5.8S 和 ITS2）对来自欧洲、小亚细亚、高加索和中亚各地的种群进行了分析。尽管分布范围很广，但这些种群的遗传分化很小。仅在 Hirudo verbana 中观察到明显的结构。该物种分为东部（乌克兰南部、北高加索、土耳其和乌兹别克斯坦）和西部谱系群（巴尔干半岛和意大利）。这两个谱系群不重叠，表明在不同的冰河期后从不同的避难所进行了明显的殖民化。商业设施提供的医用水蛭属于 Hirudo verbana 的东部谱系群；它们原产于土耳其和俄罗斯克拉斯诺达尔地区，这两个是医用水蛭出口的主要地区。Hirudo verbana 和 Hirudo medicinalis 经历了近期的快速种群增长和范围扩张，而距离隔离塑造了 Hirudo orientalis 的遗传结构。后者的栖息地是分散的，分布在中亚和外高加索干旱和高山地区。几个世纪以来，医用水蛭在欧洲的收集和运输似乎并没有影响遗传多样性的自然分布，因为观察到的模式可以通过历史因素和当前气候影响的组合来解释。
