Celebrity with a neglected taxonomy: molecular systematics of the medicinal leech (genus Hirudo)
Phylogenetics article published in Molecular Phylogenetics and Evolution (2004)
Abstract
The medicinal leech is the most famous representative of the Hirudinea. It is one of few invertebrates widely used in medicine and as a scientific model object. It has recently been given considerable conservation effort. Despite all attention there is confusion regarding the taxonomic status of different morphological forms, with many different species described in the past, but only two generally accepted at present. The results of the phylogenetic analysis of a nuclear (ITS2+5.8S rRNA) and two mitochondrial gene sequences (12S rRNA, COI) suggest that the genus Hirudo is monophyletic. It consists, apart form the type Hirudo medicinalis and the East Asian Hirudo nipponia, of three other, neglected species. All of them have already been described either as species or morphological variety, and can readily be identified by their coloration pattern. The type species is in weakly supported sister relation with Hirudo sp. n. (described as variety orientalis) from Transcaucasia and Iran. Sister to them stands Hirudo verbana from southeastern Europe and Turkey, which is nowadays predominantly bred in leech farms and used as 'medicinal leech.' The North African Hirudo troctina is the sister taxon to this group of Western Eurasian species, whereas the basal split is between H. nipponia and the Western Palaearctic clade.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Molecular phylogenetic analysis (ITS2+5.8S rRNA, 12S rRNA, COI) demonstrates Hirudo genus monophyly and three previously neglected species (H. verbana, H. orientalis, H. troctina) alongside H. medicinalis and H. nipponia.
Why This Matters for Hirudotherapy
Corrects long-standing taxonomic confusion about which Hirudo species is actually used clinically.
Citation
Celebrity with a neglected taxonomy: molecular systematics of the medicinal leech (genus Hirudo).
Trontelj P, Utevsky SY · Molecular phylogenetics and evolution, 2004
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