Internal and External Morphological Characteristics of the Medicinal Leech Species
Research article published in Turkiye parazitolojii dergisi (2019)
Abstract
OBJECTIVE: The aim of this study was to investigate the internal and external morphological structures of two species of medicinal leeches (Hirudo sulukii and Hirudo verbana). METHODS: Leech specimens were collected from various regions of Turkey between the years of 1995-2016. The leeches were first examined alive and later were stunned with 10% ethyl alcohol and fixed in 70% ethyl alcohol or 4% formaldehyde. After fixation, the internal morphology of leeches was examined by dissecting them under a stereo microscope. RESULTS: Both species of leeches are dorso-ventrally flattened. H. verbana is larger and broader than H. sulukii. H. sulukii has black, segmentally-arranged united ellipsoid and elongated spots, and a pair of zigzagged black longitudinal stripes in the dorso-lateral area of its body. The ventral surface of H. sulukii is greenish to brown in colour and has a small number of irregular black spots. H. verbana has broad and diffuse, paramedian, orange stripes on the dorsal surface. Ventrally, H. verbana has a greenish to yellow colour, and it is characterized by a pair of black ventro-lateral stripes. CONCLUSION: Two of the six leech species (Hirudo sulukii and Hirudo verbana) belonging to the genus Hirudo found in the world are found in Turkey. These two leech species show significant differences from each other, morphologically.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
The aim of this study was to investigate the internal and external morphological structures of two species of medicinal leeches ( Leech specimens were collected from various regions of Turkey between the years of 1995-2016.
Why This Matters for Hirudotherapy
The study examined the internal and external morphological structures of two medicinal leech species, Hirudo sulukii and Hirudo verbana, collected from regions of Turkey between 1995 and 2016, using stereo microscopic dissection after fixation. Accurate species-level identification is relevant to hirudotherapy because it underpins reliable sourcing and correct taxonomic classification of medicinal leeches; the detailed descriptions—such as H. verbana being larger with broad orange dorsal stripes versus H. sulukii's segmental black spots and zigzagged longitudinal stripes—provide distinguishing features for identification. However, the study is strictly morphological in scope, reporting anatomical and external characteristics without investigating salivary secretions, bioactive components, clinical effects, or any therapeutic properties. Its relevance to ASH's domain is therefore limited to species identification rather than providing mechanistic or clinical insight into hirudotherapy.
Citation
Internal and External Morphological Characteristics of the Medicinal Leech Species
Sağlam N · Turkiye parazitolojii dergisi, 2019
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