American Society of Hirudotherapy

Taxonomic update and DNA barcoding of Tunisian nasal leeches: confirming Limnatis nilotica and revealing a second species

Taxonomy study published in Invertebrate Systematics (2025)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Genomics & ProteomicsSafety & Infection ControlBen Ahmed R et al. · Invertebrate systematics, 2025

Abstract

Leeches of the genus Limnatis are known ectoparasites of vertebrates, including humans and domestic animals, with some species causing significant health complications. In this study, we describe Limnatis anouarensis sp. nov., a new nasal leech species from Tunisia and compare it with Limnatis nilotica sensu stricto from Tunisia and Morocco. Morphological analyses were conducted using light and scanning electron microscopy, focusing on external and internal structures. Additionally, mitochondrial (cytochrome c oxidase subunit I, COI; 12S rRNA, 12S) and nuclear (28S rRNA, 28S) gene fragments were sequenced for molecular characterisation. The new species is distinguished by its larger size, distinct reproductive system morphology and unique dorsal colouration, characterised by a median orange band and marginal orange stripes, in contrast to the black-striped pattern of L. nilotica (Moore, 1938). Molecular analyses confirmed that mitochondrial markers provide reliable species identification, whereas the analysed fragment of 28S gene was fully conserved and unsuitable for differentiation. These findings confirm the presence of at least two distinct Limnatis species in North Africa, emphasising the need for further taxonomic and ecological studies to clarify their distribution, host specificity and potential medical significance. ZooBank: urn:lsid:zoobank.org:pub:7CA59D0E-1D42-4A02-B886-D198DD88E698.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article
Indexed MeSH termsAnimalsDNA Barcoding, TaxonomicLeechesTunisiaSpecies SpecificityPhylogenyAfrica, NorthernElectron Transport Complex IVRNA, Ribosomal, 28S

Summary

Confirms Limnatis nilotica (nasal leech parasite of mammals including humans) as widespread in Tunisia and identifies a second cryptic Limnatis species via DNA barcoding.

Why This Matters for Hirudotherapy

This study describes Limnatis anouarensis sp. nov., a new nasal leech species from Tunisia, and compares it morphologically and molecularly with Limnatis nilotica sensu stricto from Tunisia and Morocco. The new species is distinguished by larger size, distinct reproductive system morphology, and unique dorsal coloration (median orange band and marginal orange stripes vs. the black-striped pattern of L. nilotica). Mitochondrial markers (COI, 12S) reliably differentiated the species, while the 28S fragment was conserved and unsuitable. For ASH, this is relevant because Limnatis leeches are ectoparasites of vertebrates including humans and can cause health complications, and the study notes the need to clarify their distribution and medical significance. However, the work itself is taxonomic and does not investigate anticoagulants, the secretome, hirudotherapy, or therapeutic applications of leeches.

Citation

Taxonomic update and DNA barcoding of Tunisian nasal leeches: confirming Limnatis nilotica and revealing a second species.

Ben Ahmed R et al. · Invertebrate systematics, 2025

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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