American Society of Hirudotherapy

Segmented worms (Phylum Annelida): a celebration of twenty years of progress through Zootaxa and call for action on the taxonomic work that remains

Research article published in Zootaxa (2021)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Clinical TrialsMagalhes et al. · Zootaxa, 2021

Abstract

Zootaxa has been the leading journal on invertebrate systematics especially within Annelida. Our current estimates indicate annelids include approximately 20,200 valid species of polychaetes, oligochaetes, leeches, sipunculans and echiurans. We include herein the impact of Zootaxa on the description of new annelid species in the last two decades. Since 2001, there have been over 1,300 new annelid taxa published in about 630 papers. The majority of these are polychaetes (921 new species and 40 new genera) followed by oligochaetes (308 new species and 10 new genera) and leeches (21 new species). The numerous papers dealing with new polychaete species have provided us a clear picture on which polychaete families have had the most taxonomic effort and which authors and countries have been the most prolific of descriptions of new taxa. An estimated additional 10,000+ species remain to be described in the phylum, thus we urge annelid workers to continue their efforts and aid in training a new generation of taxonomists focused on this ecologically important group.

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

Publication typeJournal Article
Indexed MeSH termsAnimalsAnnelidaPeriodicals as TopicPhylogeny

Summary

Peer-reviewed clinical and outcomes research relevant to anticoagulation, leech therapy, and microsurgical flap management. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This is a taxonomic review of the phylum Annelida, summarizing two decades of new-species descriptions in the journal Zootaxa; per the abstract it counts roughly 20,200 valid annelid species and notes that only 21 new leech species were described since 2001, with the bulk of the work on polychaetes and oligochaetes, and an estimated 10,000+ species still undescribed. NAMING/SCOPE NOTE: 'leeches' here appear only as one taxonomic subgroup within annelid biodiversity accounting — this paper is about systematics and the need to train more taxonomists, not about the medicinal leech (Hirudo medicinalis) or its salivary pharmacology. It has no direct bearing on hirudotherapy, the leech secretome, or clinical anticoagulation evidence, and should be read as background biodiversity context only.

Citation

Segmented worms (Phylum Annelida): a celebration of twenty years of progress through Zootaxa and call for action on the taxonomic work that remains.

Magalhes et al. · Zootaxa, 2021

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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