# Medicinal leech (*Hirudo medicinalis*)

Canonical page: https://creaturedata.com/animals/medicinal-leech  
Data as of: 2026-11-14

The medicinal leech (Hirudo medicinalis) is a worm in the family Hirudinidae, part of the order Arhynchobdellida and the class Clitellata. It belongs to the phylum Annelida and was named by Linnaeus, 1758. The medicinal leech is listed as Near Threatened in the global IUCN Red List assessment, which is not an IUCN threatened category.

## Quick facts

| Fact | Value |
|---|---|
| Weight | Not recorded |
| Length | up to 20 cm |
| Lifespan | Not recorded |
| Main food | Not recorded |
| Habitat | freshwater |
| Young per litter or clutch | Not recorded |
| Reproduction | Eggs |
| Conservation status | Near Threatened (IUCN) |
| Countries on record | Not recorded |

## Introduced range

The Global Register of Introduced and Invasive Species lists it as introduced in 2 countries. Introduced: Denmark, United States. Source: https://griis.org/ (CC BY 4.0).

## Classification

- kingdom: Animalia
- phylum: Annelida
- class: Clitellata
- order: Arhynchobdellida
- family: Hirudinidae
- genus: Hirudo
- species: *Hirudo medicinalis* Linnaeus, 1758

Synonyms: *Sanguisuga medicinalis*

## Common questions

### What is the scientific name of the medicinal leech?

The scientific name of the medicinal leech is Hirudo medicinalis. It is placed in the genus Hirudo.

### Who named the medicinal leech and when?

The medicinal leech was named by Linnaeus, 1758.

### Is the medicinal leech endangered?

No, the medicinal leech is listed as Near Threatened in the global IUCN Red List assessment. This is not an IUCN threatened category.

### What other names does the medicinal leech have?

The medicinal leech is also called the European medicinal leech and the European blood-sucking leech.

### What family and order does the medicinal leech belong to?

The medicinal leech belongs to the family Hirudinidae and the order Arhynchobdellida, within the class Clitellata.

### Is the medicinal leech an invasive species?

The Global Register of Introduced and Invasive Species lists the medicinal leech as introduced in 2 countries: Denmark and United States, but does not flag it as invasive in any of them.

## Sources

- [Catalogue of Life eXtended Release](https://www.checklistbank.org/dataset/316691), CC BY 4.0, 2026-10-16 XR. Catalogue of Life (2026). Catalogue of Life eXtended Release, version 2026-10-16 XR. Catalogue of Life Foundation, Amsterdam, Netherlands. https://doi.org/10.48580/dgzlf
- [Wikimedia Commons](https://commons.wikimedia.org), per file (CC0 / public domain / CC BY green, CC BY-SA amber, anything else not displayed), 2026-11-11. Wikimedia Commons contributors. Wikimedia Commons. https://commons.wikimedia.org (each file credited to its author under its own licence).
- [Global Register of Introduced and Invasive Species (GRIIS)](https://griis.org/), CC BY 4.0, 2026-11-13. Pagad, S., Genovesi, P., Carnevali, L., Schigel, D. & McGeoch, M.A. (2018) Introducing the Global Register of Introduced and Invasive Species. Scientific Data 5: 170202. https://doi.org/10.1038/sdata.2017.202. Country checklists published through GBIF by the IUCN SSC Invasive Species Specialist Group.
- [Wikidata](https://www.wikidata.org), CC0 1.0, 2026-11-11. Wikidata contributors. Wikidata. https://www.wikidata.org (data retrieved via the Wikidata Query Service).
- [Wikipedia (English)](https://en.wikipedia.org), CC BY-SA 4.0, 2026-11-11. Wikipedia contributors. Wikipedia, The Free Encyclopedia. https://en.wikipedia.org (text under CC BY-SA 4.0; each block names its article and revision).

Cite as: Medicinal leech (Hirudo medicinalis). Retrieved from https://creaturedata.com/animals/medicinal-leech