Fish Leech - Piscicola geometra


25 to 50 mm long, with a segmented, cylindrical body that has suckers at either end, enabling it to attach to fish for feeding. It can attach to the body, gills or mouth where it feeds on blood, then drops off when satiated. They can swim strongly in a whip-like motion. The eye pattern on the anterior sucker is usually characteristic.

Similar Species

There are two UK species of Piscicola, P. geometra is cyclindrical whereas P. siddali is flattened dorso-ventrally.

Identification difficulty
Recording advice

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Occurs in marine, brackish and freshwater, including garden ponds.

When to see it

All year round.

Life History

Feeds on fish by attaching itself whilst feeding on blood, then detaching and hiding amongst stones or plants.

UK Status

Piscicola geometra is the most common fish leech found in garden ponds. 

VC55 Status

Status in Leicestershire and Rutland unknown.

Leicestershire & Rutland Map


Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015

UK Map

Species profile

Common names
fish leech
Species group:
Records on NatureSpot:
First record:
04/04/2023 (Nicholls, David)
Last record:
07/04/2023 (Nicholls, David)

Total records by month

% of records within its species group

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