species 245 observations
Duck Leech
Theromyzon tessulatum
Field notes
Theromyzon tessulatum is a species of leech in the family Glossiphoniidae. It is a haematophagous (blood-sucking) leech, found in freshwater habitats in Europe.
Read more on WikipediaRange
Greener is more native, amber more introduced; paler is less certain. How this was decided