Will Watson / Smooth newt (Lissotriton vulgaris) female with two leeches (Helobdella stagnalis) Hereford City pond, Herefordshire, England, UK, April. Captive.

Nick Upton / Duck Leech (Theromyzon tessulatum) waiting and ready to crawl up the nostrils of a duck to suck blood from its respiratory tracts, reaching out from a Delicate stonewort (Chara virgata) alga in a shal...