Medicinal leech  (Hirudo medicinalis)

Species information

Videos and images

Information supplied by English Nature:

http://www.englishnature.org.uk/

Amphibian: a cold-blooded vertebrate of the class Amphibia, such as a frog or salamander, that characteristically hatches as an aquatic larva with gills. The larva then transforms into an adult having air-breathing lungs.
Amphibious: capable of living both on land and in water.