Olm
Olms are the nine species in the genus Proteus. They are aquatic salamanders, and the only exclusively cave-dwelling chordate genus found in Europe. The genus is assigned to the family Proteidae, along with Necturus. In contrast to most amphibians, this genus is entirely aquatic; eating, sleeping, and breeding underwater. Living in caves found in the Dinaric Alps, the genus is endemic to the waters that flow underground through the extensive limestone bedrock of the karst of Central and Southeastern Europe in the basin of the Soča River near Trieste, Italy, southern Slovenia, southwestern Croatia, and Bosnia and Herzegovina. Introduced populations are found near Vicenza, Italy, and Kranj, Slovenia. It was first mentioned in 1689 by the local naturalist Valvasor in his Glory of the Duchy of Carniola, who reported that, after heavy rains, the olms were washed up from the underground waters and were believed by local people to be a cave dragon's offspring.
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