The Olm - Proteus anguinus
This strange creature is commonly known as the Olm, a rare cave salamander belonging to the species Proteus anguinus (Caudata - Proteidae), which is only found in Europe.
The Olm is perfectly adapted to live in caves. As it spends its entire life in darkness, Proteus anguinus has very poorly developed eyes and is blind. It also lacks pigment in the skin, giving its body a pasty white appearance, Its pink hue is due to blood capillaries near the skin, and as its translucency shows the contours of the internal organs.
This salamander does not undergo a clear metamorphosis and retains many juvenile features, such as gills, throughout its life. It is long-lived, potentially reaching up to 58 years of age.
The Olm is restricted to subterranean aquatic habitats in Bosnia and Herzegovina, Croatia, France, Italy and Slovenia. The species is classified as Vulnerable on the IUCN Red List.
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Photo credit: [Top: ©Darko Visek | Locality: Rokina, Croatia, 2008] - [Bottom: ©National Geographic | Locality: Divje Jezero, Idrija, Slovenia]