洞螈

• European proteus cannot breathe only with lungs and dies within several hours if removed from water. Despite having lungs, it needs water to breathe.
• European proteus is a neotenic form of an ancient salamander, like the axolotl. It is believed that this feature is retained in it, unlike other members of its species.
• European proteus lives on average 69 years, and some individuals reach over 100 years of age. The maximum recorded lifespan in nature is 102 years, a record for amphibians.
• European proteus can survive without food for many months. In a year, it rarely travels more than 10 meters.
• External gills are retained by the European proteus throughout its life. The animal has small legs.
• European proteus lives in underground lakes on the western part of the Balkan Peninsula. The amphibian has earned the nickname "human fish" due to the similarity of its color to human skin.