Detail of an Olm or Proteus {Proteus anguinus} showing the three-toed front limb and gills. This species is a true troglobite (living only in caves) and is highly adapted to the cave environment. They generally lack any skin pigmentation and are blind, with atrophied eyes. They have advanced senses of taste, touch and smell as well as being able to detect weak electrical fields, allowing them to navigate the cave environment and locate their prey. They exhibit neoteny, meaning they retain larval characteristics into adulthood such as gills. Captive, Slovenia.