Proteus-eggs were found for the first time in the nature, drifted out of a karstic spring. They were obtained from the Vir Spring al Sticna, 30 km ESE of Ljubljana. The hydrological and faunistical data indicate that Proteus lays its eggs also in “unsheltered”, energetically rich groundwater habitats.
Sket, B. and F. Velkovrh.
The Discovery of Proteus-eggs (Proteus anguinus Laurenti, Amphibia) in Seminatural Conditions.
International Journal of Speleology,
Available at: https://scholarcommons.usf.edu/ijs/vol10/iss2/7