Underground and unknown: Updated distribution, ecological notes and conservation guidelines on the olm proteus anguinus anguinus in Italy (amphibia, proteidae)

Abstract

Proteus anguinus reaches the extreme western border of its distribution in Venezia Giulia, a narrow area of Italian territory in the provinces of Trieste and Gorizia. An alien population of P. anguinus is nowadays well acclimatised near Oliero Valstagna (Vicenza). The ancestors of diis population were introduced from Postojna (Slovenia) and could therefore be genetically well distinct from the Italian ones in Venezia Giulia. Proteus anguinus is autochthonous in 26 different localities from the Carso Triestino plateau, were it inhabits hypogeal aquifers situated around sea level, but sometimes more than 300 m under the ground level of the karstic plateau. Specimens that occur in springs, pools or wells in big caves near the surface, seem to do so only to feed. Eggs, larvae, breeding and territorial behaviour have never been observed in nature. Further studies need to be addressed to better understand ecology and genetic characterisation of P. anguinus, focusing mainly on the naturalised population of Valstagna and on the olms naturally occurring under the village of Gradisca. Conservation efforts need to be made to maintain P. anguinus habitats, stopping aquifer pollution and regulating caves and karst exploitation. © 2004 Taylor & Francis Group, LLC.