Nesting of cave salamanders (Hydromantes flavus and H. italicus) under natural conditions

The reproductive biology of European salamanders of the genus Hydromantes (subgenus Speleomantes) is poorly known. The lack of information is related to their cryptic behaviour and habitat, which make detection extremely difficult, especially during breeding-related activities. Most of the information on Hydromantes reproduction refers to observations in captivity and in semi-natural conditions, while observations in the wild are extremely limited. We report on the first observations of brooding and maternal care in Hydromantes italicus and H. flavus in natural environments. In both species, brooding females and eggs were found in small fissures within the aphotic zone of caves where microclimates are stable. After hatching, the females of both species attended continuously to their newborns. Available information on breeding biology suggests high similarity amongst species, but more studies, under both natural and controlled conditions, are required to better understand the complex breeding behaviour of Hydromantes salamanders and evaluate interspecific variation.