Fèlix Amat; Neus Oromí; Delfí Sanuy and Salvador Carranza. Amphibia-Reptilia. Volume 36, Issue 3. Patterns of sexual dimorphism and age structure were investigated in two populations of the newt Calotriton arnoldi, endemic of the Montseny Massif (NE of the Iberian Peninsula). In contrast to the Pyrenean newt ( Calotriton asper) sexual dimorphism in the Montseny brook newt is characterized by slightly larger females (60.3 ± 0.3 mm; maximum: 68 mm) than males (59.5 ± 0.2 mm; maximum: 64 mm) and more similar body shape between sexes. Both populations and sexes mature at the same age (3 years), show the same age structure and achieve similar longevity (8-9 years). Leer más.