Fatal heterospecific amplexus of Rana temporaria on Salamandra salamandra in a small artificial breeding site in the Lombardy Pre-Alps (northern Italy)

In late winter 2024 (February–March), a fatal case of heterospecific amplexus was observed in a small artificial fountain (~6 m²) located at the Forum Franciscanum in Caslino d'Erba (northern Italy). Two adult females of Salamandra salamandra entered the water to deposit larvae and were repeatedly clasped dorsally by male Rana temporaria engaged in reproductive activity. Both salamanders subsequently died before releasing larvae. After hatching, anuran tadpoles consumed the carcasses. Although indiscriminate amplexus during breeding aggregations is well documented in anurans, fatal outcomes involving ovoviviparous urodeles are rarely reported. This observation suggests that in small, high-density breeding habitats, heterospecific amplexus may result in complete reproductive failure of syntopic species and indirect ecological consequences.