First record of facultative paedomorphism in the Kosswig’s newt Lissotriton (vulgaris) kosswigi (Freytag, 1955) (Urodela; Salamandridae), endemic to northwestern Turkey

Abstract

Facultative paedomorphism is regularly observed in salamanders, including newts of the Lissotriton vulgaris group. We document the first record of paedomorphism in L. (v.) kosswigi from a locality near Karasu, in the vicinity of Sakarya, Turkey. We compare measurements of 5 paedomorphic individuals with those of 10 metamorphic individuals from the same population and with measurements taken from the literature. Paedomorphs are on average bigger than metamorphs; intriguingly, the opposite pattern has been observed in the Turkish L. (v.) schmidtlerorum.