The circular tail-straddling walk of the clouded salamander, Aneides ferreus: a deviation from the highly conserved linear tail-straddling walk of the Plethodontidae

Abstract The family Plethodontidae is the most species-rich group of salamanders and although courtship observations are rather rare for some genera, behaviors are reported to be stereotyped across members of the whole family. In detail, courtship is characterized by a distinct behavior called linear tail-straddling walk, in which the female follows the male as he moves forward in a straight line. To better understand courtship behaviour in the Plethodontidae, we report here a description of the courtship behaviour of the clouded salamander (Aneides ferreus [Cope]), which deviates from the more common pattern. Our observations of over 20 complete courtships show that A. ferreus courtship is distinct from typical plethodontid patterns in three notable ways: (1) a novel, circular tail-straddling walk precedes the typical plethodontid linear tail-straddling walk, (2) the duration of courtship is much longer than in other plethodontids, and (3) females exhibit behaviours atypical of most plethodontid females. We discuss the possible evolutionary and ecological implications of these differences, some of which may have evolved in response to habitats where space for social interactions is limited.