Novel Courtship Behaviors in Three Small Eastern Plethodon Species

Abstract

Plethodontid salamanders provide an opportunity to investigate mating behaviors and pheromonal communication within the context of well-established phylogenetic relationships. Courtship in many members of the genus Plethodon has been well studied, but critical gaps exist in observations of pheromone delivery methods (vaccination or olfactory) in species phylogenetically intermediate between those having the two pheromone delivery methods. I observed courtship interactions in three small eastern plethodontids, Plethodon cinereus, Plethodon angusticlavius, and Plethodon richmondi. I documented several novel female behaviors, as well as interspecific variation in courtship patterns that otherwise have been highly conserved for over 70 million years. I confirmed that olfactory pheromone delivery occurs in P. angusticlavius, a species that is phylogenetically in the transition from vaccination to olfactory pheromone delivery within the genus Plethodon. The deviation from typical courtship patterns observed for the three study species revealed that females play a more active role in courtship than has previously been documented for Plethodon species.