Abstract:
The Ecuadorian horned anole (Anolis proboscis) is a slow-moving cryptic species endemic to the northwestern slopes of the Andes in Ecuador. Males of this species bear a rostral appendage that has been interpreted as an exaggerated trait resulting from sexual selection. Here, we describe thoroughly possible uses of the rostral appendage of A. proboscis in social interactions by filming and analyzing 11 matings and three male-male trials. We describe four types of displays by males, as well as male-female courtship behavior and male-male agonistic interactions. We found that the rostral appendage is used in social displays but not as a weapon in combat. Unlike other lizards with a rostral appendage, males of A. proboscis are born with this structure.