Defensive behaviors of Tropidurus catalanensis Gudynas & Skuk, 1983 (Squamata, Tropiduridae)

Abstract

Tropidurus catalanensis Gudynas & Skuk, 1983 (Squamata, Tropiduridae) is a lizard species found in Argentina, Paraguay, Uruguay, and Brazil. Here, we present defensive behaviors performed by T. catalanensis, adding information about how these lizards avoid predation. Our observations were in an introduced urban population in the State of São Paulo, Brazil, where individuals performed immobility, locomotor escape by running and climbing, squirreling, tail waving, tail lifting, mouth opening, forced escape, and cloacal discharge. When approached by the potential predator, T. catalanensis tended to stay immobile, but always ran off with further approximation. After locomotor escape, some individuals displayed squirreling - i.e., flight from a side of tree or rock towards the opposite side of it - in order to conceal their presence and difficult visual detection. After flight, a T. catalanensis performed squirreling in a tree and climbed it along the trunk and a limb reaching a height of almost 6 m from the ground, which might difficult or impede capture by predators coming from below. Other individuals of T. catalanensis also did squirreling climbing up to lower heights on lower trees. When manipulated, a T. catalanensis undulated its tail trying to distract the potential predator in order to escape. Another T. catalanensis lifted its tail, which might also serve as a distraction to predators besides deceiving them by making a lizard look longer and/or bigger. While handled, some T. catalanensis opened their mouths in a threatening display and forced freeing. After capture, T. catalanensis discharged intestinal contents out of their cloaca. Discharges had solid and liquid fractions and repulsive taste and smell. The defensive behaviors reported here are likely advantageous for escaping and increasing chances of survival of lizards.