Meeting Abstract

84.5  Thursday, Jan. 7  A comparative look at the defensive complex of scorpions. VAN DER MEIJDEN, A.*; SOUSA, P.; HARRIS, D.J.; CIBIO, University of Porto; CIBIO, University of Porto; CIBIO, University of Porto frog@arievandermeijden.nl

The two key features of the time-tested body plan of scorpions are the pinchers (chelae), and the stinger (telson). Scorpion chelae and telson functionally overlap in defense and subjugation of prey, and therefore provide an excellent but mostly unexplored system for the study of functional trade-offs. We present an exploratory analysis of the variation in the morphology and performance of these two systems. The chelae are multifunctional structures serving in prey capture, defense, courtship and mating, burrowing, climbing and serve as a platform for many sensory organs. In a broad sampling over several families, pinch force is highly correlated with chela height, similar to findings in crabs, whereas the aspect ratio of chela height to length even better explains the observed differences in pinch force. The shape of chelae across the scorpionidae is further explored in this light. The metasoma (“tail”, actually a continuation of the body) carries the telson. High variability in metasoma shape and size is well known within the scorpionidae, in some cases related to specialized aspects of their behavior and biology. We provide the first data on the performance of the metasoma in defensive venom delivery.