Meeting Abstract

P3.9  Wednesday, Jan. 6  Sexual Dimorphism in the Sensory Structures of the Northern Scorpion, Paruroctonus boreus MILLER, A L; FERNANDES, J *; University of Tampa; St. Petersburg College Fernandes.Jennifer@spcollege.edu

We investigated the sexual dimorphism and geographical variation in sensory structures used to locate mates in the northern scorpion Paruroctonus boreus. Males respond to the presence of conspecific pheromones from the same population but not to conspecific pheromones from allopatric populations. Mature males actively search for females during the mating season and therefore, thought to have greater selection pressure on the pectines, which contain the sensory receptors. We investigated sexual dimorphism of the pectines within and among populations using scanning electron microscopy. Four measurements were used to assess these differences. All measured variables were significantly larger in males than females, but only one variable significantly varied among populations. Our results suggest that P. boreus males have developed larger sensory structures to facilitate mate localization and the pressures driving the increase in size is not population specific.