Variation of reproductive effort between parthenogenetic and sexual populations of the scorpion Tityus columbianus

Abstract

Abstract. Geographic differences in reproductive effort were examined between sexual and parthenogenetic populations of the Colombian scorpion Tityus columbianus, from Iza (sexual) and from Mosquera (unisexual). The sexual females from Iza were significantly larger and had significantly greater relative litter mass (RLM) than the parthenogenetic ones from Mosquera. In both populations litter size increased significantly with female body size.Litter size and RLM in the sexuals averaged 12.7 and 0.49 respectively, and in the unisexuals 8 and 0.36. We suggest that the higher values are related to greater primary productivity at the Iza site.