Phylogenetic relationships of Mesobuthus eupeus (C.L. Koch, 1839) inferred from COI sequences (Scorpiones: Buthidae)

In this study, the first molecular phylogenetic analysis of Mesobuthus eupeus in Iran is presented based on sequence data of a ～ 700-base-pair fragment of cytochrome C oxidase, subunit I. Phylogenetic relationships were inferred using parsimony, maximum likelihood and Bayesian inference. The results support monophyly of M. eupeus, but there is a clear divergence between northern and southern clades. The northern clade includes four subspecies – M. e. eupeus, M. e. philippovitschi, M. e. afghanus and M. e. thersites; whereas the southern clade is comprised of two others – M. e. phillipsi and M. e. kirmanensis. Accordingly, possible scenarios for the evolution and phylogeographic structure of M. eupeus based on the geological history of the Iranian Plateau were proposed. The observation of two distinct lineages supports the proposal that M. eupeus might be a species complex composed of species with highly similar morphological features.     

Water exchange between mother and larvae in scorpions

Summary Scorpion larvae spend their first larval stage settled on their mother's back. Isolated larvae can also survive, but their survival probability is lower than it is if they remain on the back of the mother. Experiments with tritiated water suggest that a water exchange must take place between mother and larvae.