Kolotl, n. gen. (Scorpiones: Diplocentridae), a New Scorpion Genus from Mexico

Phylogeographic Patterns in a Semi-Lithophilous Burrowing Scorpion, Opistophthalmus pallipes, from South Africa

Southern Africa has a diverse endemic scorpion fauna, but a paucity of information currently confounds conservation of the group. Phylogeographic approaches represent a useful tool to identify the patterns and processes which underpin scorpion diversity, but these studies are lacking for southern African species. Among southern African scorpions, the semi-lithophilous Opistophthalmus pallipes has strict habitat requirements, and a distribution historically subjected to profound environmental turnover. As such, the species offers a model system to investigate the interplay between intrinsic and extrinsic factors as drivers of diversity and endemism. To investigate spatial genetic patterns within O. pallipes and the possible drivers thereof, the current study combines mitochondrial DNA and ecological information under a phylogeographic approach. The species is characterized by several genetically discrete and divergent populations. The factors which shape these genetic patterns appear to be both intrinsically (ecological specificity) and extrinsically (landscape structure and ecogeographic conditions) influenced, with major divergences corresponding to periods of profound environmental changes. Taken together, the findings of this study provide evidence of spatial genetic isolation and genetic diversity within a stenotopic southern African scorpion species. These findings partly explain the staggering diversity and endemism in southern African scorpions, but further phylogeographic studies are necessary to propose conservation scenarios for this group.

eadem figura manet: Measuring morphological convergence in diplocentrid scorpions (Arachnida : Scorpiones : Diplocentridae) under a multilocus phylogenetic framework

Morphology still plays a key role in the systematics and phylogenetics of most of the scorpion families and genera, including the Diplocentridae Karsch, 1880. The monophyly of this family, and the monophyly of its two subfamilies is supported by morphological characters; however, neither hypothesis has been tested using molecular data. The lack of a molecular phylogeny has prevented the study of the evolution of morphology within the family. Here, we examine the morphological evolution of several key character systems in diplocentrid systematics. We tested the monophyly of the Diplocentridae, and subsequently the validity of its two subfamilies using a five-locus phylogeny. We examined the variation and evolution of the shape of the carapace, the external surface of the pedipalp patella and the retrolateral surface of the pedipalp chelae of males and females. We also examined the phylogenetic signal of discrete and continuous characters previously reported. We show that Diplocentridae is monophyletic, but Nebinae is nested within Diplocentrinae. Therefore, Nebinae is synonymised with Diplocentrinae (new synonymy). Finally, we show that a new character system proposed here, tarsal spiniform and macrosetal counts, retains high phylogenetic signal and circumscribes independently evolving substructures within this character system.

Scorpions from Mexico: From Species Diversity to Venom Complexity

Scorpions are among the oldest terrestrial arthropods, which are distributed worldwide, except for Antarctica and some Pacific islands. Scorpion envenomation represents a public health problem in several parts of the world. Mexico harbors the highest diversity of scorpions in the world, including some of the world's medically important scorpion species. The systematics and diversity of Mexican scorpion fauna has not been revised in the past decade; and due to recent and exhaustive collection efforts as part of different ongoing major revisionary systematic projects, our understanding of this diversity has changed compared with previous assessments. Given the presence of several medically important scorpion species, the study of their venom in the country is also important. In the present contribution, the diversity of scorpion species in Mexico is revised and updated based on several new systematic contributions; 281 different species are recorded. Commentaries on recent venomic, ecological and behavioral studies of Mexican scorpions are also provided. A list containing the most important peptides identified from 16 different species is included. A graphical representation of the different types of components found in these venoms is also revised. A map with hotspots showing the current knowledge on scorpion distribution and areas explored in Mexico is also provided.