Systematic Revision of the Genus <i>Charmus</i> Karsch, 1879 (Scorpiones: Buthidae), and Assessment of Its Phylogenetic Position Within Buthidae C. L. Koch, 1837 Using Ultraconserved Elements

Abstract

India and Sri Lanka are known to exhibit high levels of biological diversity with many endemic taxa, such as the enigmatic scorpion genus Charmus Karsch, 1879. Members of this genus are rarely encountered in the field and are also known to be morphologically very similar, which impedes their systematic assessment. Our dedicated efforts towards sampling the members of the genus resulted in the collection of important material, which allowed us to carry out a thorough systematic revision of the genus using an integrated taxonomic approach. We propose several taxonomic changes based on the results of a detailed morphological study supported by molecular data. Charmus indicus Hirst, 1915 is synonymized with Charmus laneus Karsch, 1879, owing to the lack of morphological differences and low genetic divergence between the two taxa. We designate a neotype for Charmus sinhagadensis Tikader and Bastawade, 1983, and describe a new species from Sirumalai (Tamil Nadu, India). Moreover, we provide the first molecular phylogeny of Charmus based on Cytochrome c Oxidase subunit I (COI), 16S rRNA (16S) and 28S rRNA (28S) genes. The phylogenetic position of the genus within the family Buthidae C. L. Koch, 1837 is also tested using an independent genome-wide dataset (Ultraconserved Elements). Topological congruence and discrepancies between the phylogenies generated with Sanger sequences and the Ultraconserved Elements are commented on, and the reliability of these datasets when evaluating phylogenetic relationships at different hierarchical levels is further discussed.

Keywords

• Indian sub-continent
• endemism
• biodiversity
• new species
• multi-locus phylogeny
• genomics