Cryptic diversity and dynamic chromosome evolution in Alpine scorpions (Euscorpiidae: Euscorpius)
Petr Nguyen and his colleagues focused on cytogenetic and molecular phylogenetic analyzes to determine the variability and population structure of today's scorpion populations, both chromosomal and genetic.
Figure: Phylogenetic analysis of three species of scorpions of the genus Euscorpius. Credit: Štundlová et al. 2019.
In the present study, the authors examined three scorpion species of the subgenus Euscorpius (Alpiscorpius) from the European Alps using cytogenetic and molecular phylogenetic approaches to determine the variation and population structure of extant lineages at both chromosome and genetic level, and to provide an insight into the species diversification histories. We detected considerable intraspecific variability in chromosome complements and localization of the 18S rDNA loci in all studied species. Such chromosome differences were noticeable as the existence of three [in E. (A.) alpha and E. (A.) germanus] or four [in E. (A.) gamma] range-restricted karyotypic races. These races differed from one another either by 2n [in E. (A.) alpha 2n = 54, 60, 90; in E. (A.) gamma 2n = 58, 60, 88, 86–92], or by the karyotypic formula [in E. (A.) germanus 2n = 34m + 12sm; 36m + 10sm; 42m + 4sm]. Using mitochondrial (16S rRNA, COI) and nuclear (28S rDNA) genetic markers, we examined genetic variation and reconstructed phylogenetic relationships among the karyotypic races. Both approaches provided evidence for the existence of ten deeply divergent lineages exhibiting the features of local endemics and indicating the presence of cryptic species. Molecular dating analyses suggest that these lineages diversified during the Plio-Pleistocene and this process was presumably accompanied by dynamic structural changes in the genome organization. (source: https://www.sciencedirect.com/science/article/pii/S1055790318303282?via%3Dihub)
Štundlová, J., Šmíd, J., Nguyen, P., Šťáhlavský, F. 2019. Cryptic diversity and dynamic chromosome evolution in Alpine scorpions (Euscorpiidae: Euscorpius). Molecular Phylogenetics and Evolution 134: 152–163.
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