Out of North Africa: Evolution and biogeography of Afro-Arabian dwarf tarantulas (Theraphosidae, Ischnocolinae)
Molecular Phylogenetics and Evolution 218: 108559.
Abstract
Large-scale vicariant events are expected to create congruent phylogeographic patterns among unrelated taxa. A continental-wide disjunction displayed by unrelated plant taxa across Afro-Arabia (the RAND flora pattern) has been traditionally explained as a consequence of late Miocene aridification of the region and the formation of the Sahara Desert. We implement genomic data (UCE), divergence time estimation and biogeographic analyses to uncover the origins of RAND pattern distribution in dwarf tarantula genus Ischnocolus Ausserer, 1871. The results suggest that the disjunct distribution of Ischnocolus resulted from ecological vicariance driven by the Middle Miocene climate cooling, predating the timing of the aridification of the region. Additionally, we delimit the boundaries of the genus Ischnocolus and assess its position within the tarantula phylogeny. As a consequence, we revalidate the genus Luphocemus Denis, 1960, which is endemic to North Africa.