Abstract

A recent molecular phylogeny of the agamid genus Pseudotrapelus, distributed in the rocky areas of North Africa and the Arabian
Peninsula, revealed the presence of a genetically distinct lineage around the city of Riyadh in central Saudi Arabia. With the inclusion
of additional specimens, we were able to describe this lineage as a new species, P. tuwaiqensis sp. nov., confined to the Tuwaiq
Escarpment, thus endemic to central Saudi Arabia. Our results of morphological examinations and molecular analyses, using three
mitochondrial (COI, 16S, ND4-tRNAs) and two nuclear (c-mos, MC1R) gene fragments, show the new species is genetically differentiated
and phylogenetically close to P. sinaitus and P. chlodnickii.