Abstract
The majority of species in Australia’s most diverse vertebrate genus Ctenotus Storr were diagnosed and described based on morphological data prior to the wide availability of molecular phylogenetic data to interpret taxonomic relationships and boundaries. The C. labillardieri (Duméril & Bibron) species group comprises seven taxa endemic to the biodiversity hotspot of southwestern Western Australia. A recent analysis provided a phylogeny for most species in this group and described a range-restricted species of immediate conservation concern. However, that study was unable to examine the molecular divergence of the species C. delli Storr due to a lack of tissue samples. Newly available samples allowed us to examine the taxonomic distinctiveness of this species and C. catenifer Storr which is very similar in morphology. Our combined molecular and morphological analyses show these two species to be conspecific. Therefore, we designate the name C. catenifer a junior synonym of C. delli and provide a redescription and revised diagnosis of a single morphologically variable species.
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