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The rcptiles and amphibians oFtheKarnanjab area and adjacent Darnaraland, Namibia, are discussed, based on a series of nearly 500 specimens collected during recent field work in the region and information derived from more than 900 museum records and a survey of the literature. A total of 14 amphibian and 88 reptile species are h o w to inhabit the region. Representatives of psammophine snakes and the lizard genera Pachydactylus and Mabuya constitute an especially significant proponion of the local fauna. The fauna is transitional between southern arid and tropical and is similar to that of southwestern Angola. The well-defined edge of the Great Escarpment. emphasized in the region by the Gmotberg, divides the study area into discrete eastern (mcsic. high elevation) and western (xcric. low elevation) portions, characterized by the presence of some closely related species pairs.

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The lacertid genus Pedioplanis is a moderately speciose group of small-bodied, cryptically-colored lizards found in arid habitats throughout southern Africa. Previous phylogenetic work on Pedioplanis has determined its placement within the broader context of the Lacertidae, but interspecific relations within the genus remain unsettled, particularly within the P. undata species complex, a group largely endemic to Namibia. We greatly expanded taxon sampling for members of the P. undata complex and other Pedioplanis, and generated molecular sequence data from 1,937 bp of mtDNA (ND2 and cyt b) and 2,015 bp of nDNA (KIF24, PRLR, RAG-1) which were combined with sequences from GenBank resulting in a final dataset of 455 individuals. Both maximum likelihood and Bayesian analyses recover similar phylogenetic results and reveal the polyphyly of P. undata and P. inornata as presently construed. We con- firm that P. husabensis is sister to the group comprising the P. undata complex plus the Angolan sister species P. huntleyi + P. haackei and demonstrate that P. benguelensis lies outside of this clade in its entirety. The complex itself comprises six species including P. undata, P. inornata, P. rubens, P. gaerdesi and two previously undescribed entities. Based on divergence date estimates, the P. undata species complex began diversifying in the late Miocene (5.3 ± 1.6 MYA) with the most recent cladogenetic events dating to the Plio- cene (2.6 ± 1.0 MYA), making this assemblage relatively young compared to the genus Pedioplanis as a whole, the origin of which dates back to the mid-Miocene (13.5 ± 1.8 MYA). Using an integrative approach, we here describe Pedioplanis branchi sp. nov. and Pedioplanis mayeri sp. nov. representing northern populations previously assigned to P. inornata and P. undata, respectively. These entities were first flagged as possible new species by Berger-Dell’mour and Mayer over thirty years ago but were never formally described. The new species are supported chiefly by differences in coloration and by unique amino acid substitutions. We provide comprehensive maps depicting historical records based on museum specimens plus new records from this study for all members of the P. undata complex and P. husabensis. We suggest that climatic oscillations of the Upper Miocene and Pliocene-Pleistocene era in concert with the formation of biogeographic barriers have led to population isolation, gene flow restrictions and ultimately cladogenesis in the P. undata complex.

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Although reptile diversity in Africa is high, it is poorly represented in Angola, with just 257 species known. Despite its greater surface area and habitat diversity Angola has significantly lower lacertid lizard diversity than adjacent Namibia. This is particularly notable in African sand lizards (Pedioplanis), where 10 species (two endemic) are known from Namibia but only two are recorded from adjacent Angola. Pedioplanis benguelensis was described from Angola, but its taxonomic status is problematic and it was previously synonymised with P. namaquensis. All other Angolan Pedioplanis were referred to Namibian P. undata, although this taxon is now known to comprise a complex of at least five different species and the relationship of Angolan material to this complex has not been assessed. In this study, we investigated the phylogenetic placement of Angolan Pedioplanis using two mitochondrial (ND2 and 16S) and one nuclear (RAG-1) markers. A Bayesian analysis was conducted on 21 samples from Angola, combined with existing data for 45 individuals from GenBank and three additional samples from central Namibia. The phylogeny demonstrates that P. benguelensis is a valid species and that it is not the sister taxon to P. namaquensis with which it has been morphologically confused. In addition, Angolan lacertids previously referred to P. undata are not conspecific with any of the Namibian or South African species in that complex. Rather, there is strong support for the presence in Angola of additional species of Pedioplanis, which form a wellsupported sister clade to the P. undata complex (sensu stricto) of Namibia and two ofwhich are described herein. These discoveries highlight the need for further biodiversity surveys in Angola, as similar increases in species diversity in other Angolan taxa might be found given sufficient investment in biodiversity surveys.