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Creators/Authors contains: "BAUER, AARON M"

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  1. The Nucras of the eastern Zambezi River basin region, comprising Zambia, Malawi and central Mozambique have been poorly studied. We re-evaluated the type specimens of Lacerta cameranoi Bedriaga, 1886 and L. tessellata pseudotessellata Bedriaga, 1886, both collected at Tete, Mozambique by Wilhelm Peters in the 1840s. Both are assignable to N. ornata, the most widespread Nucras in the region. However, an additional specimen collected from Tete is referrable to N. holubi, filling a collecting gap for this species between central Zimbabwe and southern Malawi. Nucras records from northeastern Zambia include several N. boulengeri, two photo-vouchered records, one unidentifiable and the other an enigmatic form not consistent with any known species, and a new species from Senga Hill, Northern Province. The new species, Nucras margaritae sp. nov., is known only from its holotype. It is morphologically similar to N. ornata, from which it is separated by 620 airline km, but is deeply genetically divergent from all congeners and is sister to the clade comprising N. holubi, N. ornata, N. damarana and N. intertexta. At least five species of Nucras, four currently named, inhabit the greater eastern Zambezi River basin.   
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    Free, publicly-accessible full text available May 8, 2026
  2. Abstract Among squamates, hemipenes are known to evolve rapidly and exhibit diverse shapes, sizes, and ornamentation. Croaking geckos (Aristelliger) are unique among geckos in exhibiting mineralized structures (hemibacula) in their hemipenes. We here describe the gross morphology of the hemibacula of each currently recognized species ofAristelliger, document hemibacular histology, and report on hemibaculum development. We confirm the presence of hemibacula in all currently recognized species and demonstrate that three distinct morphologies correspond to three putative clades in the genus. Histology revealed that hemibacula are superficially similar to chondroid bone and composed of mineralized dense connective tissue covered in a thin layer of epidermis with alcian‐positive cells embedded within a mineralized matrix. Additionally, we demonstrate that hemibacula do not develop until past the onset of sexual maturity and that hemibaculum length scales isometrically with body size. We hypothesize that hemibacula ofAristelligerdevelop via peramorphosis, a phenomenon also expressed in the cranial morphology of this genus. Additionally, we speculate on the functional significance of these enigmatic structures. 
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    Free, publicly-accessible full text available June 16, 2026
  3. The genus Rhoptropus comprises nine recognized species of diurnal geckos endemic to the arid regions of Angola and Namibia. Seven species occur in Angola, including the widespread R. boultoni and the poorly known Angolan endemics R. benguellensis and R. montanus, formerly recognized as subspecies of R. boultoni. While R. benguellensis is relatively widespread in the Angolan Escarpment highlands, R. montanus is geographically restricted to the Huíla Plateau. Recent fieldwork on the Serra da Neve inselberg, a herpetological diversity hotspot in southwestern Angola, revealed the presence of an undescribed species of Rhoptropus at an elevation of approximately 1600 m. An integrative taxonomic approach combining coloration, morphological and molecular data supports the recognition of this population as a distinct taxonomic unit with affinities to R. montanus, which we describe herein as Rhoptropus nivimontanus sp. nov. The discovery of a new species of Rhoptropus endemic to Serra da Neve is discussed in the biogeographic context of the region.  
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    Free, publicly-accessible full text available January 15, 2026
  4. Four species of the genusPanaspis–P. cabindae,P. wahlbergi,P. maculicollisandP. mocamedensis– are currently known from Angola. The analysis of recently collected specimens from Serra da Neve Inselberg, an isolated mountain located in northern Namibe Province, revealed unexpected taxonomic diversity in the group. Using an integrative taxonomy approach based on morphological and DNA sequence data, with both mitochondrial (16S) and nuclear (RAG-1) genes, we were able to distinguish two distinct populations, described here as two new species,Panaspis ericaesp. nov.andP. mundavambosp. nov.Both species are assumed to be endemic to the inselberg. This reinforces our notion of southwestern Angola as a hotspot of skink diversity, and highlights the urgent need for the conservation of Serra da Neve. 
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  5. The Serra da Neve inselberg in Namibe Province, southwestern Angola is the second highest peak of Angola with an elevation of 2489 m. It remains one of the least explored regions in the country, despite several endemic species having been recently described from this inselberg. Here we provide an inventory of the amphibian and reptile species ocurring in Serra da Neve and compare its fauna with that of the surrounding habitats at lower elevations. We also examine the phylogenetic affinities of the inselberg taxa. A total of 59 herpetological taxa were recorded for the Serra da Neve inselberg and its immediate surroundings. These include 11 species of amphibians, belonging to nine genera and seven different families, and 48 species of reptiles, belonging to 32 genera and 12 families. Of these, one amphibian and seven reptiles from seven different genera are strictly endemic, making the inselberg the richest region in southwestern Africa with respect to strict endemics, with one endemic reptile taxa per 127 km2. Not surprisingly, most of the recorded taxa belong to clades that are endemic, or at least strongly associated, with southern Africa, but two are representatives of central African clades, and another two are more closely related to eastern African highland taxa. We also provide comments on the threats to the conservation of this endemic-rich inselberg. 
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  6. During a recent survey of the Serra da Neve inselberg in southwestern Angola, a population of lance-skinks of the genus Acontias was found. Only three species of this genus have been recorded for the country so far — A. occidentalis, A. kgalagadi and A. jappi. Using an integrative approach and combining molecular and morphological data we found that the Serra da Neve population represents a new species, closely related to rupicolous species such as A. percivali and members of the A. occidentalis species complex. In this paper we describe this population as a new species, Acontias mukwando sp. nov. and provide brief comments on its conservation and biogeography. 
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  7. Abstract Lygodactylus is the most speciose gekkonid group in Africa, with several additional, candidate species already identified from previous studies. However, in mainland Africa, several groups remain only partially resolved, and there are several taxonomic inconsistencies. Lygodactylus gutturalis was described from Guinea-Bissau in the 1870s and since then, the species has been recorded from West to East Africa, and it is widely distributed through different biomes and ecoregions. However, this taxon has never been studied in detail. In this work, we use an integrative approach, including molecular phylogenetic analysis, morphometrics, skull osteology, and biogeography to provide the first systematic revision of the L. gutturalis species complex. The L. gutturalis complex is a subgroup within the L. picturatus group and includes nine well-differentiated species. We elevate Lygodactylus gutturalis dysmicus to full species status, recognize Lygodactylus depressus as the sister species to L. gutturalis, describe five new species (Lygodactylus kibera sp. nov., Lygodactylus karamoja sp. nov., Lygodactylus mirabundus sp. nov., Lygodactylus leopardinus sp. nov., and Lygodactylus gamblei sp. nov.), and propose an additional candidate species that requires further research. Also, in order to shed light on some taxonomic inconsistencies between the L. gutturalis and Lygodactylus angularis groups, we revisit the L. angularis group, within which we elevate Lygodactylus angularis heeneni and Lygodactylus angularis paurospilus to full species status. The L. gutturalis subgroup diversified during the Late Miocene (between 5–15 Mya), probably as a consequence of multiple vicariant events driven by the expansion of the African savannahs and the establishment of climatic refugia. 
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