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1.
Sci Data ; 11(1): 191, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346970

RESUMO

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Mamíferos , Vertebrados , Plantas , África
2.
PeerJ ; 8: e8526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32257631

RESUMO

A recent multilocus molecular phylogeny of the large dragon lizards of the genus Smaug Stanley et al. (2011) recovered a south-eastern clade of two relatively lightly-armoured, geographically-proximate species (Smaug warreni (Boulenger, 1908) and S. barbertonensis (Van Dam, 1921)). Unexpectedly, S. barbertonensis was found to be paraphyletic, with individuals sampled from northern Eswatini (formerly Swaziland) being more closely related to S. warreni than to S. barbertonensis from the type locality of Barberton in Mpumalanga Province, South Africa. Examination of voucher specimens used for the molecular analysis, as well as most other available museum material of the three lineages, indicated that the 'Eswatini' lineage-including populations in a small area on the northern Eswatini-Mpumalanga border, and northern KwaZulu-Natal Province in South Africa-was readily distinguishable from S. barbertonensis sensu stricto (and S. warreni) by its unique dorsal, lateral and ventral colour patterns. In order to further assess the taxonomic status of the three populations, a detailed morphological analysis was conducted. Multivariate analyses of scale counts and body dimensions indicated that the 'Eswatini' lineage and S. warreni were most similar. In particular, S. barbertonensis differed from the other two lineages by its generally lower numbers of transverse rows of dorsal scales, and a relatively wider head. High resolution Computed Tomography also revealed differences in cranial osteology between specimens from the three lineages. The 'Eswatini' lineage is described here as a new species, Smaug swazicus sp. nov., representing the ninth known species of dragon lizard. The new species appears to be near-endemic to Eswatini, with about 90% of its range located there. Our study indicates that S. barbertonensis sensu stricto is therefore a South African endemic restricted to an altitudinal band of about 300 m in the Barberton-Nelspruit-Khandizwe area of eastern Mpumalanga Province, while S. warreni is endemic to the narrow Lebombo Mountain range of South Africa, Eswatini and Mozambique. We present a detailed distribution map for the three species, and a revised diagnostic key to the genus Smaug.

3.
Zootaxa ; 4061(3): 201-26, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-27395495

RESUMO

The girdled lizard genus Cordylus is represented in Angola by two species, Cordylus angolensis and C. machadoi, separated from their nearest congeners by over 700 km. Here we describe a new species, Cordylus namakuiyus sp. nov., endemic to the arid lowlands west of the southern Angolan escarpment. Phylogenetic analysis using three mitochondrial and eight nuclear genes shows that the low-elevation forms and the proximate, high-elevation species C. machadoi are genetically divergent and reciprocally monophyletic, and together form the earliest diverging lineage of the northern Cordylus clade. Morphological data, collected using computed tomography and traditional techniques (scalation and morphology), identify consistent phenotypic differences between these high- and low-elevation species and allows for a detailed description of the osteology and osteodermal arrangements of the new species. A series of 50 specimens, collected during the 1925 Vernay expedition to southwestern Angola and housed at the American Museum of Natural History, are assigned to the new species, although the identity of Cordylus from northern Namibia remains ambiguous and requires further investigation.


Assuntos
Lagartos/classificação , Angola , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Clima Desértico , Ecossistema , Feminino , Lagartos/anatomia & histologia , Lagartos/crescimento & desenvolvimento , Masculino , Namíbia , Tamanho do Órgão
4.
Mol Phylogenet Evol ; 82 Pt A: 31-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25307118

RESUMO

The Afroedura nivaria species complex (A. nivaria, A. karroica, A. amatolica, A. tembulica and A. halli) is a morphologically conservative group of medium-sized flat geckos endemic to South Africa and Lesotho. Species are allopatric, as are some populations within species that are separated by large expanses of unsuitable habitat. Because of this isolation of populations we hypothesised that several cryptic species may be present. To investigate this hypothesis we constructed a molecular phylogeny using multiple markers, and included representatives of other Afroedura species. Bayesian inference and maximum likelihood analyses (439bp 16S, 593bp ND4, 948bp RAG1) strongly supported the genetic distinctiveness of the five described species. However, the A. nivaria species complex as currently described is not monophyletic, as A. karroica was positioned outside a clade containing all other Afroedura species, and A. pondolia (which was presumed to belong to a different species complex) was recovered within the A. nivaria complex. Several distinct clades within A. halli and A. nivaria were also recovered, and the narrowly-distributed A. amatolica consisted of two highly divergent clades. We also conducted a multivariate analysis using 19 morphological characters to investigate whether the clades recovered by the phylogeny were distinct in terms of head, body and limb shape. The analysis showed some variation between clades in terms of locomotor apparatus (forelimbs and feet), head and body dimensions, but overall the morphological differences were minor. This morphological conservatism in the A. nivaria complex may be a result of adaptation to similar microhabitats. Exclusive of A. karroica, the results suggest that there are at least nine species in this complex, of which four are cryptic and undescribed.


Assuntos
Especiação Genética , Lagartos/classificação , Filogenia , Animais , Teorema de Bayes , Funções Verossimilhança , Lagartos/anatomia & histologia , Lagartos/genética , Modelos Genéticos , Análise de Sequência de DNA , África do Sul
5.
Zootaxa ; 3750: 465-93, 2013 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25113712

RESUMO

We constructed a molecular phylogeny of the African plated lizard family Gerrhosauridae using two mitochondrial markers (ND2, 732 bp; 16S, 576 bp) and one nuclear marker (PRLR, 538 bp). This analysis showed that the subfamily Gerrhosaurinae consists of five major clades which we interpret as representing five genera. The genera Tetradactylus and Cordylosaurus were each recovered as monophyletic, but Gerrhosaurus as currently conceived is paraphyletic, consisting of three distinct genus-level assemblages. The two clades consisting of Gerrhosaurus major Duméril, 1851 and Gerrhosaurus validus Smith, 1849 are both described here as new genera, namely Broadleysaurus Bates & Tolley gen. nov. and Matobosaurus Bates & Tolley gen. nov., respectively. Two subspecies of 'Gerrhosaurus major' that were historically separated on the basis of differences in colour pattern are not reciprocally monophyletic, so Gerrhosaurus bottegoi Del Prato, 1895 is relegated to the synonomy of Broadleysaurus major (Duméril, 1851) comb. nov., which is rendered monotypic. Gerrhosaurus validus maltzahni De Grys, 1938 is genetically and morphologically well differentiated from G. v. validus and the two taxa also occur in allopatry. We therefore re-instate the former as Matobosaurus maltzahni (De Grys, 1938) comb. nov., rendering Matobosaurus validus (Smith, 1849) comb. nov. a monotypic species. Our analysis also showed that Gerrhosaurus sensu stricto comprises two major subclades, one consisting of Gerrhosaurus typicus (Smith, 1837) + Gerrhosaurus skoogi Andersson, 1916, and the other containing the remaining species. In this latter subclade we show that west-Central African Gerrhosaurus nigrolineatus Hallowell, 1857 is most closely related to Gerrhosaurus auritus Boettger, 1887 rather than to G. nigrolineatus from East and Southern Africa. The west-Central African clade of G. nigrolineatus differs from the East and Southern African clade by a p-distance of 13.0% (ND2) and 6.9% (16S), and can be differentiated morphologically. We accordingly apply the name Gerrhosaurus intermedius Lönnberg, 1907 comb. nov. to populations from Kenya, Uganda, Rwanda, Tanzania, Malawi, Mozambique, Zimbabwe and South Africa previously identified under the name G. nigrolineatus. Our analysis also confirms that Gerrhosaurus bulsi Laurent, 1954 is a distinct species and sister taxon to a clade containing G. nigrolineatus, G. auritus and G. intermedius. The latter four taxa form a closely-related 'G. nigrolineatus species complex' with a widespread distribution in Africa. Most closely related to this complex of species is Gerrhosaurus flavigularis Wiegmann, 1828 which has an extensive range in East and Southern Africa, and displays genetic substructure which requires further investigation. The status of Gerrhosaurus multilineatus Bocage, 1866, and Angolan populations referred to G. nigrolineatus, remains problematic.


Assuntos
Lagartos/classificação , África , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Ecossistema , Feminino , Lagartos/anatomia & histologia , Lagartos/genética , Masculino , Dados de Sequência Molecular , Filogenia
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