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Zhao Z, Conradie W, Pietersen DW, Jordaan A, Nicolau G, Edwards S, Riekert S, Heideman N. Diversification of the African legless skinks in the subfamily Acontinae (Family Scincidae). Mol Phylogenet Evol 2023; 182:107747. [PMID: 36849095 DOI: 10.1016/j.ympev.2023.107747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 02/15/2023] [Accepted: 02/22/2023] [Indexed: 02/27/2023]
Abstract
Cladogenic diversification is often explained by referring to climatic oscillations and geomorphic shifts that cause allopatric speciation. In this regard, southern Africa retains a high level of landscape heterogeneity in vegetation, geology, and rainfall patterns. The legless skink subfamily Acontinae occurs broadly across the southern African subcontinent and therefore provides an ideal model group for investigating biogeographic patterns associated with the region. A robust phylogenetic study of the Acontinae with comprehensive coverage and adequate sampling of each taxon has been lacking up until now, resulting in unresolved questions regarding the subfamily's biogeography and evolution. In this study, we used multi-locus genetic markers (three mitochondrial and two nuclear) with comprehensive taxon coverage (all currently recognized Acontinae species) and adequate sampling (multiple specimens for most taxa) of each taxon to infer a phylogeny for the subfamily. The phylogeny retrieved four well-supported clades in Acontias and supported the monophyly of Typhlosaurus. Following the General Lineage Concept (GLC), many long-standing phylogenetic enigmas within Acontias occidentalis and the A. kgalagadi, A. lineatus and A. meleagris species complexes, and within Typhlosaurus were resolved. Our species delimitation analyses suggest the existence of hidden taxa in the A. occidentalis, A. cregoi and A. meleagris species groups, but also suggest that some currently recognized species in the A. lineatus and A. meleagris species groups, and within Typhlosaurus, should be synonymised. We also possibly encountered "ghost introgression" in A. occidentalis. Our inferred species tree revealed a signal of gene flow, which implies possible cross-over in some groups. Fossil evidence calibration dating results showed that the divergence between Typhlosaurus and Acontias was likely influenced by cooling and increasing aridity along the southwest coast in the mid-Oligocene caused by the opening of the Drake Passage. Further cladogenesis observed in Typhlosaurus and Acontias was likely influenced by Miocene cooling, expansion of open habitat, uplifting of the eastern Great Escarpment (GE), and variation in rainfall patterns, together with the effect of the warm Agulhas Current since the early Miocene, the development of the cold Benguela Current since the late Miocene, and their co-effects. The biogeographic pattern of the Acontinae bears close resemblance to that of other herpetofauna (e.g., rain frogs and African vipers) in southern Africa.
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Affiliation(s)
- Zhongning Zhao
- Department of Zoology and Entomology, University of the Free State, Bloemfontein, South Africa; Department of Genetics, University of the Free State, Bloemfontein, South Africa.
| | - Werner Conradie
- Port Elizabeth Museum (Bayworld), P.O. Box 13147, Humewood, Port Elizabeth 6013, South Africa; Department of Nature Conservation Management, Natural Resource Science and Management Cluster, Faculty of Science, George Campus, Nelson Mandela University, George, South Africa
| | - Darren W Pietersen
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Adriaan Jordaan
- Department of Zoology and Entomology, University of the Free State, Bloemfontein, South Africa
| | - Gary Nicolau
- Zoology & Entomology Molecular Lab, Department of Zoology and Entomology, Rhodes University, Makhanda, South Africa
| | - Shelley Edwards
- Zoology & Entomology Molecular Lab, Department of Zoology and Entomology, Rhodes University, Makhanda, South Africa
| | - Stephanus Riekert
- Department of Information and Communication Technology Services, University of the Free State, Bloemfontein, South Africa
| | - Neil Heideman
- Department of Zoology and Entomology, University of the Free State, Bloemfontein, South Africa
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Glynne E, Daza JD, Bauer AM. Surface sculpturing in the skull of gecko lizards (Squamata: Gekkota). Biol J Linn Soc Lond 2020. [DOI: 10.1093/biolinnean/blaa144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Abstract
It has previously been stated that geckos are characterized by smooth cranial bones bearing no sculpturing; however, there are many exceptions. Here we systematically characterize variation in sculpturing in cranial bones across all seven gekkotan families and examine patterns of evolutionary transitions in these traits on a multigene molecular gekkotan phylogeny to elucidate trends in phenotypic diversification in bone sculpturing. Over 195 species were reviewed using specimens where smooth, grooved, pitted and rugose sculpturing patterns were found. Of the 26 cranial bones, only seven (premaxilla, maxilla, nasal, prefrontal, frontal, parietal and postorbitofrontal) were found to bear sculpturing across more than three species. Sculpturing was found to extend beyond these seven bones onto either the dentary, surangular and/or quadrate within five species. Phylogenetic analysis showed that sculpturing evolved recently and repeatedly in several distinct lineages. The remaining 19 skull bones were smooth, except in the five species above, supporting the suggestion that smooth skull bones were ancestral in gekkotans. There is no apparent relationship between body size and the presence of bone sculpturing. The functional significance, if any, of sculpturing requires further investigation.
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Affiliation(s)
- Elizabeth Glynne
- Department of Biological Sciences, Sam Houston State University, Huntsville, TX, USA
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Juan D Daza
- Department of Biological Sciences, Sam Houston State University, Huntsville, TX, USA
| | - Aaron M Bauer
- Department of Biology and Center for Biodiversity and Ecosystem Stewardship, Villanova University, Villanova, PA, USA
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Busschau T, Conradie W, Daniels SR. One species hides many: Molecular and morphological evidence for cryptic speciation in a thread snake (Leptotyphlopidae:
Leptotyphlops sylvicolus
Broadley & Wallach, 1997). J ZOOL SYST EVOL RES 2020. [DOI: 10.1111/jzs.12401] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Theo Busschau
- Department of Botany & Zoology University of Stellenbosch Matieland South Africa
| | - Werner Conradie
- Port Elizabeth Museum Humewood South Africa
- School of Natural Resource Management, George Campus Nelson Mandela University George South Africa
| | - Savel R. Daniels
- Department of Botany & Zoology University of Stellenbosch Matieland South Africa
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Bates MF, Stanley EL. A taxonomic revision of the south-eastern dragon lizards of the Smaug warreni (Boulenger) species complex in southern Africa, with the description of a new species (Squamata: Cordylidae). PeerJ 2020; 8:e8526. [PMID: 32257631 PMCID: PMC7102504 DOI: 10.7717/peerj.8526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 01/07/2020] [Indexed: 11/20/2022] Open
Abstract
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.
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Affiliation(s)
- Michael F Bates
- Department of Herpetology, National Museum, Bloemfontein, South Africa.,Department of Zoology and Entomology, University of the Free State, Bloemfontein, South Africa
| | - Edward L Stanley
- Department of Herpetology, Florida Museum of Natural History, Gainesville, FL, USA
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Evidence for cryptic diversification in a rupicolous forest-dwelling gecko (Gekkonidae: Afroedura pondolia) from a biodiversity hotspot. Mol Phylogenet Evol 2019; 139:106549. [DOI: 10.1016/j.ympev.2019.106549] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 11/22/2022]
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Integrative taxonomy of Afrotropical Ornithodoros (Ornithodoros) (Acari: Ixodida: Argasidae). Ticks Tick Borne Dis 2018; 9:1006-1037. [DOI: 10.1016/j.ttbdis.2018.03.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 03/21/2018] [Accepted: 03/22/2018] [Indexed: 01/26/2023]
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Mouton LF, Flemming A, Bates M, Broeckhoven C. The relationship between generation gland morphology and armour in Dragon Lizards (Smaug): a reassessment of ancestral states for the Cordylidae. AMPHIBIA-REPTILIA 2018. [DOI: 10.1163/15685381-20181032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
To substantiate the claim of a relationship between generation gland morphology and degree of body armour in cordylid lizards, we studied the nine species in the genus Smaug. We predicted that well armoured species in this clade will have multi-layer generation glands, and lightly armoured species two-layer glands. Gland type was determined using standard histological techniques after sectioning a glandular patch of one adult male per species. A total of 133 specimens were examined for data on tail and occipital spine lengths (which were used as indicators of armour). We found that species with multi-layer generation glands (S. giganteus, S. breyeri, and S. vandami) have relatively long tail and occipital spines, while species with two-layer glands (S. mossambicus, S. regius, S. barbertonensis, S. warreni, and an undescribed species) have relatively short spines. Smaug depressus possesses both multi-layer and two-layer glands, and this variation was linked to regional variation in spine length. An ancestral state reconstruction for the Cordylidae showed that the two-layer state always results from the reduction of layers from a multi-layer precursor, and that reduction always culminates in two-layer glands and not in one-layer glands. This finding suggests that the one-layer state in the Ninurta-Chamaesaura-Pseudocordylus clade is most probably plesiomorphic, and therefore the ancestral state at the Cordylidae and Cordylinae nodes. Given the observed relationship between type of generation gland and body armour, this finding would suggest that the most recent common ancestor of the Cordylidae was lightly armoured.
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Affiliation(s)
- le Fras Mouton
- 1Department of Botany & Zoology, Stellenbosch University, Private bag X1, Matieland 7602, South Africa
| | - Alexander Flemming
- 1Department of Botany & Zoology, Stellenbosch University, Private bag X1, Matieland 7602, South Africa
| | - Michael Bates
- 2Department of Herpetology, National Museum, P.O. Box 266, Bloemfontein 9300, South Africa
| | - Chris Broeckhoven
- 1Department of Botany & Zoology, Stellenbosch University, Private bag X1, Matieland 7602, South Africa
- 3Theoretical Ecology Group, Department of Mathematical Sciences, Stellenbosch University, Private bag X1, Matieland 7602, South Africa
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