Pub Date : 2019-08-08DOI: 10.1080/21564574.2019.1645745
G. Coombs
ABSTRACT Predation risk may be high in small snakes and most small snakes are thought to avoid certain behaviours, such as basking in open areas to reduce predation risk. The extent to which this concealment limits predation during basking is not known, but available data suggests that such concealment may significantly reduce predation attempts. Using model snakes placed in the field, predation rates on small model snakes were tested, specifically whether attack rates differ between partially concealed model snakes and model snakes placed in open unconcealed positions. Results from the current study support previous studies that predation pressure was high (average = 22.15%), but was not significantly reduced by semi-sheltered basking. An important new finding of this study was the high number of model snakes that experience trampling by wild ungulates (average = 12.72%.) This suggests that snakes basking in open and sheltered areas are also at risk of being killed or injured through trampling by larger animals. This study makes an important contribution to understanding predation pressure in African snakes and highlights other threats that snakes are exposed to during basking and thermoregulation.
{"title":"Does partial concealment influence predation attempts on small model snakes in South Africa?","authors":"G. Coombs","doi":"10.1080/21564574.2019.1645745","DOIUrl":"https://doi.org/10.1080/21564574.2019.1645745","url":null,"abstract":"ABSTRACT Predation risk may be high in small snakes and most small snakes are thought to avoid certain behaviours, such as basking in open areas to reduce predation risk. The extent to which this concealment limits predation during basking is not known, but available data suggests that such concealment may significantly reduce predation attempts. Using model snakes placed in the field, predation rates on small model snakes were tested, specifically whether attack rates differ between partially concealed model snakes and model snakes placed in open unconcealed positions. Results from the current study support previous studies that predation pressure was high (average = 22.15%), but was not significantly reduced by semi-sheltered basking. An important new finding of this study was the high number of model snakes that experience trampling by wild ungulates (average = 12.72%.) This suggests that snakes basking in open and sheltered areas are also at risk of being killed or injured through trampling by larger animals. This study makes an important contribution to understanding predation pressure in African snakes and highlights other threats that snakes are exposed to during basking and thermoregulation.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2019-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2019.1645745","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49090450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-08-05DOI: 10.1080/21564574.2019.1646324
K. Tolley, K. Hopkins, J. D. da Silva
ABSTRACT There are notable examples of repeated evolution of ecomorphs within groups of closely related species, these are typically viewed as remarkable cases of natural selection. In most cases, directional selection for certain phenotypic traits under specific (and differing) environmental conditions is implicated. Differing ecomorphological forms for closely related species (or for populations within a species) have been documented for several lineages of South African dwarf chameleons (Bradypodion), although this pattern is not ubiquitous across the genus. Within one species, Bradypodion pumilum, two ecomorphs have been observed, these differ in terms of morphology, performance, ecology and habitat, yet genetic differences (mtDNA) were not apparent, with shared haplotypes across the ecomorphs. We investigated whether more sensitive genetic markers (eight microsatellite loci) would show population level structure between ecomorphs, which could indicate lack of gene flow across the ecological (habitat) boundary. Our results suggest that the two ecomorphs are distinct at a population level, implying that gene flow is absent or reduced and that the two ecomorphs are on separate evolutionary trajectories. Given that mtDNA could not detect population structure, we infer that the ecological boundary between ecomorphs is relatively recent in evolutionary history. The two ecomorphs are distinctive in terms of their morphology, ecology, habitat and functional traits, these differences are likely driven and maintained by reproductive isolation across the habitat boundary.
{"title":"Genetic structure associated with habitat diversification supports the independent evolution of ecomorphs in Bradypodion pumilum","authors":"K. Tolley, K. Hopkins, J. D. da Silva","doi":"10.1080/21564574.2019.1646324","DOIUrl":"https://doi.org/10.1080/21564574.2019.1646324","url":null,"abstract":"ABSTRACT There are notable examples of repeated evolution of ecomorphs within groups of closely related species, these are typically viewed as remarkable cases of natural selection. In most cases, directional selection for certain phenotypic traits under specific (and differing) environmental conditions is implicated. Differing ecomorphological forms for closely related species (or for populations within a species) have been documented for several lineages of South African dwarf chameleons (Bradypodion), although this pattern is not ubiquitous across the genus. Within one species, Bradypodion pumilum, two ecomorphs have been observed, these differ in terms of morphology, performance, ecology and habitat, yet genetic differences (mtDNA) were not apparent, with shared haplotypes across the ecomorphs. We investigated whether more sensitive genetic markers (eight microsatellite loci) would show population level structure between ecomorphs, which could indicate lack of gene flow across the ecological (habitat) boundary. Our results suggest that the two ecomorphs are distinct at a population level, implying that gene flow is absent or reduced and that the two ecomorphs are on separate evolutionary trajectories. Given that mtDNA could not detect population structure, we infer that the ecological boundary between ecomorphs is relatively recent in evolutionary history. The two ecomorphs are distinctive in terms of their morphology, ecology, habitat and functional traits, these differences are likely driven and maintained by reproductive isolation across the habitat boundary.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2019.1646324","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42976626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-03DOI: 10.1080/21564574.2018.1509138
Rabah Mamou, F. Marniche, Mansour Amroun, J. Exbrayat, A. Herrel
ABSTRACT We studied the composition and seasonal changes in diet and prey selection in the wall lizard Podarcis vaucheri of the Djurdjura Mountains throughout its activity period, from April to October 2014. The analysis of 238 faecal pellets revealed 1 206 prey items distributed in 19 prey categories. The most important prey categories were: Formicidae, Coleoptera, Aranea, Homoptera, and Orthoptera. Significant seasonal variation in the taxonomic composition of the diet and prey availability was found. A significant difference in diet composition was observed between males and females in spring. This lizard species displayed a more diverse dietary spectrum during this period, followed by a slight decrease in summer. However, a severe decrease in the food niche breadth was observed in autumn, resulting in a high consumption of ants. A comparison of diet composition and prey availability showed that lizards exhibited a clear selection of certain prey types, in contrast to what is often suggested for lacertid lizards.
{"title":"Seasonal variation in diet and prey availability in the wall lizard Podarcis vaucheri (Boulenger, 1905) from the Djurdjura Mountains, northern Algeria","authors":"Rabah Mamou, F. Marniche, Mansour Amroun, J. Exbrayat, A. Herrel","doi":"10.1080/21564574.2018.1509138","DOIUrl":"https://doi.org/10.1080/21564574.2018.1509138","url":null,"abstract":"ABSTRACT We studied the composition and seasonal changes in diet and prey selection in the wall lizard Podarcis vaucheri of the Djurdjura Mountains throughout its activity period, from April to October 2014. The analysis of 238 faecal pellets revealed 1 206 prey items distributed in 19 prey categories. The most important prey categories were: Formicidae, Coleoptera, Aranea, Homoptera, and Orthoptera. Significant seasonal variation in the taxonomic composition of the diet and prey availability was found. A significant difference in diet composition was observed between males and females in spring. This lizard species displayed a more diverse dietary spectrum during this period, followed by a slight decrease in summer. However, a severe decrease in the food niche breadth was observed in autumn, resulting in a high consumption of ants. A comparison of diet composition and prey availability showed that lizards exhibited a clear selection of certain prey types, in contrast to what is often suggested for lacertid lizards.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2018.1509138","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48163191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-08DOI: 10.1080/21564574.2018.1462064
A. Kotzé, Taryn M. C. Ralph, Lisa N. Barrow, Jeanne Tarrant, L. Preez, L. Preez, M. T. Madisha, D. Dalton
ABSTRACT The Endangered Pickersgill’s Reed Frog (Hyperolius pickersgilli) is endemic to South Africa and restricted to the KwaZulu-Natal (KZN) coast. The natural habitat of H. pickersgilli is limited to fragmented patches of coastal reed-bed wetland, the majority of which continues to undergo transformation and degradation caused by urbanisation, agriculture, mining and forestry. These changes have resulted in the steady reduction of suitable, quality habitat and severe fragmentation. In the current study we employed mitochondrial DNA and species-specific microsatellites markers (developed in the current study) to investigate the genetic structure and diversity of H. pickersgilli. Genetic markers revealed moderate to high levels of genetic diversity throughout the remnant groups and absence of specific phylogeographic structure among individuals sampled across twelve localities throughout the range of the species. Results from the current study indicate that gene flow between H. pickersgilli individuals is not restricted, whereby neighbouring groups may interact with each other through continued migration, thereby facilitating possible range expansion should habitat be available. However, the need for continued conservation of the H. pickersgilli population through the protection and management of its natural habitats should remain a top priority in order to conserve representative levels of genetic diversity.
{"title":"Lack of phylogeographic structure in the endangered Pickersgill’s Reed Frog; Hyperolius pickersgilli (Raw, 1982)","authors":"A. Kotzé, Taryn M. C. Ralph, Lisa N. Barrow, Jeanne Tarrant, L. Preez, L. Preez, M. T. Madisha, D. Dalton","doi":"10.1080/21564574.2018.1462064","DOIUrl":"https://doi.org/10.1080/21564574.2018.1462064","url":null,"abstract":"ABSTRACT The Endangered Pickersgill’s Reed Frog (Hyperolius pickersgilli) is endemic to South Africa and restricted to the KwaZulu-Natal (KZN) coast. The natural habitat of H. pickersgilli is limited to fragmented patches of coastal reed-bed wetland, the majority of which continues to undergo transformation and degradation caused by urbanisation, agriculture, mining and forestry. These changes have resulted in the steady reduction of suitable, quality habitat and severe fragmentation. In the current study we employed mitochondrial DNA and species-specific microsatellites markers (developed in the current study) to investigate the genetic structure and diversity of H. pickersgilli. Genetic markers revealed moderate to high levels of genetic diversity throughout the remnant groups and absence of specific phylogeographic structure among individuals sampled across twelve localities throughout the range of the species. Results from the current study indicate that gene flow between H. pickersgilli individuals is not restricted, whereby neighbouring groups may interact with each other through continued migration, thereby facilitating possible range expansion should habitat be available. However, the need for continued conservation of the H. pickersgilli population through the protection and management of its natural habitats should remain a top priority in order to conserve representative levels of genetic diversity.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2019-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2018.1462064","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44054670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-07DOI: 10.1080/21564574.2018.1509139
S. Krishnan, Caleb OFORI-BOATENG, M. Fujita, A. Leaché
ABSTRACT West Africa is a region characterised by high species diversity and endemism, making it an ideal region to study the evolution of genetic and phenotypic differentiation. Species in this region often vary in morphology and genetics; however, the specific drivers of these differences have not been clearly identified. Focusing on populations in Ghana, we tested for correlations between geography, genetic diversity, morphology and ecology in the West African rainbow lizard (Agama picticauda). Genetic data were collected from 102 specimens using double-digest restriction site-associated DNA sequencing (ddRADseq) and the final data matrix included 5 976 loci and 20 624 single nucleotide polymorphisms (SNPs). Morphological data were collected from 42 specimens and included 6 meristic and 4 mensural characters. Ecological data were obtained from the WorldClim database to a resolution of 30 arcseconds. Population structure analyses supported up to five distinct populations of A. picticauda in Ghana. Discriminant function analyses were used to classify samples using the morphological data and ecological data. Ecology showed the strongest correlation with population genetic structure, whereas morphological data were only able to weakly differentiate three populations. We discuss the factors that might be responsible for correlations between phenotypes and genotypes in the context of A. picticauda natural history.
{"title":"Geographic variation in West African Agama picticauda: insights from genetics, morphology and ecology","authors":"S. Krishnan, Caleb OFORI-BOATENG, M. Fujita, A. Leaché","doi":"10.1080/21564574.2018.1509139","DOIUrl":"https://doi.org/10.1080/21564574.2018.1509139","url":null,"abstract":"ABSTRACT West Africa is a region characterised by high species diversity and endemism, making it an ideal region to study the evolution of genetic and phenotypic differentiation. Species in this region often vary in morphology and genetics; however, the specific drivers of these differences have not been clearly identified. Focusing on populations in Ghana, we tested for correlations between geography, genetic diversity, morphology and ecology in the West African rainbow lizard (Agama picticauda). Genetic data were collected from 102 specimens using double-digest restriction site-associated DNA sequencing (ddRADseq) and the final data matrix included 5 976 loci and 20 624 single nucleotide polymorphisms (SNPs). Morphological data were collected from 42 specimens and included 6 meristic and 4 mensural characters. Ecological data were obtained from the WorldClim database to a resolution of 30 arcseconds. Population structure analyses supported up to five distinct populations of A. picticauda in Ghana. Discriminant function analyses were used to classify samples using the morphological data and ecological data. Ecology showed the strongest correlation with population genetic structure, whereas morphological data were only able to weakly differentiate three populations. We discuss the factors that might be responsible for correlations between phenotypes and genotypes in the context of A. picticauda natural history.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2018.1509139","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44755213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-11DOI: 10.1080/21564574.2017.1422153
Mirjam Dubke, C. Hipsley, Johannes Müller
ABSTRACT The anatomy of African lacertid lizards (Lacertidae: Eremiadini) is poorly known, which has hindered a better understanding of their evolutionary relationships. This applies especially to the East African clade, which includes the genera Nucras, Latastia, Philochortus, Pseuderemias and Heliobolus. We present a detailed description of the skull osteology of the genus Heliobolus using X-ray microcomputed tomography and compare its morphology to the above lacertid taxa. Because the genus Heliobolus includes species of doubtful validity and affinities (Heliobolus neumanni and Heliobolus nitidus), we also present a detailed intrageneric comparison and construct a morphological character matrix that we analyse against a phylogenetic backbone derived from previous molecular studies. Heliobolus lugubris and Heliobolus spekii can be well characterised as a monophyletic group on the basis of a short postorbital and a continuously broad posterior margin of the parietal, differing from H. nitidus and other members of the East African clade in an overall low degree of ossification and reduced ventral extension of the frontal bone. Our preliminary phylogenetic analysis suggests that the genus Heliobolus is currently polyphyletic. We propose that the name H. neumanni be officially retracted, because specimens assigned to this species show very different morphologies relative to each other and are placed in different parts of the tree in our analysis. Also, the type specimen is lost and no specimens were collected from the type locality. H. nitidus shows a signal towards the genus Latastia. A definitive, new generic assignment of H. nitidus must await further investigations based on molecular data.
{"title":"Comparative skull osteology and preliminary systematic revision of the African lizard genus Heliobolus (Squamata: Lacertidae)","authors":"Mirjam Dubke, C. Hipsley, Johannes Müller","doi":"10.1080/21564574.2017.1422153","DOIUrl":"https://doi.org/10.1080/21564574.2017.1422153","url":null,"abstract":"ABSTRACT The anatomy of African lacertid lizards (Lacertidae: Eremiadini) is poorly known, which has hindered a better understanding of their evolutionary relationships. This applies especially to the East African clade, which includes the genera Nucras, Latastia, Philochortus, Pseuderemias and Heliobolus. We present a detailed description of the skull osteology of the genus Heliobolus using X-ray microcomputed tomography and compare its morphology to the above lacertid taxa. Because the genus Heliobolus includes species of doubtful validity and affinities (Heliobolus neumanni and Heliobolus nitidus), we also present a detailed intrageneric comparison and construct a morphological character matrix that we analyse against a phylogenetic backbone derived from previous molecular studies. Heliobolus lugubris and Heliobolus spekii can be well characterised as a monophyletic group on the basis of a short postorbital and a continuously broad posterior margin of the parietal, differing from H. nitidus and other members of the East African clade in an overall low degree of ossification and reduced ventral extension of the frontal bone. Our preliminary phylogenetic analysis suggests that the genus Heliobolus is currently polyphyletic. We propose that the name H. neumanni be officially retracted, because specimens assigned to this species show very different morphologies relative to each other and are placed in different parts of the tree in our analysis. Also, the type specimen is lost and no specimens were collected from the type locality. H. nitidus shows a signal towards the genus Latastia. A definitive, new generic assignment of H. nitidus must await further investigations based on molecular data.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2018-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2017.1422153","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49547383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-02DOI: 10.1080/21564574.2017.1413015
Leonor B. Soares, L. Ceríaco, M. P. Marques, C. Bastos-Silveira, Lauren Scheinberg, D. James Harris, A. Brehm, J. Jesus
ABSTRACT Leaf-litter skinks of the genus Panaspis are currently represented in the oceanic islands of the Gulf of Guinea by two species, Panaspis africana and P. annobonensis. Here we describe a third species, Panaspis thomensis sp. nov., endemic to São Tomé Island. Data from previous studies and a new phylogenetic analysis using the mitochondrial 16S gene shows that the new species is genetically divergent and reciprocally monophyletic with respect to P. africana. Morphological data (scalation and morphometry) identify consistent, yet subtle, phenotypic differences between the two island populations. We also confirm that P. annobonensis represents a valid species, sister to the species pair P. africana + P. thomensis sp. nov., based on both molecular and morphological evidence. This description raises the number of known Panaspis species in the Gulf of Guinea oceanic islands to three, with consequences for the interpretation of local endemicity. ZooBank—Panaspis thomensis: lsid: zoobank.org:act:A1E69D28-CF4C-4070-BBCC-91E39C21DBA6
{"title":"Review of the leaf-litter skinks (Scincidae: Panaspis) from the Gulf of Guinea Oceanic Islands, with the description of a new species","authors":"Leonor B. Soares, L. Ceríaco, M. P. Marques, C. Bastos-Silveira, Lauren Scheinberg, D. James Harris, A. Brehm, J. Jesus","doi":"10.1080/21564574.2017.1413015","DOIUrl":"https://doi.org/10.1080/21564574.2017.1413015","url":null,"abstract":"ABSTRACT Leaf-litter skinks of the genus Panaspis are currently represented in the oceanic islands of the Gulf of Guinea by two species, Panaspis africana and P. annobonensis. Here we describe a third species, Panaspis thomensis sp. nov., endemic to São Tomé Island. Data from previous studies and a new phylogenetic analysis using the mitochondrial 16S gene shows that the new species is genetically divergent and reciprocally monophyletic with respect to P. africana. Morphological data (scalation and morphometry) identify consistent, yet subtle, phenotypic differences between the two island populations. We also confirm that P. annobonensis represents a valid species, sister to the species pair P. africana + P. thomensis sp. nov., based on both molecular and morphological evidence. This description raises the number of known Panaspis species in the Gulf of Guinea oceanic islands to three, with consequences for the interpretation of local endemicity. ZooBank—Panaspis thomensis: lsid: zoobank.org:act:A1E69D28-CF4C-4070-BBCC-91E39C21DBA6","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2018-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2017.1413015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46858548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-02-27DOI: 10.1080/21564574.2017.1398186
J. Šmíd, H. Engelbrecht, J. Taft, N. Telford, Buyisile G. Makhubo, A. Bauer, K. Tolley
ABSTRACT Pachydactylus is the most species-rich reptile genus in southern Africa. Most species are habitat specialists adapted to hyper-arid conditions of the Namibian and north-western South African xeric regions. Although a fair number of phylogenetic studies and taxonomic revisions have been published, some species still remain rather enigmatic. In the ten years since the taxonomic revision of the weberi group, some of the species have not been recorded and our knowledge on their distribution, phylogenetic affinities, or intraspecific variability is limited or non-existent. Pachydactylus goodi is one such species. In this study, we report a newly discovered population of P. goodi in the Richtersveld National Park, South Africa, which considerably extends the known range of the species. In addition, the results of our phylogenetic analyses indicate that P. goodi is paraphyletic with respect to P. atorquatus. Although there is a striking colour polymorphism observed between these two species, the level of genetic differentiation within the goodi-atorquatus clade is comparable with intraspecific variability observed in other Pachydactylus species. As a result of these findings, which are further supported by morphological similarity of the two species, we conclude that they represent a single species and synonymise P. goodi with P. atorquatus.
{"title":"A contribution to the phylogeny and taxonomy of the Pachydactylus weberi group (Squamata: Gekkonidae): a case of intraspecific colour polymorphism confounding taxonomy","authors":"J. Šmíd, H. Engelbrecht, J. Taft, N. Telford, Buyisile G. Makhubo, A. Bauer, K. Tolley","doi":"10.1080/21564574.2017.1398186","DOIUrl":"https://doi.org/10.1080/21564574.2017.1398186","url":null,"abstract":"ABSTRACT Pachydactylus is the most species-rich reptile genus in southern Africa. Most species are habitat specialists adapted to hyper-arid conditions of the Namibian and north-western South African xeric regions. Although a fair number of phylogenetic studies and taxonomic revisions have been published, some species still remain rather enigmatic. In the ten years since the taxonomic revision of the weberi group, some of the species have not been recorded and our knowledge on their distribution, phylogenetic affinities, or intraspecific variability is limited or non-existent. Pachydactylus goodi is one such species. In this study, we report a newly discovered population of P. goodi in the Richtersveld National Park, South Africa, which considerably extends the known range of the species. In addition, the results of our phylogenetic analyses indicate that P. goodi is paraphyletic with respect to P. atorquatus. Although there is a striking colour polymorphism observed between these two species, the level of genetic differentiation within the goodi-atorquatus clade is comparable with intraspecific variability observed in other Pachydactylus species. As a result of these findings, which are further supported by morphological similarity of the two species, we conclude that they represent a single species and synonymise P. goodi with P. atorquatus.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2018-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2017.1398186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43829507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-02-26DOI: 10.1080/21564574.2017.1398187
M. Hofmeyr, W. Branch
ABSTRACT Since 1957, all padlopers were considered Homopus, which was an anomaly, because only two species have four claws on the front and hind limbs. The revival of the genus Chersobius for the five-toed species (signatus, boulengeri and solus) now limits Homopus to the four-toed species (areolatus and femoralis). Molecular data indicate that Homopus is paraphyletic with two well-supported clades: the four-toed Homopus in one clade and the five-toed Chersobius together with Chersina angulata in a second clade. There are numerous distinct morphological and ecological differences between the genera. All Chersobius species have a single, large inguinal scute, whereas the number is variable in Homopus. The midline pectoral scute of Chersobius is consistently longer, and the nuchal scute shorter, than in Homopus. The fourth to fifth vertebral suture is narrow in Homopus and broad in Chersobius. Forelimb scales also differ with 3–4 large rows and 5–6 smaller rows, respectively, in Homopus and Chersobius. Chersobius males have a plastral concavity and Homopus males not. Two Chersobius species (C. signatus and C. boulengeri) are distinguishable from Homopus by having 12 or more marginal scutes, whereas Homopus species have 11 or fewer. The glans penes are respectively V-shaped and heart-shaped in Homopus and Chersobius. Ecological differences include that Chersobius species are rupicolous and inhabit arid regions, whereas Homopus species inhabit more mesic habitats. Homopus females produce multi-egg clutches and tend to be bigger compared to single-egg clutching Chersobius females. Females of all species are larger than conspecific males, and all males have larger shell openings than females have. ZooBank—urn:lsid:zoobank.org:pub: 18229454-6662-46F3-8B15-836BF2AC38EB
{"title":"The padloper’s tortuous path (Chelonia: Testudinidae): Two genera, not one","authors":"M. Hofmeyr, W. Branch","doi":"10.1080/21564574.2017.1398187","DOIUrl":"https://doi.org/10.1080/21564574.2017.1398187","url":null,"abstract":"ABSTRACT Since 1957, all padlopers were considered Homopus, which was an anomaly, because only two species have four claws on the front and hind limbs. The revival of the genus Chersobius for the five-toed species (signatus, boulengeri and solus) now limits Homopus to the four-toed species (areolatus and femoralis). Molecular data indicate that Homopus is paraphyletic with two well-supported clades: the four-toed Homopus in one clade and the five-toed Chersobius together with Chersina angulata in a second clade. There are numerous distinct morphological and ecological differences between the genera. All Chersobius species have a single, large inguinal scute, whereas the number is variable in Homopus. The midline pectoral scute of Chersobius is consistently longer, and the nuchal scute shorter, than in Homopus. The fourth to fifth vertebral suture is narrow in Homopus and broad in Chersobius. Forelimb scales also differ with 3–4 large rows and 5–6 smaller rows, respectively, in Homopus and Chersobius. Chersobius males have a plastral concavity and Homopus males not. Two Chersobius species (C. signatus and C. boulengeri) are distinguishable from Homopus by having 12 or more marginal scutes, whereas Homopus species have 11 or fewer. The glans penes are respectively V-shaped and heart-shaped in Homopus and Chersobius. Ecological differences include that Chersobius species are rupicolous and inhabit arid regions, whereas Homopus species inhabit more mesic habitats. Homopus females produce multi-egg clutches and tend to be bigger compared to single-egg clutching Chersobius females. Females of all species are larger than conspecific males, and all males have larger shell openings than females have. ZooBank—urn:lsid:zoobank.org:pub: 18229454-6662-46F3-8B15-836BF2AC38EB","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2018-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2017.1398187","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42327945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-02-20DOI: 10.1080/21564574.2017.1402094
L. Rudie, Patrick J. Lewis
ABSTRACT Wormian bones are accessory bones found between cranial elements. These rare bones vary greatly in size, shape and placement. Wormian bones are well-known in mammals, notably in humans and chimpanzees, but not in lizards. Here we examine the genus Zygaspis, a southern African amphisbaenian with complex cranial sutures, for the presence of Wormian bones. Skulls from seven of the eight species of Zygaspis were examined for the presence of Wormian bones. Because of their small size, complex sutures and delicate nature, high-resolution X-ray computed tomography was used to produce 3D models of the skulls. We discovered three Wormian bones in the interdigitated frontoparietal suture of Z. kafuensis. This discovery is the first known record of Wormian bones in a lizard and it is one of the few reports of them in the Squamata. The presence of Wormian bones in a head-first, burrowing squamate allows for a possible functional role to be hypothesised. Additional studies on a variety of squamate taxa are now needed, particularly in burrowing groups with interdigitated sutures, to improve our understanding of these rare cranial elements.
{"title":"The first record of Wormian bones in lizards","authors":"L. Rudie, Patrick J. Lewis","doi":"10.1080/21564574.2017.1402094","DOIUrl":"https://doi.org/10.1080/21564574.2017.1402094","url":null,"abstract":"ABSTRACT Wormian bones are accessory bones found between cranial elements. These rare bones vary greatly in size, shape and placement. Wormian bones are well-known in mammals, notably in humans and chimpanzees, but not in lizards. Here we examine the genus Zygaspis, a southern African amphisbaenian with complex cranial sutures, for the presence of Wormian bones. Skulls from seven of the eight species of Zygaspis were examined for the presence of Wormian bones. Because of their small size, complex sutures and delicate nature, high-resolution X-ray computed tomography was used to produce 3D models of the skulls. We discovered three Wormian bones in the interdigitated frontoparietal suture of Z. kafuensis. This discovery is the first known record of Wormian bones in a lizard and it is one of the few reports of them in the Squamata. The presence of Wormian bones in a head-first, burrowing squamate allows for a possible functional role to be hypothesised. Additional studies on a variety of squamate taxa are now needed, particularly in burrowing groups with interdigitated sutures, to improve our understanding of these rare cranial elements.","PeriodicalId":49247,"journal":{"name":"African Journal of Herpetology","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2018-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21564574.2017.1402094","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46305888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：