Zoological Journal of the Linnean Society, Nov 25, 2011
Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Ca... more Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Caribbean. We estimated phylogenetic relationships among sphaerodactyl genera using both separate and combined analyses of seven nuclear genes. Relationships among genera were incongruent at different loci and phylogenies were characterized by short, in some cases zero-length, internal branches and poor phylogenetic support at most nodes. We recovered a polyphyletic Coleodactylus, with Coleodactylus amazonicus being deeply divergent from the remaining Coleodactylus species sampled. The C. amazonicus lineage possessed unique codon deletions in the genes PTPN12 and RBMX while the remaining Coleodactylus species had unique codon deletions in RAG1. Topology tests could not reject a monophyletic Coleodactylus, but we show that short internal branch lengths decreased the accuracy of topology tests because there were not enough data along these short branches to support one phylogenetic hypothesis over another. Morphological data corroborated results of the molecular phylogeny, with Coleodactylus exhibiting substantial morphological heterogeneity. We identified a suite of unique craniofacial features that differentiate C. amazonicus not only from other Coleodactylus species, but also from all other geckos. We describe this novel sphaerodactyl lineage as a new genus, Chatogekko gen. nov. We present a detailed osteology of Chatogekko, characterizing osteological correlates of miniaturization that provide a framework for future studies in sphaerodactyl systematics and biology.
The mourning gecko (Lepidodactylus lugubris) is a nocturnal, parthenogenetic species that has bee... more The mourning gecko (Lepidodactylus lugubris) is a nocturnal, parthenogenetic species that has been introduced in Colombia. Despite more than 70 years of collecting activity in the country, there has yet to be a thorough evaluation of its distribution in Colombia. Here we review all records from eight museum collections, along with literature reports, to generate a locality map documenting this gecko's distribution in space and time. Additionally, new sightings are reported and its range expansion in the Cauca rift valley is discussed.
Phylogenetic relationships among gekkotan lizards were estimated from five nuclear protein-coding... more Phylogenetic relationships among gekkotan lizards were estimated from five nuclear protein-coding genes in separate and combined analyses using maximum parsimony, maximum likelihood and Bayesian analyses. All analyses recovered a monophyletic transAtlantic gecko clade (Phyllodactylidae) consisting of the genera Asaccus, Haemodracon, Homonota, Phyllodactylus, Phyllopezus, Ptyodactylus, Tarentola and Thecadactylus. No other phylogenetic or taxonomic hypotheses have proposed linking these genera, which have been consistently grouped with other taxa outside of the clade. In this paper, we determine the relationships of this new clade to other major gekkotan groups, evaluate previous phylogenetic hypotheses regarding constituent members of this novel clade, and critically examine the use of historically important morphological characters in gekkotan systematics as they relate to this novel clade, specifically-phalangeal formulae, hyoid morphology and external structure of the toepads.
Recent molecular phylogenetic work has found that Breviceps Merrem, 1820 comprises two major clad... more Recent molecular phylogenetic work has found that Breviceps Merrem, 1820 comprises two major clades, one of which, the B. mossambicus group, is widely distributed across southern sub-Saharan Africa. This group is notable for harboring abundant cryptic diversity. Of the four most recently described Breviceps species, three are members of this group, and at least five additional lineages await formal description. Although Breviceps has long been known to occur in Angola, no contemporary material has been collected until recently. The three most widespread taxa, B. adspersus, B. mossambicus, and B. poweri, may all occur in Angola, but accurate species assignment remains challenging given the rampant morphological similarity between these taxa, and, until recently, the lack of genetic resources. Phylogenetic, morphological, and acoustic analyses of recently collected samples from disparate localities within Angola provide evidence for an undescribed species that is sister to B. poweri. The new species can be diagnosed from its sister taxon by lacking pale spots along the flanks, a pale patch above the vent, and a short, dark band below the nares (all present in B. poweri). Additionally, the male advertisement call differs from the three other Breviceps that might occur in Angola in having both a longer interval between consecutive calls and a higher average dominant frequency. We here describe this lineage as a distinct species, currently only known from Angola, and discuss the presence of other Breviceps taxa within Angola.
We use 3100 bp of mitochondrial (ND2, ND4) and nuclear (RAG1, phosducin) DNA sequence data to rec... more We use 3100 bp of mitochondrial (ND2, ND4) and nuclear (RAG1, phosducin) DNA sequence data to recover phylogenetic relationships among 14 of the 16 recognized taxa of the lizard genus Paroedura as well as two undescribed forms. These geckos are endemic to Madagascar and the Comores and are popularly kept and bred by herpetoculturalists. The closest relative of Paroedura is another Indian Ocean leaf-toed gecko, Ebenavia. Both Bayesian inference and maximum parsimony strongly support the monophyly of two major clades within Paroedura that conflict with existing species group assignments based on scale characteristics. Our well-resolved tree elucidates a biogeographic pattern in which eastern Paroedura are most basal and western and southwestern species form a monophyletic group. Our data demonstrate the phylogenetic utility of phosducin, a novel marker in squamate phylogenetics, at the intrageneric level.
Molecular Phylogenetics and Evolution, Sep 1, 2016
Despite an abundance of phylogenetic studies focused on intrageneric relationships of members of ... more Despite an abundance of phylogenetic studies focused on intrageneric relationships of members of the Mabuya group, the intergeneric relationships have remained difficult to resolve. The most-persistent unresolved regions of the phylogeny of the group include: (1) the placement of the Middle-Eastern Trachylepis with respect to the Afro-Malagasy Trachylepis and its taxonomic status; (2) the phylogenetic position of the Cape Verdean Chioninia within the larger Mabuya group; (3) support for the placement of Dasia with respect to the entire group; and (4) the phylogenetic placement of Eutropis novemcarinata with respect to other Eutropis and Dasia. In this study, we include representatives of all these taxa as well as African Eumecia and Neotropical Mabuya. We seek to address these phylogenetic and systematic issues by generating a well-resolved and supported phylogeny for the Mabuya group as a whole that can be used to develop a stable taxonomy and reconstruct the geographic patterns of diversification within the group. To meet these goals, we built a large multi-locus dataset of 11 markers (nine nuclear and two mitochondrial), and performed concatenated and species tree analyses to generate a well-supported phylogeny for the group. Statistical topology tests reject the monophyly of Middle-Eastern Trachylepis with Afro-Malagasy Trachylepis, and to reflect monophyly we place the Middle-Eastern species into a previously described genus, Heremites. Cape-Verdean Chioninia are resolved as the strongly supported sister-group to Afro-Malagasy Trachylepis. Monophyly of the Southeast-Asian genera, Eutropis and Dasia, is not supported, with a clade composed of Dasia+Eutropis novemcarinata more closely related to the rest of the Mabuya group than to the remaining Eutropis. The phylogenetic position of E. novemcarinata renders Eutropis polyphyletic, and we therefore describe and place E. novemcarinata into a new monotypic genus, Toenayar, to preserve monophyly among the genera. In light of these novel findings, we review and discuss the historical biogeography of the entire Mabuya group.
Introduction Geckos (infraorder Gekkota) are among the most prominent and species-rich herpetofau... more Introduction Geckos (infraorder Gekkota) are among the most prominent and species-rich herpetofaunal elements in most parts of the Old World tropics. While Africa, Madagascar, southern Asia and Australia each have endemic gecko radiations, few span multiple ...
This article may be used for research, teaching and private study purposes. Any substantial or sy... more This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan, sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
ABSTRACT In 1831 Sir Andrew Smith described a new genus and species of amphibian, Tremeropugus ty... more ABSTRACT In 1831 Sir Andrew Smith described a new genus and species of amphibian, Tremeropugus typicus, from South Africa. The description, which appeared in the obscure and short‐lived South African Quarterly Journal, has been overlooked for almost 175 years. Tremeropugus A. Smith, 1831 is a subjective junior synonym of Xenopus Wagler, 1827, whilst Tremeropugus typicus is almost certainly a subjective junior synonym of Bufo laevis Daudin, 1802.
We employed nuclear and mitochondrial DNA sequence data to investigate relationships within the g... more We employed nuclear and mitochondrial DNA sequence data to investigate relationships within the gekkonid genus Nactus and between Nactus and other gekkonid genera. Nuclear (RAG-1, PDC) and mitochondrial (ND2) data provide strong support for conflicting patterns of relationship among bisexual New Guinean species of Nactus and the unisexual oceanic form N. pelagicus. This may be explained by an ancient mitochondrial introgression event between N. sphaerodactylodes and N. vankampeni, a recent selective sweep of mitochondrial DNA throughout N. vankampeni, and gene conflict stemming from the hybrid event that gave rise to N. pelagicus. Strong support from all data partitions is obtained for the sister group relationship of Nactus to a clade consisting of the Australian Heteronotia and the Southeast Asian Dixonius. Putative synapomorphies of the Nactus/Heteronotia/Dixonius clade include the reduction of the second phalanx of digit IV of the manus and the presence of regular rows of keeled (sometimes multicarinate) dorsal tubercles on the dorsum. Nactus and Heteronotia both include parthenogenetic species formed via hybridogenesis. This is rare among geckos, and vertebrates in general, and at some level may also be synapomorphic. Dixonius is not known to have any all-female species, but "D. siamensis" consists of multiple chromosome "races" that mirror morphologically cryptic, but karyotypically distinct, species in the other two genera. The strong support for the Nactus/Heteronotia/Dixonius clade demonstrates that the leaf-toed digital morphology of Dixonius has evolved multiple times within the Gekkonidae and suggests that superficial digital morphology may be misleading with respect to gekkonid suprageneric relationships.
Journal of Zoological Systematics and Evolutionary Research, Sep 26, 2012
ABSTRACT The Miocene gecko in amber, Sphaerodactylus dommeli, is one of the best-preserved fossil... more ABSTRACT The Miocene gecko in amber, Sphaerodactylus dommeli, is one of the best-preserved fossil gekkotan species; nonetheless, its identity has been ques-tioned and it has been insinuated to be an iguanian referable to the mega-diverse genus Anolis. In this paper, we provide digital X‐rays and new osteo-logical evidence that include 11 characters that reaffirms its placement within the infraorder Gekkota and eight characters that specifically place this fossil within the species-rich genus Sphaerodactylus, in which it was originally described. This contribution seeks to eliminate remaining scepticism about the generic allocation of this species, and to provide a reliable calibration point for ongoing research in squamate phylogenetics, especially for biogeographical studies and molecular dating inference. This contribution also reviews many diagnostic characters for the two genera in question, which is critical for the correct identification of amber-embedded specimens representing the rich Hispaniolan lizard paleocommunity.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, Dec 27, 2017
Well-resolved phylogenetic hypotheses and ontogenetic data are often necessary for investigating ... more Well-resolved phylogenetic hypotheses and ontogenetic data are often necessary for investigating the evolution of structural novelty. The Sphaerodactylidae comprises 12 genera of predominantly miniaturized geckos. The genera Aristelliger and Teratoscincus are exceptions, with taxa reaching snout-to-vent lengths far exceeding those of other sphaerodactylids. These two genera possess enigmatic, supraorbital ossifications-parafrontal bones-which are encountered nowhere else among squamates. At the time of their discovery, these structures were believed to be the result of evolutionary convergence. Although relationships between other sphaerodactylids remain unresolved, recent molecular and morphological data have supported a close relationship between Aristelliger and Teratoscincus. We investigated the ontogeny of parafrontal bones to better understand relationships between sphaerodactylid body size and the presence of parafrontals, and to evaluate whether ontogenetic data support the homology of parafrontals between Aristelliger and Teratoscincus. We hypothesize that the parafrontals of Aristelliger and Teratoscincus are homologous and that there is a threshold body size in sphaerodactylids below which parafrontals do not develop, thus explaining their absence from the miniaturized taxa. The presence of parafrontals was investigated in all sphaerodactylid genera using cleared-andstained, radiographed, and skeletonized specimens. Total surface area of parafrontals was measured for seven species of Aristelliger and six species of Teratoscincus throughout their ontogeny. Histology was used to investigate the cellular composition of the parafrontals throughout their ontogeny. Our data suggest that parafrontals have evolved in parallel from a homologous, parafrontal precursor and that the onset of parafrontal development is not strictly dependent on a threshold body size.
... Gekkonidae) revisited: new insights from a molecular phylogeny ELI GREENBAUM, AARON M. BAUER ... more ... Gekkonidae) revisited: new insights from a molecular phylogeny ELI GREENBAUM, AARON M. BAUER AND TODD R. JACKMAN Department of Biology, Villanova University, 800 Lancaster Ave., Villanova, PA 19085, USA [email protected] ...
We published a phylogenetic comparative analysis that found geckos had gained and lost adhesive t... more We published a phylogenetic comparative analysis that found geckos had gained and lost adhesive toepads multiple times over their long evolutionary history (Gamble et al., PLoS One, 7, 2012, e39429). This was consistent with decades of morphological studies showing geckos had evolved adhesive toepads on multiple occasions and that the morphology of geckos with ancestrally padless digits can be distinguished from secondarily padless forms. Recently, Harrington & Reeder (J. Evol. Biol., 30, 2017, 313) reanalysed data from Gamble et al. (PLoS One, 7, 2012, e39429) and found little support for the multiple origins hypothesis. Here, we argue that Harrington and Reeder failed to take morphological evidence into account when devising ancestral state reconstruction models and that these biologically unrealistic models led to erroneous conclusions about the evolution of adhesive toepads in geckos.
A molecular phylogeny of the largely rupicolous geckos of the gekkonid genus Afroedura is present... more A molecular phylogeny of the largely rupicolous geckos of the gekkonid genus Afroedura is presented based on a combination of mitochondrial and nuclear gene sequence data. Previously recognized species groups are only partly recovered, with A. pondolia retrieved as very distantly related to the congeners to which it was previously considered allied. Afroedura hawequensis forms a monotypic group that is sister to all other species, which are allocated to the A. nivaria, A. transvaalica, A. africana, A. multiporis, A. marleyi, and A. langi groups. The taxonomic status of species occurring in the former Transvaal province of South Africa (now Limpopo and Mpumalanga provinces) is reviewed based on morphological and molecular evidence. Afroedura rupestris sp. nov. is described in the A. multiporis group, A. maripi sp. nov., A. pongola sp. nov., and A. rondavelica sp. nov., are described in the A. marleyi group, and A. broadleyi sp. nov., A. granitica sp. nov., A. leoloensis sp. nov., A. pienaari sp. nov., and A. waterbergensis sp. nov. are described in the A. langi group. In addition, A. haackei, A. namaquensis, and A. tirasensis, are all raised to specific status. The description of nine new species highlights Limpopo and Mpumalanga provinces as previously unrecognized centers of diversity for the genus Afroedura. A key to the species of Afroedura is provided.
Osteoderms are bony deposits that form within the dermal layer of skin in vertebrates. Within gec... more Osteoderms are bony deposits that form within the dermal layer of skin in vertebrates. Within geckos, osteoderms are uncommon, only described in Gekko gecko and the genus Tarentola. A previous report of osteoderms in the Afro-Malagasy gekkonid genus Geckolepis has been questioned due to the extreme skin fragility and regional integumentary loss within the group. We re-evaluated the integument anatomy of Geckolepis maculata using µCT scanning, histology, and clearing and staining to verify the presence or absence of osteoderms and, if present, to characterise and compare their morphology to the osteoderms of Gekko gecko and Tarentola, as well as osteoderm diversity within squamates. Osteoderms were confirmed present in Geckolepis maculata; however, these osteoderms are compound, imbricating, squamous elements that are morphologically similar to the dermal ossifications observed in scincids and gerrhosaurids, while G. gecko and Tarentola possess plate-like and granular osteoderms. Our results suggest that osteoderms have independently evolved at least three times within the Gekkota and that epidermal anatomy may be a better predictor of osteoderm morphology than ancestral history. Further research is required to investigate the regenerative capability of Geckolepis osteoderms following skin autotomy.
Bulletin of The Museum of Comparative Zoology, Dec 23, 2021
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
An analysis of morphological and allozyme variation in the Namaqua gecko, Pachydactylus namaquens... more An analysis of morphological and allozyme variation in the Namaqua gecko, Pachydactylus namaquensis from southern Africa is presented. Three separately evolving lineages, well defined by morphology and allozyme variation, are identified. The isolated southern population, occurring on the southern escarpment and Cape Fold Mountains surrounding the western Little Karoo, is named P. kladaroderma sp. nov., and is characterized by a slit-like ear opening, low number of granules bordering the mental (3-6) and mental and adjacent infralabials (5-13), the frequent (79%) occurence of the supralabial entering the nostril, and its drab brown base colouration. A northern population, occurring in southern Namibia and the Richtersveld is named P. haackei sp. nov .. and is characterized by its more rounded or squared ear opening; high number of granules bordering the mental and adjacent infralabials (11-19), the general exclusion of the supralabial from the nostril (only 3.7% entry), and brighter, lighter colouration. It is further differentiated from P. k/adaroderma on the basis of fixed differences at 11 allozyme loci. Both new species differ from P. namaquensis, which is mainly restricted to Little Namaqualand, but is sympatric with P. haackei in the Lower Orange River region, by their more heterogenous dorsal scalation, smaller cloacal spurs, lack of spine-like tubercles on the lateral surfaces of the tail, and more fragile skin. The type locality of P. namaquensis is restricted to 'the vicinity of Springbok, Little Namaqualand, Northern Cape Province, South Africa'.
AsstrRAct. A new species of Sphaerodactylus (Squamata: Gekkota: Sphaerodactylidae) is described f... more AsstrRAct. A new species of Sphaerodactylus (Squamata: Gekkota: Sphaerodactylidae) is described from an amber inclusion from the late Early Miocene or early Middle Miocene (15 to 20 million years ago) of the Dominican Republic. Unlike earlier amber-embedded specimens assigned to this genus, the new specimen is largely skeletal, with some integument remaining. A combination of 258 (of 674) osteological and external characters could be scored for the new species in a cladistic analysis of 21 gekkotan species, including representatives of all sphaerodactylid genera. The most parsimonious trees obtained confirm the placement of the amber gecko within the genus Sphaerodactylus and a comparison with extant Hispaniolan and Puerto Rican congeners suggests phenetic similarity both with members of S. difficilis complex and the S. shrevei species group. Character mapping on the basis of the phylogenetic analysis permits the preliminary identification of morphological characters diagnostic of the Sphaerodactylidae, Sphaerodactylini, and Sphaerodactylus. Osteological features of the new species are discussed in the broader context of sphaerodactyl, sphaerodactylid, and gekkotan variation. Extant Hispaniolan Sphaerodactylus display significant ecomorphological variation and it is likely that the many known, though not yet described, amber-embedded specimens will eventually reveal similar patterns in their Miocene congeners.
Bulletin of The Peabody Museum of Natural History, Apr 1, 2016
In July 2012, 22 people representing eight institutions from six countries conducted a six-day ex... more In July 2012, 22 people representing eight institutions from six countries conducted a six-day expedition to the submontane heath forest near Bukit Pagon in Brunei Darussalam. Base camp was located at an elevation of 862 masl about 200 m from the Brunei-Sarawak border and 9 km from the peak of Bukit Pagon. The herpetology and ichthyology portion of the survey resulted in the collection of 61 specimens, representing 30 species, with 4 additional species documented by photograph but not collected. One additional taxon, Tropidophorus brookei, was seen but neither collected nor photographed. Nearly half of the species found are endemic to Borneo. The findings of this brief expedition shed light on the distribution of many endemic taxa in one of the world's greatest biodiversity hot spots. Despite its small size, Brunei supports a rich vertebrate fauna that is understudied compared with neighboring Sarawak and nearby Sabah.
Zoological Journal of the Linnean Society, Nov 25, 2011
Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Ca... more Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Caribbean. We estimated phylogenetic relationships among sphaerodactyl genera using both separate and combined analyses of seven nuclear genes. Relationships among genera were incongruent at different loci and phylogenies were characterized by short, in some cases zero-length, internal branches and poor phylogenetic support at most nodes. We recovered a polyphyletic Coleodactylus, with Coleodactylus amazonicus being deeply divergent from the remaining Coleodactylus species sampled. The C. amazonicus lineage possessed unique codon deletions in the genes PTPN12 and RBMX while the remaining Coleodactylus species had unique codon deletions in RAG1. Topology tests could not reject a monophyletic Coleodactylus, but we show that short internal branch lengths decreased the accuracy of topology tests because there were not enough data along these short branches to support one phylogenetic hypothesis over another. Morphological data corroborated results of the molecular phylogeny, with Coleodactylus exhibiting substantial morphological heterogeneity. We identified a suite of unique craniofacial features that differentiate C. amazonicus not only from other Coleodactylus species, but also from all other geckos. We describe this novel sphaerodactyl lineage as a new genus, Chatogekko gen. nov. We present a detailed osteology of Chatogekko, characterizing osteological correlates of miniaturization that provide a framework for future studies in sphaerodactyl systematics and biology.
The mourning gecko (Lepidodactylus lugubris) is a nocturnal, parthenogenetic species that has bee... more The mourning gecko (Lepidodactylus lugubris) is a nocturnal, parthenogenetic species that has been introduced in Colombia. Despite more than 70 years of collecting activity in the country, there has yet to be a thorough evaluation of its distribution in Colombia. Here we review all records from eight museum collections, along with literature reports, to generate a locality map documenting this gecko's distribution in space and time. Additionally, new sightings are reported and its range expansion in the Cauca rift valley is discussed.
Phylogenetic relationships among gekkotan lizards were estimated from five nuclear protein-coding... more Phylogenetic relationships among gekkotan lizards were estimated from five nuclear protein-coding genes in separate and combined analyses using maximum parsimony, maximum likelihood and Bayesian analyses. All analyses recovered a monophyletic transAtlantic gecko clade (Phyllodactylidae) consisting of the genera Asaccus, Haemodracon, Homonota, Phyllodactylus, Phyllopezus, Ptyodactylus, Tarentola and Thecadactylus. No other phylogenetic or taxonomic hypotheses have proposed linking these genera, which have been consistently grouped with other taxa outside of the clade. In this paper, we determine the relationships of this new clade to other major gekkotan groups, evaluate previous phylogenetic hypotheses regarding constituent members of this novel clade, and critically examine the use of historically important morphological characters in gekkotan systematics as they relate to this novel clade, specifically-phalangeal formulae, hyoid morphology and external structure of the toepads.
Recent molecular phylogenetic work has found that Breviceps Merrem, 1820 comprises two major clad... more Recent molecular phylogenetic work has found that Breviceps Merrem, 1820 comprises two major clades, one of which, the B. mossambicus group, is widely distributed across southern sub-Saharan Africa. This group is notable for harboring abundant cryptic diversity. Of the four most recently described Breviceps species, three are members of this group, and at least five additional lineages await formal description. Although Breviceps has long been known to occur in Angola, no contemporary material has been collected until recently. The three most widespread taxa, B. adspersus, B. mossambicus, and B. poweri, may all occur in Angola, but accurate species assignment remains challenging given the rampant morphological similarity between these taxa, and, until recently, the lack of genetic resources. Phylogenetic, morphological, and acoustic analyses of recently collected samples from disparate localities within Angola provide evidence for an undescribed species that is sister to B. poweri. The new species can be diagnosed from its sister taxon by lacking pale spots along the flanks, a pale patch above the vent, and a short, dark band below the nares (all present in B. poweri). Additionally, the male advertisement call differs from the three other Breviceps that might occur in Angola in having both a longer interval between consecutive calls and a higher average dominant frequency. We here describe this lineage as a distinct species, currently only known from Angola, and discuss the presence of other Breviceps taxa within Angola.
We use 3100 bp of mitochondrial (ND2, ND4) and nuclear (RAG1, phosducin) DNA sequence data to rec... more We use 3100 bp of mitochondrial (ND2, ND4) and nuclear (RAG1, phosducin) DNA sequence data to recover phylogenetic relationships among 14 of the 16 recognized taxa of the lizard genus Paroedura as well as two undescribed forms. These geckos are endemic to Madagascar and the Comores and are popularly kept and bred by herpetoculturalists. The closest relative of Paroedura is another Indian Ocean leaf-toed gecko, Ebenavia. Both Bayesian inference and maximum parsimony strongly support the monophyly of two major clades within Paroedura that conflict with existing species group assignments based on scale characteristics. Our well-resolved tree elucidates a biogeographic pattern in which eastern Paroedura are most basal and western and southwestern species form a monophyletic group. Our data demonstrate the phylogenetic utility of phosducin, a novel marker in squamate phylogenetics, at the intrageneric level.
Molecular Phylogenetics and Evolution, Sep 1, 2016
Despite an abundance of phylogenetic studies focused on intrageneric relationships of members of ... more Despite an abundance of phylogenetic studies focused on intrageneric relationships of members of the Mabuya group, the intergeneric relationships have remained difficult to resolve. The most-persistent unresolved regions of the phylogeny of the group include: (1) the placement of the Middle-Eastern Trachylepis with respect to the Afro-Malagasy Trachylepis and its taxonomic status; (2) the phylogenetic position of the Cape Verdean Chioninia within the larger Mabuya group; (3) support for the placement of Dasia with respect to the entire group; and (4) the phylogenetic placement of Eutropis novemcarinata with respect to other Eutropis and Dasia. In this study, we include representatives of all these taxa as well as African Eumecia and Neotropical Mabuya. We seek to address these phylogenetic and systematic issues by generating a well-resolved and supported phylogeny for the Mabuya group as a whole that can be used to develop a stable taxonomy and reconstruct the geographic patterns of diversification within the group. To meet these goals, we built a large multi-locus dataset of 11 markers (nine nuclear and two mitochondrial), and performed concatenated and species tree analyses to generate a well-supported phylogeny for the group. Statistical topology tests reject the monophyly of Middle-Eastern Trachylepis with Afro-Malagasy Trachylepis, and to reflect monophyly we place the Middle-Eastern species into a previously described genus, Heremites. Cape-Verdean Chioninia are resolved as the strongly supported sister-group to Afro-Malagasy Trachylepis. Monophyly of the Southeast-Asian genera, Eutropis and Dasia, is not supported, with a clade composed of Dasia+Eutropis novemcarinata more closely related to the rest of the Mabuya group than to the remaining Eutropis. The phylogenetic position of E. novemcarinata renders Eutropis polyphyletic, and we therefore describe and place E. novemcarinata into a new monotypic genus, Toenayar, to preserve monophyly among the genera. In light of these novel findings, we review and discuss the historical biogeography of the entire Mabuya group.
Introduction Geckos (infraorder Gekkota) are among the most prominent and species-rich herpetofau... more Introduction Geckos (infraorder Gekkota) are among the most prominent and species-rich herpetofaunal elements in most parts of the Old World tropics. While Africa, Madagascar, southern Asia and Australia each have endemic gecko radiations, few span multiple ...
This article may be used for research, teaching and private study purposes. Any substantial or sy... more This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan, sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
ABSTRACT In 1831 Sir Andrew Smith described a new genus and species of amphibian, Tremeropugus ty... more ABSTRACT In 1831 Sir Andrew Smith described a new genus and species of amphibian, Tremeropugus typicus, from South Africa. The description, which appeared in the obscure and short‐lived South African Quarterly Journal, has been overlooked for almost 175 years. Tremeropugus A. Smith, 1831 is a subjective junior synonym of Xenopus Wagler, 1827, whilst Tremeropugus typicus is almost certainly a subjective junior synonym of Bufo laevis Daudin, 1802.
We employed nuclear and mitochondrial DNA sequence data to investigate relationships within the g... more We employed nuclear and mitochondrial DNA sequence data to investigate relationships within the gekkonid genus Nactus and between Nactus and other gekkonid genera. Nuclear (RAG-1, PDC) and mitochondrial (ND2) data provide strong support for conflicting patterns of relationship among bisexual New Guinean species of Nactus and the unisexual oceanic form N. pelagicus. This may be explained by an ancient mitochondrial introgression event between N. sphaerodactylodes and N. vankampeni, a recent selective sweep of mitochondrial DNA throughout N. vankampeni, and gene conflict stemming from the hybrid event that gave rise to N. pelagicus. Strong support from all data partitions is obtained for the sister group relationship of Nactus to a clade consisting of the Australian Heteronotia and the Southeast Asian Dixonius. Putative synapomorphies of the Nactus/Heteronotia/Dixonius clade include the reduction of the second phalanx of digit IV of the manus and the presence of regular rows of keeled (sometimes multicarinate) dorsal tubercles on the dorsum. Nactus and Heteronotia both include parthenogenetic species formed via hybridogenesis. This is rare among geckos, and vertebrates in general, and at some level may also be synapomorphic. Dixonius is not known to have any all-female species, but "D. siamensis" consists of multiple chromosome "races" that mirror morphologically cryptic, but karyotypically distinct, species in the other two genera. The strong support for the Nactus/Heteronotia/Dixonius clade demonstrates that the leaf-toed digital morphology of Dixonius has evolved multiple times within the Gekkonidae and suggests that superficial digital morphology may be misleading with respect to gekkonid suprageneric relationships.
Journal of Zoological Systematics and Evolutionary Research, Sep 26, 2012
ABSTRACT The Miocene gecko in amber, Sphaerodactylus dommeli, is one of the best-preserved fossil... more ABSTRACT The Miocene gecko in amber, Sphaerodactylus dommeli, is one of the best-preserved fossil gekkotan species; nonetheless, its identity has been ques-tioned and it has been insinuated to be an iguanian referable to the mega-diverse genus Anolis. In this paper, we provide digital X‐rays and new osteo-logical evidence that include 11 characters that reaffirms its placement within the infraorder Gekkota and eight characters that specifically place this fossil within the species-rich genus Sphaerodactylus, in which it was originally described. This contribution seeks to eliminate remaining scepticism about the generic allocation of this species, and to provide a reliable calibration point for ongoing research in squamate phylogenetics, especially for biogeographical studies and molecular dating inference. This contribution also reviews many diagnostic characters for the two genera in question, which is critical for the correct identification of amber-embedded specimens representing the rich Hispaniolan lizard paleocommunity.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, Dec 27, 2017
Well-resolved phylogenetic hypotheses and ontogenetic data are often necessary for investigating ... more Well-resolved phylogenetic hypotheses and ontogenetic data are often necessary for investigating the evolution of structural novelty. The Sphaerodactylidae comprises 12 genera of predominantly miniaturized geckos. The genera Aristelliger and Teratoscincus are exceptions, with taxa reaching snout-to-vent lengths far exceeding those of other sphaerodactylids. These two genera possess enigmatic, supraorbital ossifications-parafrontal bones-which are encountered nowhere else among squamates. At the time of their discovery, these structures were believed to be the result of evolutionary convergence. Although relationships between other sphaerodactylids remain unresolved, recent molecular and morphological data have supported a close relationship between Aristelliger and Teratoscincus. We investigated the ontogeny of parafrontal bones to better understand relationships between sphaerodactylid body size and the presence of parafrontals, and to evaluate whether ontogenetic data support the homology of parafrontals between Aristelliger and Teratoscincus. We hypothesize that the parafrontals of Aristelliger and Teratoscincus are homologous and that there is a threshold body size in sphaerodactylids below which parafrontals do not develop, thus explaining their absence from the miniaturized taxa. The presence of parafrontals was investigated in all sphaerodactylid genera using cleared-andstained, radiographed, and skeletonized specimens. Total surface area of parafrontals was measured for seven species of Aristelliger and six species of Teratoscincus throughout their ontogeny. Histology was used to investigate the cellular composition of the parafrontals throughout their ontogeny. Our data suggest that parafrontals have evolved in parallel from a homologous, parafrontal precursor and that the onset of parafrontal development is not strictly dependent on a threshold body size.
... Gekkonidae) revisited: new insights from a molecular phylogeny ELI GREENBAUM, AARON M. BAUER ... more ... Gekkonidae) revisited: new insights from a molecular phylogeny ELI GREENBAUM, AARON M. BAUER AND TODD R. JACKMAN Department of Biology, Villanova University, 800 Lancaster Ave., Villanova, PA 19085, USA [email protected] ...
We published a phylogenetic comparative analysis that found geckos had gained and lost adhesive t... more We published a phylogenetic comparative analysis that found geckos had gained and lost adhesive toepads multiple times over their long evolutionary history (Gamble et al., PLoS One, 7, 2012, e39429). This was consistent with decades of morphological studies showing geckos had evolved adhesive toepads on multiple occasions and that the morphology of geckos with ancestrally padless digits can be distinguished from secondarily padless forms. Recently, Harrington & Reeder (J. Evol. Biol., 30, 2017, 313) reanalysed data from Gamble et al. (PLoS One, 7, 2012, e39429) and found little support for the multiple origins hypothesis. Here, we argue that Harrington and Reeder failed to take morphological evidence into account when devising ancestral state reconstruction models and that these biologically unrealistic models led to erroneous conclusions about the evolution of adhesive toepads in geckos.
A molecular phylogeny of the largely rupicolous geckos of the gekkonid genus Afroedura is present... more A molecular phylogeny of the largely rupicolous geckos of the gekkonid genus Afroedura is presented based on a combination of mitochondrial and nuclear gene sequence data. Previously recognized species groups are only partly recovered, with A. pondolia retrieved as very distantly related to the congeners to which it was previously considered allied. Afroedura hawequensis forms a monotypic group that is sister to all other species, which are allocated to the A. nivaria, A. transvaalica, A. africana, A. multiporis, A. marleyi, and A. langi groups. The taxonomic status of species occurring in the former Transvaal province of South Africa (now Limpopo and Mpumalanga provinces) is reviewed based on morphological and molecular evidence. Afroedura rupestris sp. nov. is described in the A. multiporis group, A. maripi sp. nov., A. pongola sp. nov., and A. rondavelica sp. nov., are described in the A. marleyi group, and A. broadleyi sp. nov., A. granitica sp. nov., A. leoloensis sp. nov., A. pienaari sp. nov., and A. waterbergensis sp. nov. are described in the A. langi group. In addition, A. haackei, A. namaquensis, and A. tirasensis, are all raised to specific status. The description of nine new species highlights Limpopo and Mpumalanga provinces as previously unrecognized centers of diversity for the genus Afroedura. A key to the species of Afroedura is provided.
Osteoderms are bony deposits that form within the dermal layer of skin in vertebrates. Within gec... more Osteoderms are bony deposits that form within the dermal layer of skin in vertebrates. Within geckos, osteoderms are uncommon, only described in Gekko gecko and the genus Tarentola. A previous report of osteoderms in the Afro-Malagasy gekkonid genus Geckolepis has been questioned due to the extreme skin fragility and regional integumentary loss within the group. We re-evaluated the integument anatomy of Geckolepis maculata using µCT scanning, histology, and clearing and staining to verify the presence or absence of osteoderms and, if present, to characterise and compare their morphology to the osteoderms of Gekko gecko and Tarentola, as well as osteoderm diversity within squamates. Osteoderms were confirmed present in Geckolepis maculata; however, these osteoderms are compound, imbricating, squamous elements that are morphologically similar to the dermal ossifications observed in scincids and gerrhosaurids, while G. gecko and Tarentola possess plate-like and granular osteoderms. Our results suggest that osteoderms have independently evolved at least three times within the Gekkota and that epidermal anatomy may be a better predictor of osteoderm morphology than ancestral history. Further research is required to investigate the regenerative capability of Geckolepis osteoderms following skin autotomy.
Bulletin of The Museum of Comparative Zoology, Dec 23, 2021
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
An analysis of morphological and allozyme variation in the Namaqua gecko, Pachydactylus namaquens... more An analysis of morphological and allozyme variation in the Namaqua gecko, Pachydactylus namaquensis from southern Africa is presented. Three separately evolving lineages, well defined by morphology and allozyme variation, are identified. The isolated southern population, occurring on the southern escarpment and Cape Fold Mountains surrounding the western Little Karoo, is named P. kladaroderma sp. nov., and is characterized by a slit-like ear opening, low number of granules bordering the mental (3-6) and mental and adjacent infralabials (5-13), the frequent (79%) occurence of the supralabial entering the nostril, and its drab brown base colouration. A northern population, occurring in southern Namibia and the Richtersveld is named P. haackei sp. nov .. and is characterized by its more rounded or squared ear opening; high number of granules bordering the mental and adjacent infralabials (11-19), the general exclusion of the supralabial from the nostril (only 3.7% entry), and brighter, lighter colouration. It is further differentiated from P. k/adaroderma on the basis of fixed differences at 11 allozyme loci. Both new species differ from P. namaquensis, which is mainly restricted to Little Namaqualand, but is sympatric with P. haackei in the Lower Orange River region, by their more heterogenous dorsal scalation, smaller cloacal spurs, lack of spine-like tubercles on the lateral surfaces of the tail, and more fragile skin. The type locality of P. namaquensis is restricted to 'the vicinity of Springbok, Little Namaqualand, Northern Cape Province, South Africa'.
AsstrRAct. A new species of Sphaerodactylus (Squamata: Gekkota: Sphaerodactylidae) is described f... more AsstrRAct. A new species of Sphaerodactylus (Squamata: Gekkota: Sphaerodactylidae) is described from an amber inclusion from the late Early Miocene or early Middle Miocene (15 to 20 million years ago) of the Dominican Republic. Unlike earlier amber-embedded specimens assigned to this genus, the new specimen is largely skeletal, with some integument remaining. A combination of 258 (of 674) osteological and external characters could be scored for the new species in a cladistic analysis of 21 gekkotan species, including representatives of all sphaerodactylid genera. The most parsimonious trees obtained confirm the placement of the amber gecko within the genus Sphaerodactylus and a comparison with extant Hispaniolan and Puerto Rican congeners suggests phenetic similarity both with members of S. difficilis complex and the S. shrevei species group. Character mapping on the basis of the phylogenetic analysis permits the preliminary identification of morphological characters diagnostic of the Sphaerodactylidae, Sphaerodactylini, and Sphaerodactylus. Osteological features of the new species are discussed in the broader context of sphaerodactyl, sphaerodactylid, and gekkotan variation. Extant Hispaniolan Sphaerodactylus display significant ecomorphological variation and it is likely that the many known, though not yet described, amber-embedded specimens will eventually reveal similar patterns in their Miocene congeners.
Bulletin of The Peabody Museum of Natural History, Apr 1, 2016
In July 2012, 22 people representing eight institutions from six countries conducted a six-day ex... more In July 2012, 22 people representing eight institutions from six countries conducted a six-day expedition to the submontane heath forest near Bukit Pagon in Brunei Darussalam. Base camp was located at an elevation of 862 masl about 200 m from the Brunei-Sarawak border and 9 km from the peak of Bukit Pagon. The herpetology and ichthyology portion of the survey resulted in the collection of 61 specimens, representing 30 species, with 4 additional species documented by photograph but not collected. One additional taxon, Tropidophorus brookei, was seen but neither collected nor photographed. Nearly half of the species found are endemic to Borneo. The findings of this brief expedition shed light on the distribution of many endemic taxa in one of the world's greatest biodiversity hot spots. Despite its small size, Brunei supports a rich vertebrate fauna that is understudied compared with neighboring Sarawak and nearby Sabah.
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