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1.
Proc Natl Acad Sci U S A ; 119(29): e2121036119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858351

RESUMO

Many processes of biological diversification can simultaneously affect multiple evolutionary lineages. Examples include multiple members of a gene family diverging when a region of a chromosome is duplicated, multiple viral strains diverging at a "super-spreading" event, and a geological event fragmenting whole communities of species. It is difficult to test for patterns of shared divergences predicted by such processes because all phylogenetic methods assume that lineages diverge independently. We introduce a Bayesian phylogenetic approach to relax the assumption of independent, bifurcating divergences by expanding the space of topologies to include trees with shared and multifurcating divergences. This allows us to jointly infer phylogenetic relationships, divergence times, and patterns of divergences predicted by processes of diversification that affect multiple evolutionary lineages simultaneously or lead to more than two descendant lineages. Using simulations, we find that the method accurately infers shared and multifurcating divergence events when they occur and performs as well as current phylogenetic methods when divergences are independent and bifurcating. We apply our approach to genomic data from two genera of geckos from across the Philippines to test if past changes to the islands' landscape caused bursts of speciation. Unlike previous analyses restricted to only pairs of gecko populations, we find evidence for patterns of shared divergences. By generalizing the space of phylogenetic trees in a way that is independent from the likelihood model, our approach opens many avenues for future research into processes of diversification across the life sciences.


Assuntos
Biodiversidade , Lagartos , Filogenia , Animais , Teorema de Bayes , Genoma , Lagartos/classificação , Lagartos/genética
2.
Syst Biol ; 71(1): 40-57, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33964168

RESUMO

In cryptic amphibian complexes, there is a growing trend to equate high levels of genetic structure with hidden cryptic species diversity. Typically, phylogenetic structure and distance-based approaches are used to demonstrate the distinctness of clades and justify the recognition of new cryptic species. However, this approach does not account for gene flow, spatial, and environmental processes that can obfuscate phylogenetic inference and bias species delimitation. As a case study, we sequenced genome-wide exons and introns to evince the processes that underlie the diversification of Philippine Puddle Frogs-a group that is widespread, phenotypically conserved, and exhibits high levels of geographically based genetic structure. We showed that widely adopted tree- and distance-based approaches inferred up to 20 species, compared to genomic analyses that inferred an optimal number of five distinct genetic groups. Using a suite of clustering, admixture, and phylogenetic network analyses, we demonstrate extensive admixture among the five groups and elucidate two specific ways in which gene flow can cause overestimations of species diversity: 1) admixed populations can be inferred as distinct lineages characterized by long branches in phylograms; and 2) admixed lineages can appear to be genetically divergent, even from their parental populations when simple measures of genetic distance are used. We demonstrate that the relationship between mitochondrial and genome-wide nuclear $p$-distances is decoupled in admixed clades, leading to erroneous estimates of genetic distances and, consequently, species diversity. Additionally, genetic distance was also biased by spatial and environmental processes. Overall, we showed that high levels of genetic diversity in Philippine Puddle Frogs predominantly comprise metapopulation lineages that arose through complex patterns of admixture, isolation-by-distance, and isolation-by-environment as opposed to species divergence. Our findings suggest that speciation may not be the major process underlying the high levels of hidden diversity observed in many taxonomic groups and that widely adopted tree- and distance-based methods overestimate species diversity in the presence of gene flow. [Cryptic species; gene flow; introgression; isolation-by-distance; isolation-by-environment; phylogenetic network; species delimitation.].


Assuntos
DNA Mitocondrial , Fluxo Gênico , Animais , Anuros/genética , DNA Mitocondrial/genética , Variação Genética , Filipinas , Filogenia
3.
Proc Biol Sci ; 287(1940): 20202102, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33290680

RESUMO

Genome-scale data have greatly facilitated the resolution of recalcitrant nodes that Sanger-based datasets have been unable to resolve. However, phylogenomic studies continue to use traditional methods such as bootstrapping to estimate branch support; and high bootstrap values are still interpreted as providing strong support for the correct topology. Furthermore, relatively little attention has been given to assessing discordances between gene and species trees, and the underlying processes that produce phylogenetic conflict. We generated novel genomic datasets to characterize and determine the causes of discordance in Old World treefrogs (Family: Rhacophoridae)-a group that is fraught with conflicting and poorly supported topologies among major clades. Additionally, a suite of data filtering strategies and analytical methods were applied to assess their impact on phylogenetic inference. We showed that incomplete lineage sorting was detected at all nodes that exhibited high levels of discordance. Those nodes were also associated with extremely short internal branches. We also clearly demonstrate that bootstrap values do not reflect uncertainty or confidence for the correct topology and, hence, should not be used as a measure of branch support in phylogenomic datasets. Overall, we showed that phylogenetic discordances in Old World treefrogs resulted from incomplete lineage sorting and that species tree inference can be improved using a multi-faceted, total-evidence approach, which uses the most amount of data and considers results from different analytical methods and datasets.


Assuntos
Anuros/fisiologia , Filogenia , Animais , Genômica
4.
Mol Ecol ; 29(20): 3970-3987, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32808335

RESUMO

Most new cryptic species are described using conventional tree- and distance-based species delimitation methods (SDMs), which rely on phylogenetic arrangements and measures of genetic divergence. However, although numerous factors such as population structure and gene flow are known to confound phylogenetic inference and species delimitation, the influence of these processes is not frequently evaluated. Using large numbers of exons, introns, and ultraconserved elements obtained using the FrogCap sequence-capture protocol, we compared conventional SDMs with more robust genomic analyses that assess population structure and gene flow to characterize species boundaries in a Southeast Asian frog complex (Pulchrana picturata). Our results showed that gene flow and introgression can produce phylogenetic patterns and levels of divergence that resemble distinct species (up to 10% divergence in mitochondrial DNA). Hybrid populations were inferred as independent (singleton) clades that were highly divergent from adjacent populations (7%-10%) and unusually similar (<3%) to allopatric populations. Such anomalous patterns are not uncommon in Southeast Asian amphibians, which brings into question whether the high levels of cryptic diversity observed in other amphibian groups reflect distinct cryptic species-or, instead, highly admixed and structured metapopulation lineages. Our results also provide an alternative explanation to the conundrum of divergent (sometimes nonsister) sympatric lineages-a pattern that has been celebrated as indicative of true cryptic speciation. Based on these findings, we recommend that species delimitation of continuously distributed "cryptic" groups should not rely solely on conventional SDMs, but should necessarily examine population structure and gene flow to avoid taxonomic inflation.


Assuntos
Fluxo Gênico , Especiação Genética , Animais , Anuros/genética , Teorema de Bayes , DNA Mitocondrial/genética , Filogenia
5.
Mol Phylogenet Evol ; 151: 106899, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32590046

RESUMO

Using FrogCap, a recently-developed sequence-capture protocol, we obtained >12,000 highly informative exons, introns, and ultraconserved elements (UCEs), which we used to illustrate variation in evolutionary histories of these classes of markers, and to resolve long-standing systematic problems in Southeast Asian Golden-backed frogs of the genus-complex Hylarana. We also performed a comprehensive suite of analyses to assess the relative performance of different genetic markers, data filtering strategies, tree inference methods, and different measures of branch support. To reduce gene tree estimation error, we filtered the data using different thresholds of taxon completeness (missing data) and parsimony informative sites (PIS). We then estimated species trees using concatenated datasets and Maximum Likelihood (IQ-TREE) in addition to summary (ASTRAL-III), distance-based (ASTRID), and site-based (SVDQuartets) multispecies coalescent methods. Topological congruence and branch support were examined using traditional bootstrap, local posterior probabilities, gene concordance factors, quartet frequencies, and quartet scores. Our results did not yield a single concordant topology. Instead, introns, exons, and UCEs clearly possessed different phylogenetic signals, resulting in conflicting, yet strongly-supported phylogenetic estimates. However, a combined analysis comprising the most informative introns, exons, and UCEs converged on a similar topology across all analyses, with the exception of SVDQuartets. Bootstrap values were consistently high despite high levels of incongruence and high proportions of gene trees supporting conflicting topologies. Although low bootstrap values did indicate low heuristic support, high bootstrap support did not necessarily reflect congruence or support for the correct topology. This study reiterates findings of some previous studies, which demonstrated that traditional bootstrap values can produce positively misleading measures of support in large phylogenomic datasets. We also showed a remarkably strong positive relationship between branch length and topological congruence across all datasets, implying that very short internodes remain a challenge to resolve, even with orders of magnitude more data than ever before. Overall, our results demonstrate that more data from unfiltered or combined datasets produced superior results. Although data filtering reduced gene tree incongruence, decreased amounts of data also biased phylogenetic estimation. A point of diminishing returns was evident, at which higher congruence (from more stringent filtering) at the expense of amount of data led to topological error as assessed by comparison to more complete datasets across different genomic markers. Additionally, we showed that applying a parameter-rich model to a partitioned analysis of concatenated data produces better results compared to unpartitioned, or even partitioned analysis using model selection. Despite some lingering uncertainties, a combined analysis of our genomic data and sequences supplemented from GenBank (on the basis of a few gene regions) revealed highly supported novel systematic arrangements. Based on these new findings, we transfer Amnirana nicobariensis into the genus Indosylvirana; and I. milleti and Hylarana celebensis to the genus Papurana. We also provisionally place H. attigua in the genus Papurana pending verification from positively identified (voucher substantiated) samples.


Assuntos
Anuros/classificação , Anuros/genética , Sequência Conservada/genética , Bases de Dados Genéticas , Éxons/genética , Íntrons/genética , Filogenia , Animais , Funções Verossimilhança , RNA Ribossômico 16S/genética , Especificidade da Espécie
6.
Mol Phylogenet Evol ; 150: 106861, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32497832

RESUMO

Southeast Asia hosts a rich concentration of biodiversity within multiple biodiversity hotspots. Indochina, a region with remarkably high levels of in situ diversification, possesses five major rivers (Ayeyarwady, Chiang Mai, Mekong, Red, and Salween), several of which coincide with phylogenetic breaks of terrestrial taxa. Draco maculatus possesses a range that stretches across Indochina, which widespread geographic distribution along with potential discrete variation within subspecies alludes to the possibility of this taxon constituting multiple divergent lineages. Using sequence data from three mitochondrial (12S, 16S, and ND2) and three nuclear (BDNF, CMOS, and PNN) genes, we provide the first estimated phylogeny of this hypothesized species complex and examine its phylogeographic architecture with maximum likelihood and Bayes factor delimitation (BFD) approaches. Our results support multiple divergent lineages with phylogenetic breaks coincident with rivers, indicating that river barriers may be contributing to the elevated levels of in situ diversification of Indochina.


Assuntos
Lagartos/classificação , Animais , Teorema de Bayes , Biodiversidade , Fator Neurotrófico Derivado do Encéfalo/classificação , Fator Neurotrófico Derivado do Encéfalo/genética , Indochina , Lagartos/genética , Mitocôndrias/genética , NADH Desidrogenase/classificação , NADH Desidrogenase/genética , Filogenia , Filogeografia , Subunidades Proteicas/classificação , Subunidades Proteicas/genética , RNA Ribossômico/classificação , RNA Ribossômico/genética
7.
Mol Phylogenet Evol ; 146: 106731, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31904508

RESUMO

Recent phylogenetic studies of gekkonid lizards have revealed unexpected, widespread paraphyly and polyphyly among genera, unclear generic boundaries, and a tendency towards the nesting of taxa exhibiting specialized, apomorphic morphologies within geographically widespread "generalist" clades. This is especially true in Australasia, where monophyly of Gekko proper has been questioned with respect to phenotypically ornate flap-legged geckos of the genus Luperosaurus, the Philippine false geckos of the genus Pseudogekko, and even the elaborately "derived" parachute geckos of the genus Ptychozoon. Here we employ sequence capture targeting 5060 ultraconserved elements (UCEs) to infer phylogenomic relationships among 42 representative ingroup gekkonine lizard taxa. We analyze multiple datasets of varying degrees of completeness (10, 50, 75, 95, and 100 percent complete with 4715, 4051, 3376, 2366, and 772 UCEs, respectively) using concatenated maximum likelihood and multispecies coalescent methods. Our sampling scheme addresses four persistent systematic questions in this group: (1) Are Luperosaurus and Ptychozoon monophyletic, and are any of these named species truly nested within Gekko? (2) Are prior phylogenetic estimates of Sulawesi's L. iskandari as the sister taxon to Melanesian G. vittatus supported by our genome-scale dataset? (3) Is the high-elevation L. gulat of Palawan Island correctly placed within Gekko? (4) And, finally, where do the enigmatic taxa P. rhacophorus and L. browni fall in a higher-level gekkonid phylogeny? We resolve these issues; confirm with strong support some previously inferred findings (placement of Ptychozoon taxa within Gekko; the sister taxon relationship between L. iskandari and G. vittatus); resolve the systematic position of unplaced taxa (L. gulat, and L. browni); and transfer L. iskandari, L. gulat, L. browni, and all members of the genus Ptychozoon to the genus Gekko. Our unexpected and novel systematic inference of the placement of Ptychozoon rhacophorus suggests that this species is not grouped with Ptychozoon or even Luperosaurus (as previously expected) but may, in fact, be most closely related to several Indochinese species of Gekko. With our resolved and strongly supported phylogeny, we present a new classification emphasizing the most inclusive, original generic name (Gekko) for these ~60 taxa, arranged into seven subgenera.


Assuntos
Lagartos/classificação , Animais , Australásia , Sequência de Bases , Sequência Conservada , Genômica , Indonésia , Lagartos/genética , Filogenia , Análise de Sequência de DNA
9.
Mol Phylogenet Evol ; 74: 29-37, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24486878

RESUMO

We utilize robust geographical genetic sampling, a multilocus dataset, a new synthesis of numerous fossil calibration points, a time-calibrated phylogeny, and the Dispersal-Extinction-Cladogenesis model to test the prediction that widespread Southeast Asian water monitor species initially diversified on the Asian mainland and subsequently invaded the island archipelagos of the Philippines, Sundaland, and Wallacea. Our results strongly contradict these expectations and instead infer an initial water monitor radiation of range-restricted but highly divergent evolutionary lineages (now recognized as endemic species) in one archipelago around 3.6 mya, followed by an out-of-the-Philippines reinvasion of the mainland (2.2 mya), resulting in a few, widespread species that now inhabit most the islands of the Sunda Shelf and the Southeast Asian mainland as far north as Myanmar, as well as an out-of-the-Philippines invasion of Sulawesi (2.1 mya). Our analyses both confirm the importance of island archipelagos as drivers of diversification for mainland biodiversity and emphasize the global evolutionary significance and conservation priority of the Philippines for understanding processes of diversification in island archipelagos.


Assuntos
Fósseis , Lagartos/genética , Filogenia , Animais , Sudeste Asiático , Biodiversidade , Calibragem
10.
Zootaxa ; 3760: 67-78, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24870072

RESUMO

A new species of gekkonid, Hemiphyllodactylus chiangmaiensis sp. nov., from northwestern Thailand is separated from all other species of Hemiphyllodactylus by a set of features including: a maximum SVL of 41.2 mm; 8-12 chin scales extending transversely from unions of second and third infralabials and posterior margin of mental; lamellar formula on hand 3-3-3-3 or 3-4-3-3; lamellar formula on foot 3-3-3-3 or 3-4-4-4; continuous precloacal and femoral pores; a unique dorsal color pattern; and caecum and oviducts pigmented. These characters place this species in the speciose H. typus group. Hemiphyllodactylus chiangmaiensis sp. nov. fills a biogeographical hiatus in the distribution of this genus across northern Indochina.


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Feminino , Lagartos/genética , Lagartos/fisiologia , Masculino , Filogenia , Especificidade da Espécie , Tailândia
11.
Zootaxa ; 3795: 45-60, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24870457

RESUMO

A new species of skink in the genus Caledoniscincus is described from the far north-west region of New Caledonia. It is known from a single location, the isolated ultramafic massif of Dôme de Tiébaghi, north of Koumac. The new species, Caledoniscincus pelletieri sp. nov., has a bold, white mid-lateral stripe on the body, a feature which distinguishes it from most other species of Caledoniscincus except the regionally sympatric Caledoniscincus haplorhinus (Günther) and Caledoniscincus austrocaledonicus (Bavay), and the recently described Caledoniscincus constellatus Sadlier, Whitaker, Wood & Bauer just to the south. The new species can be distinguished from these taxa in features of scalation and colouration, most notably in lacking an extension of the pale midlateral stripe between the ear and forelimbs and in having more lamellae on the underside of the fourth toe. The differences in morphology between C. pelletieri sp. nov. and the other members of the genus are complemented by a high level of genetic differentiation, further supporting its distinctiveness as an independent evolutionary lineage warranting recognition as a distinct species. The DNA sequence data for the ND2 mitochondrial gene identifies the new species as the sister to C. constellatus and these two taxa as the sister to all Caledoniscincus. The species is of extremely high conservation concern given its restricted distribution in an area that is currently being heavily impacted by human activities, and it satisfies the IUCN criteria to be ranked as a Critically Endangered species.


Assuntos
Lagartos/anatomia & histologia , Animais , Ecossistema , Espécies em Perigo de Extinção , Feminino , Lagartos/genética , Masculino , Nova Caledônia , Filogenia
12.
Zootaxa ; 3755: 434-46, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24869831

RESUMO

A new species of Bent-toed Gecko Cyrtodactylus guakanthanensis sp. nov. of the C. sworderi complex is described from a limestone forest in Perak, Peninsular Malaysia whose karst formations at the type locality are within an active quarry. Cyrtodactylus guakanthanensis sp. nov. can be distinguished from all other Sundaland species by having the following suite of character states: adult SVL 77.7-82.2 mm; moderately sized, conical, weakly keeled, body tubercles; tubercles present on occiput, nape, and limbs, and extend posteriorly beyond base of tail; 37-44 ventral scales; no transversely enlarged, median, subcaudal scales; proximal subdigital lamellae transversely expanded; 19-21 subdigital lamellae on fourth toe; abrupt transition between posterior and ventral femoral scales; enlarged femoral scales; no femoral or precloacal pores; precloacal groove absent; wide, dark postorbital stripes from each eye extending posteriorly to the anterior margin of the shoulder region thence forming a transverse band across the anterior margin of the shoulder region; and body bearing five (rarely four) wide, bold, dark bands. Destruction of the karst microhabitat and surrounding limestone forest will extirpate this new species from the type locality and perhaps drive it to complete extinction given that it appears to be restricted to the particular microhabitat structure of the type locality and is not widely distributed throughout the karst formations. As with plants and invertebrates, limestone forests are proving to be significant areas of high herpetological endemism and should be afforded special conservation status rather than turned into cement.


Assuntos
Adaptação Fisiológica/fisiologia , Ecossistema , Lagartos/anatomia & histologia , Lagartos/classificação , Árvores , Animais , Demografia , Lagartos/genética , Lagartos/fisiologia , Malásia , Masculino , Filogenia , Especificidade da Espécie
13.
Zootaxa ; 3774: 381-94, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24871508

RESUMO

Cyrtodactylus metropolis sp. nov. from Batu Caves massif, Selangor, Peninsular Malaysia is differentiated from all congeners by having a unique suite of morphological and color pattern characteristics. Remarkably, this species has been overlooked despite a plethora of field studies at Batu Caves from 1898 to the present and no specimens had ever been examined until now. As with all other limestone forest-adapted Cyrtodactylus in Peninsular Malaysia, C. metropolis sp. nov. is not a cave-adapted species but is far more common on the exterior surfaces of the Batu Caves limestone massif and its surrounding limestone vegetation. We suggest that researchers devote time exploring the exterior surfaces of limestone massifs as well the interiors of their caves.


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Cavernas , Ecossistema , Feminino , Malásia , Masculino
14.
Zootaxa ; (3815): 51-67, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24943599

RESUMO

A newly discovered, diminutive, cave-dwelling, lowland species of the colubrid snake genus Lycodon Boie is described from a limestone cave along the Thai-Malaysian border in the state of Perlis, northwestern Peninsular Malaysia. Lycodon cavernicolus sp. nov. is most closely related to L. butleri Boulenger, an endemic, upland, forest-dwelling species from Peninsular Malaysia of the fasciatus group but is separated from L. butleri and all other species of the L. fasciatus group and the closely related L. ruhstrati group by having the combination of 245 (male) and 232 (female) ventral scales; 113 (male) and 92 (female) paired, subcaudal scales; a single precloacal plate; nine or 10 supralabials; 10 or 11 infralabials; a maximum total length of 508 mm (female); a relative tail length of 0.25-0.27; an immaculate venter in juveniles and dark-brown, posterior, ventral scale margins in adults; and dorsal and caudal bands in juveniles white. The discovery of L. cavernicolus sp. nov. adds to a rapidly growing list of newly discovered reptiles from karst regions and limestone forests of Peninsular Malaysia, underscoring the fact that these areas should be studied before they are quarried as they harbor a significant portion of the Peninsular Malaysia's herpetological diversity.


Assuntos
Colubridae/classificação , Animais , Cavernas , Colubridae/anatomia & histologia , Colubridae/genética , Ecossistema , Feminino , Malásia , Masculino , Dados de Sequência Molecular , Filogenia , Proteínas de Répteis/genética
15.
Zootaxa ; 3764: 427-40, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24870645

RESUMO

A new species of Ansonia is described based on genetic and morphological differentiation. Ansonia lumut sp. nov. is most closely related to three other Peninsular Malaysian species, A. penangensis, A. malayana, and A. jeetsukumarani but differs from these and other congeners by at least 6.9% sequence divergence at the 12S, 16S rRNA and t-RNA-val genes and the following combination of morphological characters: (1) SVL 21.0-23.6 mm in males, 27.7-31.6 mm in females; (2) first finger shorter than second; (3) interorbital and tarsal ridges absent; (4) light interscapular spot absent; (5) presence of large, yellow rictal tubercle; (6) dorsum black with greenish-yellow reticulations; (7) flanks with small yellow spots; (8) fore and hind limbs with yellow cross-bars; and (9) venter light gray with fine, white spotting.


Assuntos
Bufonidae/classificação , Proteínas de Anfíbios/genética , Animais , Bufonidae/anatomia & histologia , Bufonidae/genética , Evolução Molecular , Feminino , Malásia , Masculino , Dados de Sequência Molecular , Filogenia
16.
Zootaxa ; 3786: 359-81, 2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-24869541

RESUMO

An integrative taxonomic analysis of three newly discovered populations of the gekkonid genus Cyrtodactylus Gray from Merapoh, Pahang; Gunung Stong, Kelantan; and Gunung Tebu, Terengganu indicate they are part of the C. pulchellus complex and each is a new species and thusly named Cyrtodactylus sharkari sp. nov., C. jelawangensis sp. nov., and C. timur sp. nov., respectively. Each species bears a unique suite of morphological and color pattern characters separating them from each other and all other nominal species in the C. pulchellus complex. Their phylogenetic relationships to each other and other species in the C. pulchellus complex were unexpected in that they are not in accordance with the general distribution of the species in this complex, underscoring the intricate historical biogeography of the Thai-Malay Peninsula. These descriptions highlight our current lack of knowledge concerning the herpetological diversity and distribution of species in northeastern Peninsular Malaysia.


Assuntos
Lagartos/classificação , Lagartos/genética , Filogenia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Ecossistema , Feminino , Lagartos/anatomia & histologia , Malásia , Masculino , Dados de Sequência Molecular
17.
Zootaxa ; 3691: 538-58, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26167602

RESUMO

A new species of lowland karst dwelling Cnemaspis Strauch 1887, C. grismeri sp. nov. is described from the southeastern base of the Banjaran Bintang in northern Peninsular Malaysia. It is differentiated from its congeners by a unique combination of characters including size, coloration and scalation. Cnemapis grismeri sp. nov. is most closely related to C. mcguirei, an upland species endemic to the Banjaran Bintang. This phylogeographic pattern is also seen in the upland and lowland Banjaran Bintang species of Cyrtodactylus bintangtinggi and C. bintangrendah, respectively (Grismer et al. 2012). The discovery of yet another endemic gekkonid in the poorly explored karst regions of Peninsular Malaysia underscores the necessity for concentrated collecting efforts in these unique landscapes.


Assuntos
Lagartos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Lagartos/anatomia & histologia , Lagartos/crescimento & desenvolvimento , Malásia , Masculino , Tamanho do Órgão
18.
Zootaxa ; 3694: 501-24, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26312308

RESUMO

A new species of skink, Caledoniscincus notialis sp. nov., is described from the ultramafic ranges in southern New Caledonia. It is most similar to, and has previously been referred to Caledoniscincus atropunctatus (Roux), a species with a widespread distribution throughout the Grand Terre and Loyalty Islands. The new species is distinct genetically from all other Caledoniscincus and can be distinguished by a unique pattern of dorsal coloration in males. Its range extends over much of the extensive ultramafic block in the south of the island, including the Goro Plateau and the mountain ranges at the southern edge of the Chaine Centrale north to Mt. Humboldt. It occurs mainly in humid forest habitat, much of which is now present only as isolated fragments in southern New Caledonia. Its preference for a habitat that has undergone a significant reduction in area of extent in a region under pressure from a range of anthropogenic threats suggests this new species is of conservation concern, and could be ranked as Vulnerable under IUCN listing. The genetic relationships of a redefined Caledoniscincus atropunctatus identifies two major subgroups, one located mainly in the northern and central-east regions of Grand Terre and the other in the southern and central-west regions and also including the population on the Loyalty Islands.


Assuntos
Lagartos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Lagartos/anatomia & histologia , Lagartos/genética , Lagartos/crescimento & desenvolvimento , Masculino , Nova Caledônia , Tamanho do Órgão , Filogenia
19.
Zootaxa ; 3616: 239-52, 2013 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24758805

RESUMO

Molecular and morphological analyses indicate that a new upland species of the Cyrtodactylus sworderi complex, C. tebuensis sp. nov. from Gunung Tebu, Terengganu, Malaysia is most closely related to C. sworderi and together they form the sister lineage to C. quadrivirgatus. Cyrtodactylus tebuensis sp. nov. is differentiated from all other species of Sundaland Cyrtodactylus on the basis of having the unique combination of large, conical, keeled body tubercles; tubercles present on top of head, occiput, nape, and limbs, and extending posteriorly beyond base of tail; 43-51 ventral scales; no transversely enlarged, median subcaudal scales; proximal, subdigital lamellae transversely expanded; 17-21 subdigital lamellae on fourth toe; an abrupt transition between posterior and ventral femoral scales; enlarged femoral scales; no femoral or precloacal pores; no precloacal groove; body bearing four wide, bold, dark brown stripes (lateral stripe on each flank and a pair of paravertebral stripes); and a pairwise sequence divergence of 13.0% from its closest relative C. sworderi based on the mitochondrial gene ND2. Cyrtodactylus tebuensis sp. nov. is the first endemic upland species of gekkonid from northeastern Peninsular Malaysia and underscores the necessity for additional field work in all upland systems.


Assuntos
Lagartos/classificação , Filogenia , Animais , Feminino , Lagartos/anatomia & histologia , Malásia , Masculino , Dados de Sequência Molecular , Proteínas de Répteis/genética
20.
Zootaxa ; 3664: 505-24, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26266316

RESUMO

A review of the taxonomic status of the Asian Slug Snake, Asthenodipsas vertebralis (Boulenger, 1900) based on an integrative taxonomic approach using molecular, morphological, color pattern, and ecological data indicate it is composed of three well supported monophyletic lineages: (1) Pulau Tioman and Fraser's Hill, Pahang and Bukit Larut, Perak; Peninsular Malaysia; (2) its sister lineage from Northern Sumatra; and (3) the remaining basal lineage from Peninsular Malaysia. Furthermore, we consider the high sequence divergence (6.3%-10.2%) between these lineages (especially in areas of sympatry) and discrete differences in their morphology, color pattern, and microhabitat preference as evidence they are not conspecific. As such, we resurrect the name A. tropidonotus (Lidth de Jeude, 1923) for the Sumatra populations, restrict the name A. vertebralis to the populations from Pulau Tioman, Genting Highlands, Fraser's Hill, Gunung Benom, and Bukit Larut that contain terrestrial, banded adults; and consider A. lasgalenensis sp. nov. to be restricted to the populations from Fraser's Hill, Cameron Highlands, and Bukit Larut that contain arboreal, unbanded adults.


Assuntos
Colubridae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Colubridae/anatomia & histologia , Colubridae/genética , Colubridae/crescimento & desenvolvimento , Feminino , Malásia , Masculino , Dados de Sequência Molecular , Tamanho do Órgão , Filogenia
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