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1.
PLoS Biol ; 19(6): e3001210, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34061821

RESUMO

Global biodiversity loss is a profound consequence of human activity. Disturbingly, biodiversity loss is greater than realized because of the unknown number of undocumented species. Conservation fundamentally relies on taxonomic recognition of species, but only a fraction of biodiversity is described. Here, we provide a new quantitative approach for prioritizing rigorous taxonomic research for conservation. We implement this approach in a highly diverse vertebrate group-Australian lizards and snakes. Of 870 species assessed, we identified 282 (32.4%) with taxonomic uncertainty, of which 17.6% likely comprise undescribed species of conservation concern. We identify 24 species in need of immediate taxonomic attention to facilitate conservation. Using a broadly applicable return-on-investment framework, we demonstrate the importance of prioritizing the fundamental work of identifying species before they are lost.


Assuntos
Biodiversidade , Classificação , Pesquisa , Animais , Austrália , Lagartos/classificação , Serpentes/classificação
2.
Mol Phylogenet Evol ; 167: 107358, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34774764

RESUMO

Apicomplexa is a large monophyletic phylum of unicellular, parasitic organisms. Reptiles are hosts to both haemosporidian (Haemosporida) and hemogregarine (Eucoccidiorida) apicomplexan blood parasites. Within reptiles our understanding of their diversity remains limited, with a paucity of information from Australia, despite a high diversity of squamates (snakes and lizards). We provide a preliminary assessment of haemosporidian and hemogregarine diversity occurring in lizards across northern tropical Australia, building on existing data with results from a microscopy and genetic assessment. We screened total of 233 blood slides using microscopy and detected hemogregarines in 25 geckos, 2 skinks and 1 agamid, while haemosporidians were detected in 13 geckos. DNA sequencing of 28 samples of the hemogregarine 18S rRNA (∼900 bp) nuclear gene revealed five lineages of Australian lizard hemogregarines within heteroxenous adeleids. We sequenced 10 samples of Haemosporida mtDNA (cytb & coI: ∼1313 bp) and phylogenetic analysis with 30 previously published sequences revealed that the Australian Haemosporida grouped within the Haemoproteidae but were not supported as a monophyletic clade. Our results demonstrate that there is significant undocumented evolutionary diversity in Australian lizard haemosporidian and hemogregarine parasites, with preliminary evidence of significantly higher infection rates in geckos.


Assuntos
Haemosporida , Lagartos , Parasitos , Animais , Austrália , Haemosporida/genética , Lagartos/genética , Filogenia
3.
Biol Lett ; 16(5): 20200040, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32396783

RESUMO

Wallace's Line demarcates the transition between the differentiated regional faunas of Asia and Australia. However, while patterns of biotic differentiation across these two continental landmasses and the intervening island groups (Wallacea) have been extensively studied, patterns of long-term dispersal and diversification across this region are less well understood. Frogmouths (Aves: Podargidae) are a relictual family of large nocturnal birds represented by three extant genera occurring, respectively, in Asia, 'Sahul' (Australia and New Guinea) and the Solomon Islands, thus spanning Wallace's Line. We used new mitochondrial genomes from each of the extant frogmouth genera to estimate the timeline of frogmouth evolution and dispersal across Wallace's Line. Our results suggest that the three genera diverged and dispersed during the mid-Cenozoic between approximately 30 and 40 Mya. These divergences are among the oldest inferred for any trans-Wallacean vertebrate lineage. In addition, our results reveal that the monotypic Solomons frogmouth (Rigidipenna inexpectata) is one of the most phylogenetically divergent endemic bird lineages in the southwest Pacific. We suggest that the contemporary distribution of exceptionally deep divergences among extant frogmouth lineages may be explained by colonization of, and subsequent long-term persistence on, island arcs in the southwest Pacific during the Oligocene. These island arcs may have provided a pathway for biotic dispersal out of both Asia and Australia that preceded the formation of extensive emergent landmasses in Wallacea by at least 10 million years.


Assuntos
Aves , Animais , Ásia , Austrália , Ilhas , Nova Guiné , Filogenia
4.
BMC Evol Biol ; 19(1): 81, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894117

RESUMO

BACKGROUND: Congruent patterns in the distribution of biodiversity between regions or habitats suggest that key factors such as climatic and topographic variation may predictably shape evolutionary processes. In a number of tropical and arid biomes, genetic analyses are revealing deeper and more localised lineage diversity in rocky ranges than surrounding habitats. Two potential drivers of localised endemism in rocky areas are refugial persistence through climatic change, or ecological diversification and specialisation. Here we examine how patterns of lineage and phenotypic diversity differ across two broad habitat types (rocky ranges and open woodlands) in a small radiation of gecko lizards in the genus Gehyra (the australis group) from the Australian Monsoonal Tropics biome. RESULTS: Using a suite of approaches for delineating evolutionarily independent lineages, we find between 26 and 41 putative evolutionary units in the australis group (versus eight species currently recognised). Rocky ranges are home to a greater number of lineages that are also relatively more restricted in distribution, while lineages in open woodland habitats are fewer, more widely distributed, and, in one case, show evidence of range expansion. We infer at least two shifts out of rocky ranges and into surrounding woodlands. Phenotypic divergence between rocky ranges specialist and more generalist taxa is detected, but no convergent evolutionary regimes linked to ecology are inferred. CONCLUSIONS: In climatically unstable biomes such as savannahs, rocky ranges have functioned as zones of persistence, generators of diversity and a source of colonists for surrounding areas. Phenotypic divergence can also be linked to the use of differing habitat types, however, the extent to which ecological specialisation is a primary driver or secondary outcome of localised diversification remains uncertain.


Assuntos
Biodiversidade , Sedimentos Geológicos , Lagartos/fisiologia , Filogenia , Animais , Austrália , Mudança Climática , DNA Mitocondrial/genética , Éxons/genética , Lagartos/genética
5.
Mol Phylogenet Evol ; 140: 106589, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31425788

RESUMO

Australasia harbors very high squamate diversity and is a center of endemicity for a number of major lineages. However, despite this diversity, the diplodactyloid geckos of Australia, New Caledonia, and New Zealand (comprised of three endemic families and >200 species) are the only extant squamates with unequivocal Mesozoic origins in the region. Diplodactyloid geckos also exhibit notable phenotypic and ecological diversity, most strikingly illustrated by the functionally limbless pygopods. Here, we present the first phylogenomic analyses of the pattern and timing of diplodactyloid evolution, based on a dataset of more than 4000 ultraconserved elements (UCEs) from 180 species. These analyses fully resolve nearly all nodes, including a number of intergeneric relationships that have proven problematic in previous studies. The hypothesis that New Caledonia and New Zealand clades represent independent post-KT boundary colonization events of Tasmantis from Australian ancestors is confirmed. Phylogenetic relationships recovered here further highlight contrasting patterns of diversity, most strikingly between insular and/or morphologically highly derived clades that have diversified rapidly, as opposed to other species poor and phylogenetically divergent relictual lineages on mainland Australia. Our new timetree suggests slightly older branching times than previous analyses and does not find a mass extinction event in the early Cenozoic. Finally, our new phylogeny highlights caudal variation across the clade. Most strikingly, the distinctive leaf-tail morphology shown by one family may in fact be plesiomorphic.


Assuntos
Lagartos/classificação , Lagartos/genética , Filogenia , Animais , Australásia , Sequência de Bases , Biodiversidade , Sequência Conservada/genética , Extinção Biológica , Geografia
6.
Proc Biol Sci ; 285(1871)2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29343593

RESUMO

Regions with complex geological histories often have diverse and highly endemic biotas, yet inferring the ecological and historical processes shaping this relationship remains challenging. Here, in the context of the taxon cycle model of insular community assembly, we investigate patterns of lineage diversity and habitat usage in a newly characterized vertebrate radiation centred upon the world's most geologically complex insular region: island arcs spanning from the Philippines to Fiji. On island arcs taxa are ecologically widespread, and provide evidence to support one key prediction of the taxon cycle, specifically that interior habitats (lowland rainforests, montane habitats) are home to a greater number of older or relictual lineages than are peripheral habitats (coastal and open forests). On continental fringes, however, the clade shows a disjunct distribution away from lowland rainforest, occurring in coastal, open or montane habitats. These results are consistent with a role for biotic interactions in shaping disjunct distributions (a central tenant of the taxon cycle), but we find this pattern most strongly on continental fringes not islands. Our results also suggest that peripheral habitats on islands, and especially island arcs, may be important for persistence and diversification, not just dispersal and colonization. Finally, new phylogenetic evidence for subaerial island archipelagos (with an associated biota) east of present-day Wallace's Line since the Oligocene has important implications for understanding long-term biotic interchange and assembly across Asia and Australia.


Assuntos
Evolução Biológica , Ecossistema , Lagartos , Animais , Biota , Melanesia , Filipinas , Filogenia
7.
Mol Phylogenet Evol ; 125: 29-39, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29551525

RESUMO

Regions with complex geological histories present a major challenge for scientists studying the processes that have shaped their biotas. The history of the vast and biologically rich tropical island of New Guinea is particularly complex and poorly resolved. Competing geological models propose New Guinea emerged as a substantial landmass either during the Mid-Miocene or as recently as the Pliocene. Likewise, the estimated timing for the uplift of the high Central Cordillera, spanning the length of the island, differs across models. Here we investigate how early islands and mountain uplift have shaped the diversification and biogeography of Cyrtodactylus geckos. Our data strongly support initial colonisation and divergence within proto-Papuan islands in the Early- to Mid-Miocene, with divergent lineages and endemic diversity concentrated on oceanic island arcs in northern New Guinea and the formerly isolated East-Papuan Composite Terrane. At least four lineages are inferred to have independently colonised hill- and lower-montane forests, indicating that mountain uplift has also played a critical role in accumulating diversity, even in this predominantly lowland lineage. Our findings suggest that substantial land in northern New Guinea and lower-montane habitats date back well into the Miocene and that insular diversification and mountain colonisation have synergistically generated diversity in the geologically complex Papuan region.


Assuntos
Biodiversidade , Evolução Biológica , Lagartos/fisiologia , Animais , Teorema de Bayes , Variação Genética , Geografia , Lagartos/genética , Papua Nova Guiné , Filogenia , Fatores de Tempo
8.
Biol Lett ; 14(6)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29899126

RESUMO

Striking faunal turnover across Asia and Australasia, most famously along the eastern edge of the Sunda Shelf or 'Wallace's Line', has been a focus of biogeographic research for over 150 years. Here, we investigate the origins of a highly threatened endemic lizard fauna (four species) on Christmas Island. Despite occurring less 350 km south of the Sunda Shelf, this fauna mostly comprises species from clades centred on the more distant regions of Wallacea, the Pacific and Australia (more than 1000 km east). The three most divergent lineages show Miocene (approx. 23-5 Ma) divergences from sampled relatives; and have recently become extinct or extinct in the wild, likely owing to the recent introduction of a southeast Asian snake (Lycodon capucinus). Insular distributions, deep phylogenetic divergence and recent decline suggest that rather than dispersal ability or recent origins, environmental and biotic barriers have impeded these lineages from diversifying on the continental Sunda Shelf, and thereby, reinforced faunal differentiation across Wallace's Line. Our new phylogenetically informed perspective further highlights the rapid loss of ancient lineages that has occurred on Christmas Island, and underlines how the evolutionary divergence and vulnerability of many island-associated lineages may continue to be underestimated.


Assuntos
Distribuição Animal , Lagartos/classificação , Filogeografia , Animais , Austrália , Evolução Biológica , Espécies em Perigo de Extinção , Ilhas
9.
Mol Phylogenet Evol ; 115: 62-70, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28739371

RESUMO

Comparisons of biodiversity patterns within lineages that occur across major climate gradients and biomes, can provide insights into the relative roles that lineage history, landscape and climatic variation, and environmental change have played in shaping regional biotas. In Australia, while there has been extensive research into the origins and patterns of diversity in the Australian Arid Zone (AAZ), how diversity is distributed across this biome and the Australian Monsoonal Tropics (AMT) to the north, has been less studied. We compared the timing and patterns of diversification across this broad aridity gradient in a clade of lizards (Strophurus: phasmid geckos) that only occur in association with a unique Australian radiation of sclerophyllous grasses (Triodia: spinifex). Our results indicate that overall genetic diversity is much higher, older and more finely geographically structured within the AMT, including distantly related clades endemic to the sandstone escarpments of the Kimberley and Arnhem Plateau. Niche modelling analyses also suggest that the distribution of taxa in the AMT is more strongly correlated with variation in topographic relief than in the AAZ. The two broad patterns that we recovered - (i) lineage endemism increases as latitude decreases, and (ii) endemism is tightly correlated to rocky regions - parallel and corroborate other recent studies of habitat generalists and specialised saxicoline lineages occurring across these same regions. Early Miocene diversification estimates also suggest that, soon after Triodia grasses colonised Australia and began to diversify in the Miocene, phasmid geckos with Gondwanan ancestry shifted into these grasses, and have subsequently remained closely associated with this unique vegetation type.


Assuntos
Lagartos/classificação , Animais , Austrália , Biodiversidade , Ecossistema , Proteínas do Olho/classificação , Proteínas do Olho/genética , Reguladores de Proteínas de Ligação ao GTP/classificação , Reguladores de Proteínas de Ligação ao GTP/genética , Proteínas de Homeodomínio/classificação , Proteínas de Homeodomínio/genética , Lagartos/genética , NADH Desidrogenase/classificação , NADH Desidrogenase/genética , Fosfoproteínas/classificação , Fosfoproteínas/genética , Filogenia , Receptores da Prolactina/classificação , Receptores da Prolactina/genética
11.
Biol Lett ; 10(10): 20140479, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25296929

RESUMO

The region between the Asian and Australian continental plates (Wallacea) demarcates the transition between two differentiated regional biotas. Despite this striking pattern, some terrestrial lineages have successfully traversed the marine barriers of Wallacea and subsequently diversified in newly colonized regions. The hypothesis that these dispersals between biogeographic realms are correlated with detectable shifts in evolutionary trajectory has however rarely been tested. Here, we analyse the evolution of body size in a widespread and exceptionally diverse group of gekkotan lizards (Cyrtodactylus), and show that a clade that has dispersed eastwards and radiated in the Australopapuan region appears to have significantly expanded its body size 'envelope' and repeatedly evolved gigantism. This pattern suggests that the biotic composition of the proto-Papuan Archipelago provided a permissive environment in which new colonists were released from evolutionary constraints operating to the west of Wallacea.


Assuntos
Tamanho Corporal , Lagartos/classificação , Filogenia , Animais , Austrália , Evolução Biológica , Geografia , Nova Guiné
12.
Zootaxa ; 3753: 483-93, 2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24869510

RESUMO

We describe a new species of very small microhylid frog in the genus Choerophryne from the upper Strickland River area, Western and Southern Highlands Provinces, Papua New Guinea. Choerophryne gracilirostris sp. nov. can be distinguished from congeners by the following combination of characters: small size (SUL 13.5-14.7 mm), moderately long and narrow snout, first finger without expanded disk and advertisement call consisting of 3-5 distinctly pulsed notes repeated in long sequences. Males in the type series were calling from within leaf litter in primary hill rainforest (213-1368 m a.s.l.). The new species is the third Choerophryne known from the southern side of New Guinea's central cordillera. Measurements of a juvenile specimen (rare because most Choerophryne collected are calling males) demonstrate that the distinctive rostral projection of this genus exhibits pronounced positive allometry.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Comunicação Animal , Animais , Anuros/fisiologia , Ecossistema , Dados de Sequência Molecular , Papua Nova Guiné , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA
13.
Zootaxa ; 3768: 139-58, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24871172

RESUMO

Varanus pilbarensis Storr, 1980 is a specialised saxicolous varanid endemic to the Pilbara region of Western Australia. We present genetic and morphological evidence confirming the existence of a divergent southern lineage, here described as V. hamersleyensis sp. nov.. The new species differs noticeably in having a darker colouration and a reduced pattern of small whitish ocelli on the dorsal surface of the limbs only with a largely unbanded tail. By contrast, V. pilbarensis which is redescribed and restricted to the northern lineage, is paler and more boldly patterned with large greyish ocelli on the dorsal and lateral surfaces of the body and a strongly banded tail. The two species have discrete distributions centred on the Chichester and Hamersley Ranges to the north and south of the Fortescue River Basin. This pattern of intraregional genetic structuring is similar to that found in a number of other saxicolous lizard lineages from the Pilbara.


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Animais , DNA Mitocondrial/genética , Demografia , Feminino , Variação Genética , Lagartos/genética , Masculino , Filogenia , Especificidade da Espécie , Austrália Ocidental
14.
Evolution ; 77(1): 138-154, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622227

RESUMO

A key area of interest in evolutionary biology has been understanding the role of ecological opportunity in the formation of adaptive radiations, lineages where speciation and phenotypic diversification are driven by open ecological opportunity. Evolutionary theory posits that adaptive radiations should show initial bursts of ecomorphological diversification and rapid speciation, and that these two processes are correlated. Here, we investigate and contrast these predictions across ecomorphologically diverse continental (Australia) and insular (New Caledonia and New Zealand) radiations of diplodactyloid geckos. We test two key hypotheses: (a) that island colonization and the transition to novel niche-space has resulted in increased rates of speciation and trait diversification and (b) that rates of morphological diversification are correlated across multiple trait axes. Surprisingly, we find that speciation rate is homogenous and morphological diversification rates are idiosyncratic and uncorrelated with speciation rates. Tests of morphological integration suggests that while all traits coevolve, constraint may act differentially on individual axes. This accords with a growing number of studies indicating that ecologically diverse and species-rich radiations can show limited or no evidence of exceptional regime shifts in speciation dynamics or morphological diversification, especially in continental contexts.


Assuntos
Especiação Genética , Lagartos , Animais , Filogenia , Evolução Biológica , Austrália
15.
Zootaxa ; 5263(2): 151-190, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37044991

RESUMO

New Guinea has the most diverse insular frog fauna in the world, and rates of species discovery and description have increased rapidly in the last two decades. Pelodryadid treefrogs are the second most diverse family of anurans on the island but their taxonomy, relationships, and especially ecology remain poorly documented. Based on differences in morphology, advertisement calls (where available) and phylogenetic analyses of a 787 base pair alignment from the mitochondrial ND4 gene and flanking tRNA, we describe five new species of small treefrogs from hill and lower montane forests in the high rainfall belt that straddles the southern versant of Papua New Guinea's Central Cordillera. Three of these species are known only from forest growing on karst substrates, adding to the growing number of herpetofauna species currently known only from the extensive karst habitats of Papua New Guinea's South-fold Mountains. We also describe the arboreal breeding strategies of two of the new species, and report obligate treehole (phytotelm) breeding in New Guinean frogs for the first time. The new phytotelm-breeding species has juveniles with colour and patterning that closely resemble bird droppings, suggesting defensive mimicry or masquerade. A preliminary phylogeny suggests that arboreal-breeding frogs do not form a monophyletic group and that arboreal breeding has evolved multiple times within the New Guinean pelodryadid radiation. A further striking feature of the phylogeny is poor support for most basal nodes in the most diverse radiation of Melanesian Pelodryadidae, suggesting rapid ecological diversification and speciation, potentially following colonisation from Australia and/or mountain uplift. These new taxa and observations highlight previously unrecognised ecological and reproductive diversity in the Melanesian Pelodryadidae.


Assuntos
Anuros , Animais , Papua Nova Guiné , Filogenia
16.
Mol Phylogenet Evol ; 63(2): 255-64, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22209860

RESUMO

The family Diplodactylidae is the most ecologically diverse and geographically widespread radiation of geckos within Australasia. Herein we present a first comprehensive phylogenetic analysis of relationships of diplodactylid geckos currently assigned to the genus Oedura, a group of relatively generalised arboreal Australian geckos. Maximum Likelihood, bayesian and Maximum Parsimony analyses of a combination of over two and a half kilobases of nuclear (PDC, Rag-1) and mitochondrial (ND2, ND4, tRNA) sequence data all identified four distinctive lineages within Oedura s.l. Based on their deep divergences and a suite of diagnostic morphological characters we recognise each of these four lineages as genera, two of which are monotypic and newly described herein. Our molecular data also suggest that Oedura s.l. is not monophyletic, but is instead a plesiomorphic grade restricted to islands of rocky or forested habitat around coastal and central Australia. In contrast, combined analysis of all data suggests the Australian arid zone is dominated by a single comparatively derived and relatively species rich clade including most other genera of Australian Diplodactylidae. Additional data are required to properly resolve basal divergence events within the Diplodactylidae, however the emerging pattern of relationships and divergence is consistent with the hypothesis that monsoonal and temperate lineages are ancestral to the arid zone fauna, but also indicate that arid zone lineages and radiations are relatively old, and potentially date back to the mid Miocene or earlier.


Assuntos
Lagartos/classificação , Lagartos/genética , Filogenia , Animais , Austrália , Sequência de Bases , Teorema de Bayes , Biodiversidade , DNA Mitocondrial/genética , Evolução Molecular , Especiação Genética , Funções Verossimilhança , Modelos Genéticos , RNA/genética , RNA Mitocondrial , Análise de Sequência de DNA
17.
Ginecol Obstet Mex ; 80(6): 389-93, 2012 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-22826966

RESUMO

BACKGROUND: Hysteroscopy is the best approach for the management of Asherman syndrome with reproductive purposes, since it allows a quick diagnosis and treatment of partial or total uterine adhesions. However, there are a few studies on the reproductive outcome in patients with Asherman's syndrome. OBJECTIVE: Evaluate the results of adherenciolisis hysteroscopy in women with Asherman's syndrome. PATIENTS AND METHODS: We performed a cohort study of thirty-nine patients diagnosed with Asherman's syndrome and who underwent surgical hysteroscopic adherenciolisis by bipolar energy through the period from 2006 to June 2011. RESULTS: Thirty-nine cases were reviewed. All patients restored their menstrual cycle in the course of the first three months after surgery. The pregnancy rate after hysteroscopic treatment was 71.7% (28/39), with a son living at home in 28.2% of the cases (11/39). There was no statistical difference to achieve term pregnancy based on a cut-off point at 35 years of age. A history of menstrual pattern before hysteroscopy was associated with perinatal success. All pregnancies were achieved spontaneously within the first year after the procedure. CONCLUSIONS: Spontaneous pregnancy is possible after hysteroscopic adherenciolisis in Asherman's Syndrome. It confirms the viability of using bipolar energy to restore the size and shape of the uterine cavity with minimal endometrial damage and with an exclusive reproductive purpose.


Assuntos
Fertilidade , Ginatresia/cirurgia , Histeroscopia , Gravidez/estatística & dados numéricos , Adulto , Estudos de Coortes , Feminino , Humanos , Estudos Retrospectivos
18.
Commun Biol ; 5(1): 1182, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333588

RESUMO

Identifying hotspots of biological diversity is a key step in conservation prioritisation. Melanesia-centred on the vast island of New Guinea-is increasingly recognised for its exceptionally species-rich and endemic biota. Here we show that Melanesia has the world's most diverse insular amphibian fauna, with over 7% of recognised global frog species in less than 0.7% of the world's land area, and over 97% of species endemic. We further estimate that nearly 200 additional candidate species have been discovered but remain unnamed, pointing to a total fauna in excess of 700 species. Nearly 60% of the Melanesian frog fauna is in a lineage of direct-developing microhylids characterised by smaller distributions than co-occurring frog families, suggesting lineage-specific high beta diversity is a key driver of Melanesian anuran megadiversity. A comprehensive conservation status assessment further highlights geographic concentrations of recently described range-restricted threatened taxa that warrant urgent conservation actions. Nonetheless, by world standards, the Melanesian frog fauna is relatively intact, with 6% of assessed species listed as threatened and no documented extinctions; and thus it provides an unparalleled opportunity to understand and conserve a megadiverse and relatively intact insular biota.


Assuntos
Biodiversidade , Biota , Animais , Melanesia , Anuros
19.
Biodivers Conserv ; 31(8-9): 2045-2062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35633848

RESUMO

Cryptic ecologies, the Wallacean Shortfall of undocumented species' geographical ranges and the Linnaean Shortfall of undescribed diversity, are all major barriers to conservation assessment. When these factors overlap with drivers of extinction risk, such as insular distributions, the number of threatened species in a region or clade may be underestimated, a situation we term 'cryptic extinction risk'. The genus Lepidodactylus is a diverse radiation of insular and arboreal geckos that occurs across the western Pacific. Previous work on Lepidodactylus showed evidence of evolutionary displacement around continental fringes, suggesting an inherent vulnerability to extinction from factors such as competition and predation. We sought to (1) comprehensively review status and threats, (2) estimate the number of undescribed species, and (3) estimate extinction risk in data deficient and candidate species, in Lepidodactylus. From our updated IUCN Red List assessment, 60% of the 58 recognized species are threatened (n = 15) or Data Deficient (n = 21), which is higher than reported for most other lizard groups. Species from the smaller and isolated Pacific islands are of greatest conservation concern, with most either threatened or Data Deficient, and all particularly vulnerable to invasive species. We estimated 32 undescribed candidate species and linear modelling predicted that an additional 18 species, among these and the data deficient species, are threatened with extinction. Focusing efforts to resolve the taxonomy and conservation status of key taxa, especially on small islands in the Pacific, is a high priority for conserving this remarkably diverse, yet poorly understood, lizard fauna. Our data highlight how cryptic ecologies and cryptic diversity combine and lead to significant underestimation of extinction risk. Supplementary Information: The online version contains supplementary material available at 10.1007/s10531-022-02412-x.

20.
Mol Phylogenet Evol ; 59(3): 664-74, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21421065

RESUMO

Clades that predate the origin of biomes that they inhabit provide unique opportunities to examine both when major environmental transitions occurred, and how lineages adapted to these changes. The isolated island continent Australia has undergone a profound environmental transition through the Miocene, from relatively mesic to predominantly arid; however, we have much to learn about both the timing of this change, and how organisms may have responded to it. The family Carphodactylidae is an ancient Gondwanan group of geckos that occurs across all major Australian biomes. A multilocus (ND2, Rag-1, c-mos) phylogenetic and dating analysis of the most ecologically diverse clade within this group, the genus Nephrurus (sensuBauer, 1990) reveals that two of three morphological taxa historically recognized (the 'spiny knob-tails' and 'Underwoodisaurus') are relatively species depauperate, pleisomorphic basal grades that diversified through the late Oligocene and early Miocene, and are now absent from most of the arid biome. Based on their deep divergence and morphological distinctiveness we recognize two lineages (milii and sphyrurus) as monotypic genera, the later of which is named herein (Uvidicolus nov. gen). In contrast, a third morphological group, the 'smooth knob-tails,' is a monophyletic group of five exclusively arid zone burrowing species that has radiated relatively recently (mid-Miocene). Our phylogeny indicates that successful colonization of this novel and challenging biome by Nephrurus correlates with an initial shift to terrestriality and adaptation to at least seasonally arid conditions around the early Miocene, and the eventual evolution and subsequent mid-Miocene radiation of a lineage specialized for burrowing.


Assuntos
Lagartos/classificação , Lagartos/genética , Filogenia , Animais , Variação Genética/genética , Funções Verossimilhança
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