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Dry rainforests and open woodlands occur across much of eastern Australia. However, the biogeographic history of these habitats remains poorly known, especially when compared to nearby moist rainforest areas. Land snails are commonly used as model organisms to understand patterns of origins of regional endemism due to their low vagility. Here we present an analysis of patterns of mitochondrial genetic diversity in three camaenid snail lineages with distributions centred on vine-thicket and open woodland habitats of eastern Queensland, specifically Euryladra from open woodlands, Brigaladra from inland semievergreen vine thickets, and Figuladra from coastal vine thickets. Lineages from habitats west of the Great Dividing Range show relatively low genetic divergence between localities, with particularly low structuring in the open woodland taxon Euryladra. Figuladra from vine-thicket habitats closer to the coast shows relatively deeper genetic divergence, with marked divergences between some upland and lowland areas in south-east Queensland, and across the St Lawrence Gap. This structuring suggests that taxa associated with vine thicket habitats have had a more discernible history of isolation than open woodlands. This said, genetic divergence across many vine thickets patches in lowland coastal regions is also shallow, suggesting many apparently disjunct vine thicket habitats and their associated species also have a recent history of connectivity. Dry rainforests and open woodlands occur across much of eastern Australia. Land snails are model organisms to understand regional biodiversity due to their low vagility. We present an analysis of genetic diversity in three eastern Queensland camaenid snail lineages. These analyses reveal that there is a difference in the genetic diversity of species living in open woodland compared to those inhabiting dry rainforest. Photograph by Lorelle Stanisic. [ABSTRACT FROM AUTHOR]

Upstream colonizations from islands to continents have played an important role in two major global bird radiations: the oscine passerines and the pigeons. Here, we investigate insular diversification and upstream dispersal dynamics of pigeons (Columbiformes) within the Indo-Australian Archipelago using a supermatrix fossil-calibrated phylogeny and model-based biogeographical analyses. These analyses show that the islands of Melanesia, now centred on New Guinea and considered separately from Australia, have been a centre of pigeon diversification since the Eocene–Oligocene transition (~34 Mya). Geological reconstructions are concordant in suggesting that arc terranes and continental ribbon fragments that underpin the contemporary Melanesian region might have formed extensive archipelagos for much of the Oligocene and Miocene. These islands are also inferred to have functioned as a net source of pigeon lineages for Asia and especially Australia. Arboreal fruit-eating pigeons have colonized nearby continents on multiple occasions yet show little evidence of subsequent radiation. Insular terrestrial pigeons have been largely unable to colonize Asia, and a single Miocene colonization of Australia preceded an endemic radiation. Upstream dispersal may well be a frequent process in the history of the Indo-Australian Archipelago and surrounds, however ecological and environmental factors likely place strong constraints on its success and evolutionary outcomes. [ABSTRACT FROM AUTHOR]

Species endemic to high elevations are predicted to see declines in their suitable habitat under future global climate change, even in protected or little disturbed areas. However, such risks are often not included in conservation assessments, especially when appropriate models to predict climate change impacts are not available. Here, we use species distribution models to explore the likely impacts of climate change and recent megafires on the status of two high‐elevation cloud forest‐centred lizards from Australia that were listed as Least Concern in a recent (2017) IUCN Red List assessment of Australian reptiles. We found both species (Harrisoniascincus zia and Silvascincus tryoni) are predicted to lose all suitable habitat by 2050, under 'optimistic' future climate projections. We also found that 52.34–48.5% of H. zia modelled suitable habitat was potentially affected by recent and unprecedented megafires in eastern Australia, while only 0.02–0% of S. tryoni habitat was affected. Our results support upgrading the IUCN Red Listings of H. zia and S. tryoni to vulnerable and endangered, respectively. Our data also highlight an alarming paucity in the number of verified records for these species over the last decade, at precisely the time when these records are becoming critical to testing and validating predictions of declines. The next decade looms as a critical period to establish baseline data sets on the distribution and genetic diversity of these high‐elevation taxa. For reasonably visible and easily identifiable species such as these skinks, citizen science approaches may offer a key path to addressing this challenge. [ABSTRACT FROM AUTHOR]

Across Australia's monsoon tropics and vast arid zone isolated regions or 'islands' of upland or rocky habitat are home to disjunct populations of many taxa of plants and animals. Comparative analyses of lineages that occur across these habitat islands provide opportunities to understand when and how environmental change drove isolation and diversification across arid Australia. Here we present an analysis of mitochondrial genetic diversity across disjunct populations of geckos in the Nephrurus asper group. Dating analyses suggest that disjunct and genetically divergent populations spanning the northern half of Australia diverged through the Plio–Pleistocene. Based on the timing of divergence and current habitat associations we hypothesise that species in this lineage were isolated by the expansion of unsuitable arid-zone habitats from the late Pliocene onwards. Across most areas, these barriers appear to be sandy or stony deserts. However, in eastern Australia genetically divergent populations are separated by grassland on flat vertisol-dominated soils ('blacksoils'), suggesting that these habitats also expanded during the late Pliocene aridification. Finally, we show that western Queensland populations formerly referred to N. asper are genetically divergent and diagnosable on the basis of colour pattern and, herein, recognise these populations as a distinct species. https://zoobank.org/urn:lsid:zoobank.org:pub:9508CAAA-D014-452D-A3DA-325851615FA7 An assessment of mitochondrial diversity in geckos of the Nephrurus asper group reveals Plio–Pleistocene vicariance of isolated populations spanning the deserts and savannahs of northern Australia. The spread and expansion of sandy deserts, stony deserts and blacksoil grasslands is hypothesised to be the process that isolated these populations. A genetically divergent lineage from rocky habitats in arid western Queensland is described as a new species. Photograph by Angus Emmott. [ABSTRACT FROM AUTHOR]

Mountain regions are centers of biodiversity endemism at a global scale but the role of arid‐zone mountain ranges in shaping biodiversity patterns is poorly understood. Focusing on three guilds of taxa from a desert upland refugium in Australia, we sought to determine: (a) the relative extent to which climate, terrain or geological substrate predict endemism, and (b) whether patterns of endemism are complimentary across broad taxonomic guilds. We mapped regional endemism for plants, land snails, and vertebrates using combined Species Distribution Models (SDMs) for all endemic taxa (n = 82). We then modelled predictors of endemism using Generalised Additive Models (GAMs) and geology, terrain, and climate variables. We tested for the presence of inter‐ and intraguild hotspots of endemism. Many individual plant and land snail taxa were tightly linked with geology, corresponding to small distributions. Conversely, most vertebrate taxa were not constrained to specific geological substrates and occurred over larger areas. However, across all three guilds climate was the strongest predictor of regional endemism, particularly for plants wherein discrete hotspots of endemism were buffered from extreme summer temperatures. Land snail and vertebrate endemism peaked in areas with highest precipitation in the driest times of the year. Hotspots of endemism within each guild poorly predicted endemism in other guilds. We found an overarching signal that climatic gradients play a dominant role in the persistence of endemic taxa in an arid‐zone mountain range system. An association with higher rainfall and cooler temperatures indicates that continuing trends toward hotter and drier climates may lead to range contractions in this, and potentially other, arid‐zone mountain biotas. Contrasting patterns of endemism across guilds highlight the need to couple comprehensive regional planning for the protection of climate refugia, with targeted management of more localized and habitat specialist taxa. [ABSTRACT FROM AUTHOR]

Australia and New Guinea (together referred to as Sahul) were linked by land for much of the late Tertiary and share many biotic elements. However, New Guinea is dominated by rainforest, and northern Australia by savannah. Resolving patterns of biotic interchange between these two regions is critical to understanding the expansion and contraction of both habitat types. The green tree frog (Litoria caerulea) has a vast range across northern and eastern Australia and New Guinea. An assessment of mitochondrial and morphological diversity in this nominal taxon in New Guinea reveals two taxa. True Litoria caerulea occurs in disjunct savannahs of the Trans-Fly, Central Province and across northern Australia, with very low genetic divergence, implying late Pleistocene connectivity. A previously unrecognised taxon is endemic to New Guinea and widespread in lowland swampy rainforest. Date estimates for the divergence of the new species suggest Pliocene connectivity across lowland tropical habitats of northern Australia and New Guinea. In contrast, the new species shows shallow phylogeographic structuring across the central mountains of New Guinea, implying recent dispersal between the northern and southern lowlands. These results emphasise that the extent and connectivity of lowland rainforest and savannah environments across northern Australia and southern New Guinea have undergone profound shifts since the late Pliocene. http://zoobank.org/urn:lsid:zoobank.org:pub:A577A415-0B71-4663-B4C1-7271B97298CD An assessment of mitochondrial and morphological diversity in frogs previously assigned to Litoria caerulea from New Guinea reveals two taxa. Shallow genetic divergence in true L. caerulea from across southern New Guinea and Australia implies recent Pleistocene connectivity across now isolated savannahs, while the more deeply divergent new species suggests earlier Pliocene divergence across lowland tropical habitats of Sahul. Photo by S. J. Richards. [ABSTRACT FROM AUTHOR]

For over two decades, assessments of geographic variation in mtDNA and small numbers of nuclear loci have revealed morphologically similar, but genetically divergent, intraspecific lineages in lizards from around the world. Subsequent morphological analyses often find subtle corresponding diagnostic characters to support the distinctiveness of lineages, but occasionally do not. In recent years it has become increasingly possible to survey geographic variation by sequencing thousands of loci, enabling more rigorous assessment of species boundaries across morphologically similar lineages. Here we take this approach, adding new, geographically extensive SNP data to existing mtDNA and exon capture datasets for the Gehyra australis and G. koira species complexes of gecko from northern Australia. The combination of exon-based phylogenetics with dense spatial sampling of mitochondrial DNA sequencing, SNP-based tests for introgression at lineage boundaries and newly-collected morphological evidence supports the recognition of nine species, six of which are newly described here. Detection of discrete genetic clusters using new SNP data was especially convincing where candidate taxa were continuously sampled across their distributions up to and across geographic boundaries with analyses revealing no admixture. Some species defined herein appear to be truly cryptic, showing little, if any, diagnostic morphological variation. As these SNP-based approaches are progressively applied, and with all due conservatism, we can expect to see a substantial improvement in our ability to delineate and name cryptic species, especially in taxa for which previous approaches have struggled to resolve taxonomic boundaries. [ABSTRACT FROM AUTHOR]

New Guinea has been considered both as a refuge for mesic rainforest-associated lineages that contracted in response to the late Cenozoic aridification of Australia and as a centre of biotic diversification and radiation since the mid-Miocene or earlier. Here, we estimate the diversity and a phylogeny for the Australo-Papuan forest dragons (Sauria: Agamidae; ~20 species) in order to examine the following: (1) whether New Guinea and/or proto-Papuan Islands may have been a biogeographical refuge or a source for diversity in Australia; (2) whether mesic rainforest environments are ancestral to the entire radiation, as may be predicted by the New Guinea refuge hypothesis; and (3) more broadly, how agamid ecological diversity varies across the contrasting environments of Australia and New Guinea. Patterns of lineage distribution and diversity suggest that extinction in Australia, and colonization and radiation on proto-Papuan islands, have both shaped the extant diversity and distribution of forest dragons since the mid-Miocene. The ancestral biome for all Australo-Papuan agamids is ambiguous. Both rainforest and arid-adapted radiations probably started in the early Miocene. However, despite deep-lineage diversity in New Guinea rainforest habitats, overall species and ecological diversity is low when compared with more arid areas, with terrestrial taxa being strikingly absent. [ABSTRACT FROM AUTHOR]

Aim Savanna biomes cover around 20% of land surfaces, yet the origins and processes that have shaped their biodiversity remain understudied. Here, we assess the timing of diversification and how patterns of genetic diversity vary along an aridity gradient in specialized saxicoline gecko clades ( Oedura spp.) from the tropical savannas of northern Australia. Location Australian Monsoonal Tropics ( AMT), Kimberley region (Western Australia). Methods We compiled mitochondrial and nuclear data for two Kimberley endemic lizard clades ( Oedura filicipoda/murrumanu and O. gracilis), and allied non-Kimberley taxa ( O. marmorata complex). Species delimitation methods were used to identify evolutionary lineages, Maximum-likelihood and Bayesian phylogenetic methods were employed to assess relationships and diversification timeframes, and rainfall data and range sizes were tested for correlations. Results Phylogenetic analyses of cryptic or recently discovered lineage diversity revealed late-Miocene to early-Pliocene crown ages. Microendemism and diversity were highest in high-rainfall regions, while the most widespread lineages occurred in the central and south-east Kimberley, and showed evidence of introgression with parapatric lineages. Main conclusions The initial diversification in both clades was broadly concordant with global climatic events linked to the expansion of savanna biomes in the lateMiocene. Higher endemism in mesic and refugial areas suggests long histories of localized persistence, while wider distributions and evidence of introgression suggest a dynamic history at the arid-monsoonal interface. [ABSTRACT FROM AUTHOR]

Aim Lineages in many parts of the world have distributions that have been shaped by range contraction in the face of deteriorating climatic conditions through the Neogene. When such lineages now consist of widely spaced vicariant populations (vicars) they provide opportunities (1) to compare and contrast the timing and pattern of diversification within and between major geographical regions, and (2) to examine how differential interactions with geography, climate and localized adaptation may have shaped idiosyncratic patterns of genetic diversification. Location Australian Arid Zone ( AAZ) and Australian Monsoonal Tropics ( AMT). Methods We compiled and analysed mitochondrial DNA, nuclear DNA and allozyme datasets to determine the evolutionary history and genetic diversity of isolated populations of a gecko lineage (the Oedura marmorata complex and related taxa) distributed across the Australian monsoonal and arid biomes. Results Three widely allopatric lineages in the AAZ diverged during the late Miocene and Plio-Pleistocene. Populations in the AMT display much greater genetic turnover than those in the AAZ over equivalent geographical distances, and also include several lineages that are of equal or greater age than all diversity in the AAZ. Saxicoline lineages tend to show higher genetic diversity and/or have more restricted ranges than arboreal relatives in both biomes. Main conclusions Lineages of Oedura show contrasting patterns of diversification in the two major biomes they inhabit. Diversity in the arid biome is younger and restricted to widely separated refugia, reflecting the younger age and pervasive harshness of this environment. Higher diversity in the AMT is also indicative of persistence, but at much finer geographical scales and broadly over a longer period of time, perhaps reflecting the more continuous spatial and temporal distribution of equitable habitats within this region. Finally, the wider distribution of arboreal lineages in both biomes suggests that ecological flexibility has also shaped the contrasting patterns of distribution in related lineages, and supports the contention that an association with rocks has shaped high lineage diversity in many taxa from the Australian Monsoonal Tropics. [ABSTRACT FROM AUTHOR]

A new species of giant trapdoor spider, Euoplos dignitas sp. nov. (family Idiopidae), is described from the Brigalow Belt of inland Queensland, Australia. Phylogenetic analysis of a six gene molecular dataset for the tribe Euoplini reveals that this species is sister to the spinnipes-group from eastern Queensland, and unrelated to a morphologically similar congener (E. grandis Wilson & Rix, 2019) that occurs further south in the Brigalow Belt. Both E. dignitas sp. nov. and E. grandis are very large, scopulate, plug door-building trapdoor spiders from transitional woodland habitats on vertosols ('black soils'), with superficially similar females and strongly sexually-dimorphic 'honey-red' males. Information on the known biology and distribution of E. dignitas sp. nov. is summarized, and a conservation assessment is provided under the International Union for Conservation of Nature's (IUCN) Red List Criteria, indicating that this species is likely Endangered. [ABSTRACT FROM AUTHOR]

The south-eastern Australian tree frogs Litoria ewingii and L. verreauxii are related species that share a broad zone of sympatry. Despite evidence of reproductive character displacement and positive assortative mating in sympatry, a small number of studies have provided inconclusive evidence that occasional hybridisation may occur. We assessed morphological and acoustic divergence between males from two localities where L. ewingii and L. verreauxii occur in sympatry. Several acoustic and morphological traits were found to be divergent between individuals assigned a priori to parental species based on a single acoustic character of the male advertisement call that was previously identified to be diagnostic (pulse number). In contrast, multivariate analysis indicated that at least five adult males identified a priori as putative hybrids (on the basis of intermediate pulse number) were also intermediate in morphology and other aspects of acoustic structure. The concordance of intermediate morphological and acoustic phenotypes supports the hypothesis that despite strong premating isolation, mismating results in at least a small number of hybrid adult males where these species occur in sympatry. This new evidence of hybridisation between L. ewingii and L. verreauxii underlines that there remains much to learn about this model system for understanding hybrid zone dynamics. We investigated evidence of hybridisation between the south-eastern Australian tree frogs Litoria ewingii and L. verreauxii at two localities where the species occur in sympatry. Morphological and acoustic analyses showed that several traits were divergent between parental species and that five individuals were intermediate, strongly suggestive of hybridisation. [ABSTRACT FROM AUTHOR]

Abstract: 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 (sensu) 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. [Copyright &y& Elsevier]

Background: Molecular studies have revealed that many putative 'species' are actually complexes of multiple morphologically conservative, but genetically divergent 'cryptic species'. In extreme cases processes such as nonadaptive diversification (speciation without divergent selection) could mask the existence of ancient lineages as divergent as ecologically and morphologically diverse radiations recognised as genera or even families in related groups. The identification of such ancient, but cryptic, lineages has important ramifications for conservation, biogeography and evolutionary biology. Herein, we use an integrated multilocus genetic dataset (allozymes, mtDNA and nuclear DNA) to test whether disjunct populations of the widespread nominal Australian gecko species Crenadactylus ocellatus include distinct evolutionary lineages (species), and to examine the timing of diversification among these populations. Results: We identify at least 10 deeply divergent lineages within the single recognised species Crenadactylus ocellatus, including a radiation of five endemic to the Kimberley region of north-west Australia, and at least four known from areas of less than 100 km2. Lineages restricted to geographically isolated ranges and semi-arid areas across central and western Australia are estimated to have began to diversify in the late Oligocene/early Miocence (∼20-30 mya), concurrent with, or even pre-dating, radiations of many iconic, broadly sympatric and much more species-rich Australian vertebrate families (e.g. venomous snakes, dragon lizards and kangaroos). Conclusions: Instead of a single species, Crenadactylus is a surprisingly speciose and ancient vertebrate radiation. Based on their deep divergence and no evidence of recent gene flow, we recognise each of the 10 main lineages as candidate species. Molecular dating indicates that the genus includes some of the oldest vertebrate lineages confounded within a single species yet identified by molecular assessments of diversity. Highly divergent allopatric lineages are restricted to putative refugia across arid and semi-arid Australia, and provide important evidence towards understanding the history and spread of the Australian arid zone, suggesting at a minimum that semi-arid conditions were present by the early Miocene, and that severe aridity was widespread by the mid to late Miocene. In addition to documenting a remarkable instance of underestimation of vertebrate species diversity in a developed country, these results suggest that increasing integration of molecular dating techniques into cryptic species delimitation will reveal further instances where taxonomic conservatism has led to profound underestimation of not only species numbers, but also highly significant phylogenetic diversity and evolutionary history. [ABSTRACT FROM AUTHOR]

Aim Gondwanan lineages are a prominent component of the Australian terrestrial biota. However, most squamate (lizard and snake) lineages in Australia appear to be derived from relatively recent dispersal from Asia (< 30 Ma) and in situ diversification, subsequent to the isolation of Australia from other Gondwanan landmasses. We test the hypothesis that the Australian radiation of diplodactyloid geckos (families Carphodactylidae, Diplodactylidae and Pygopodidae), in contrast to other endemic squamate groups, has a Gondwanan origin and comprises multiple lineages that originated before the separation of Australia from Antarctica. Location Australasia. Methods Bayesian (beast) and penalized likelihood rate smoothing (PLRS) (r8s) molecular dating methods and two long nuclear DNA sequences ( RAG-1 and c- mos) were used to estimate a timeframe for divergence events among 18 genera and 30 species of Australian diplodactyloids. Results At least five lineages of Australian diplodactyloid geckos are estimated to have originated > 34 Ma (pre-Oligocene) and basal splits among the Australian diplodactyloids occurred c. 70 Ma. However, most extant generic and intergeneric diversity within diplodactyloid lineages appears to post-date the late Oligocene (< 30 Ma). Main conclusions Basal divergences within the diplodactyloids significantly pre-date the final break-up of East Gondwana, indicating that the group is one of the most ancient extant endemic vertebrate radiations east of Wallace’s Line. At least five Australian lineages of diplodactyloid gecko are each as old or older than other well-dated Australian squamate radiations (e.g. elapid snakes and agamids). The limbless Pygopodidae (morphologically the most aberrant living geckos) appears to have radiated before Australia was occupied by potential ecological analogues. However, in spite of the great age of the diplodactyloid radiation, most extant diversity appears to be of relatively recent origin, a pattern that is shared with other Australian squamate lineages. [ABSTRACT FROM AUTHOR]

Abstract: We examine species boundaries and phylogenetic relationships within the Australian diplodactyline geckos currently assigned to Diplodactylus granariensis and Diplodactylus vittatus using data from multiple allozyme loci, the mitochondrial ND2 gene and published karyotypic studies. These analyses uncover at least six morphologically cryptic but genetically distinctive species. The taxa identified correspond poorly with the existing taxonomy and represent a paraphyletic assemblage with respect to a number of other Diplodactylus species included in analyses. Molecular dating indicates that the species identified evolved considerably before the Pleistocene, and that the basal node of the D. vittatus species group (as redefined here) is of comparable age to entire radiations of other Australian squamate families. The antiquity of this one small group within the diplodactyline geckos suggests that further study of patterns of diversification in the diplodactylines will provide both a valuable insight into long-term patterns of environmental change in the Australian continent and a useful contrast for analysis of patterns of radiation in other Australian lizard groups. [Copyright &y& Elsevier]

The article discusses racism in Australian sports and how it remains an issue despite efforts to combat it through member protection policies, anti-discrimination strategies, and laws against racial and religious vilification.

[Display omitted] • Significant undocumented evolutionary diversity in Australian lizard blood parasites. • Haemosporidian and hemogregarine parasites in Australian lizards are not monophyletic. • Hemogregarine parasetemia infections was generally low (<1%) with highest 14.5%. • Haemosporidian parasitemia was higher, with four above 10% and one of 81%. • Significantly higher infection rates in geckos compared to other lizard families. 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. [ABSTRACT FROM AUTHOR]

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., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE). All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

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., Competing Interests: The authors have declared that no competing interests exist.

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.

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.

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., (© 2018 The Authors.)

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., (© 2014 The Author(s) Published by the Royal Society. All rights reserved.)

A major problem for biodiversity conservation and management is that a significant portion of species diversity remains undocumented (the 'taxonomic impediment'). This problem is widely acknowledged to be dire among invertebrates and in developing countries; here, we demonstrate that it can be acute even in conspicuous animals (reptiles) and in developed nations (Australia). A survey of mtDNA, allozyme and chromosomal variation in the Australian gecko, genus Diplodactylus, increases overall species diversity estimates from 13 to 29. Four nominal species each actually represent multi-species complexes; three of these species complexes are not even monophyletic. The high proportion of cryptic species discovered emphasizes the importance of continuing detailed assessments of species diversity, even in apparently well-known taxa from industrialized countries.