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The Gesneriaceae consists of around 150 genera and c. 3750 species with a predominantly tropical and subtropical distribution across all continents. Although previous studies have proposed an American origin of Gesneriaceae, the biogeographic history of this pantropical plant family is still unclear, particularly in the Old World. To address this, we assembled the most comprehensively sampled matrix of Gesneriaceae with 143 Gesneriaceae genera and 355 species, including key samples from Sri Lanka analysed here for the first time. We generated molecular phylogenies based on four plastid gene regions (ndhF, matK, rps16 and trnL-F), obtained fossil-calibrated trees, and reconstructed ancestral areas and dispersal routes using Bayesian methods. Our results confirm the origin for the family in the Early Palaeocene (67. Ma) in the region of present day Central America & Andean South America, and that diversity in the Old World originated from a longdistance dispersal event from South America around 59 Ma, most likely to the Indian plate, which was an island at the time. This lineage then dispersed to Malesia and later East Asia, which would ultimately become a major centre of diversity and source of many dispersals to other regions. Our results thus highlight the Indian plate as a likely key player in the early diversification of Old World Gesneriaceae, even though it is now more diverse elsewhere, and hence offer novel insights into this plant family’s dispersal routes and areas of diversification in the Old World.

Plant species diversity may be considerably underestimated, especially in evolutionarily complex genera and in diversity hotspots that have enabled long‐term species persistence and diversification, such as the Balkan Peninsula. Here, we address the topic of underexplored plant diversity and underlying evolutionary and biogeographic processes by investigating the hygrophytic mountain species complex of Cardamine acris s.l. distributed in the Balkans (three subspecies within C. acris) and northwestern Anatolia (C. anatolica). We performed a series of phylogenetic and phylogeographic analyses based on restriction‐site associated DNA sequencing (RADseq) and target enrichment (Hyb‐Seq) data in combination with habitat suitability modelling. We found C. anatolica as a clade nested within the Balkan C. acris, probably resulting from a founder event, and uncovered three allopatric cryptic lineages within C. acris subsp. acris, allowing us to recognise a total of six entities in this complex. We observed the deepest genetic split within C. acris subsp. acris in the western Balkans, which was at odds with taxonomy and showed no distribution gap. We inferred vicariance as the most likely process for population divergence in the Balkans, accompanied by gene flow between the recognised entities, which was consistent with the modelled habitat suitability dynamics. Furthermore, we discovered several polyploid populations in C. acris, representing both pure intra‐ and inter‐lineage hybrid polyploids, but detected only minor traces of hybridization with related congeners. Overall, our results illustrate that diverse evolutionary processes may influence the history of mountain plant species in the Balkan Peninsula, including vicariance, reticulation, polyploidization and cryptic diversification. [ABSTRACT FROM AUTHOR]

Aim: To date a vicariant event through the mutualistic relationship of a hylid frog and its bromeliad host found across two isolated mountain ranges as part of an island–continental split and to use this information to calibrate a molecular dating analysis of hylids. Location: South America. Time Period: Pliocene. Major Taxa Studied: Treefrogs, Arboranae. Methods: Pliocene tectonic movements sank a portion of a mountain range that connected present‐day Trinidad (island) and northern Venezuela, eventually isolating populations of the golden tree frog Phytotriades auratus and its host bromeliad Glomeropitcairnia erectiflora on both sides of a saltwater barrier. We estimated the submersion rate timing of the vicariant event, then employed ecological niche modelling to establish the distribution of the frog and its host to the Pliocene. We generated nucleotide sequence data for the hylid on each side of the marine barrier and proposed a biogeographic calibration for the split between populations. Using Bayesian phylogenetic analysis, we evaluated the impact of incorporating this biogeographic calibration on estimates of treefrog divergence times. Results: A relatively continuous, high‐elevation mountain range existed before the Pliocene and the opening of the Gulf of Paria (4.45 ± 0.85 Ma). Phytotriades auratus and G. erectiflora would have been distributed across the Paria and Northern Range mountains as a single population since the Pliocene. Divergence times among treefrogs (Arboranae) were older than those inferred using fossil calibrations alone, with mean age estimates for subfamilies and genera being ~2 and ~1.2 million years older, respectively. Main Conclusions: Our study presents a biogeographic calibration based on a vicariant model that connects the evolution of the populations of a hylid through geology and ecological data. The implementation of this date as a molecular clock calibration reduces the uncertainty in date estimates for the shallower nodes in the phylogeny of Arboranae. [ABSTRACT FROM AUTHOR]

The North Pacific distribution of coastal aleocharines has been explained as the result of either dispersal or vicariance. The rove beetle genus Psammostiba is a marine littoral group that occurs on the Pacific coasts of the Northern Hemisphere. We performed phylogenetic analysis of Psammostiba using molecular characters (4685 bp) to investigate their biogeographic patterns. The data were analysed using parsimony, Bayesian and maximum likelihood methods. Model‐based analyses showed the same pattern of Psammostiba species relationships, but parsimony analysis yielded different species relationships for the unresolved clade of Psammostiba. According to the reconstruction of the ancestral areas, both vicariance (two events) and dispersal (one event) have played roles in shaping its current distribution. Biogeographical analyses suggest that the common ancestor of Psammostiba occurred widely along the Pacific coasts of the Northern Hemisphere and underwent vicariance events. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions The aim of this study is to infer the geographic dispersal paths and the environmental conditions that shaped the historical biogeography of Brachistosternus scorpions in South America. We evaluated the role that altitude and aridity had on the geographic distance that each species dispersed from the location of the genus common ancestor. Based on the previous studies, we evaluated the hypothesis postulating that species geographic expansion was promoted by arid conditions in high altitudes.South America.Brachistosternus genus.We integrated two methodological approaches in this study, the phylogenetic Geographical model and the Conductance model, considering the uncertainty associated with the phylogenetic relationship and the species classification. The Geo model infers the locations of ancestral species in a phylogenetic tree, assuming a spherical space and using samples of georeferenced locations for every species as input data. It allows us to estimate the species dispersal routes and distances from the location of the genus common ancestor. The Conductance model is based on the circuit theory and infers the geographic route and distance of least resistance between an origin and destination point. We defined the origin as the location of the genus common ancestor obtained from the Geo model and a destination point as the current geographic location of each species. This model infers the geographic routes with the least cost of resistance for dispersal in a landscape of varying altitude and aridity. Finally, we evaluated the correlation between the two dispersal distances each species have moved from the location of the common ancestor, that is, the distance inferred from the Geo model and from the Conductance model.The Geo model shows that Brachistosternus's geographical origin was most likely along the coast of south Peru, and central Chile. From this location, extant species dispersed thorough routes ranging from 873 to 2800 km in average. The Conductance model that considers the routes with least resistance to elevation and aridity simulated dispersal distances that are highly correlated with the species dispersal distances obtained from the Geo model.We revealed the geographic dispersal routes, with the least resistance to the pressures imposed by changes in altitude and aridity, that 55 species of scorpions have probably followed in the last 30 million years in South America. These geographic routes that went along the Andean Mountains and the arid zones of South America shaped the current spatial distribution of the genus Brachistosternus. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Methods Results Main Conclusions Amphiamerican New World fishes provide a unique opportunity to explore the impact of geological processes and the formation of geographic barriers on biological diversification across both spatial and temporal dimensions. We employed phylogenetic and biogeographic methods to assess the impact of the emergence of the Isthmus of Panama on the evolutionary history of snooks.Eastern tropical Pacific and western Atlantic Oceans.Bayesian methods were used for phylogenetic inference and divergence time estimation, incorporating the fossil record of Carangidae, Centropomidae, Istiophoriformes, Latidae and Sphyraenidae to establish a timeline using the methods of stratigraphic intervals for node calibration density specification. Biogeographic models were fitted to test the hypothesis that transisthmian vicariant events are coeval with the Isthmus closure. To estimate ancestral range probability and perform stochastic mapping, we utilised BioGeoBears and the parameters from the best‐fitting model. This allowed us to estimate the quantity and kind of biogeographical events.Our results suggest a sister relationship between Centropomidae and Sphyraenidae with a common ancestor that originated in the Upper Cretaceous (~78.51 Ma). The biogeographic model BAYAreaLIKE + j indicated speciation in sympatry and dispersal (founder effect) as the primary modes of speciation in the genus Centropomus. The dispersion in the family Centropomidae was estimated from the Tropical Eastern Pacific to the tropical western Atlantic since the Oligocene.The alignment of divergence times with ancestral species distributions suggests a possible synchrony between the current distribution in Centropomus species and the processes of the formation of the Isthmus of Panama during the Miocene. However, the evidence of only two transisthmic pair suggests that this event was not determinant in allopatric interbasin speciation. Furthermore, recent diversification events within each basin imply an influence of post‐closure environmental conditions on the evolution of this group of fishes. [ABSTRACT FROM AUTHOR]

The progressive aridification of the Australian continent, and coincident decline of mesic forest, has been a powerful driver of allopatric and environmental speciation in native species. The relictual mesic forests of the eastern seaboard now harbour a diverse group of endemic fauna, including the wood‐feeding cockroaches of the genus Panesthia, which reached the continent via two separate invasions from Melanesia. The more recent of these colonization events gave rise to a group of five recognized species, occurring in mainland woodlands, sclerophylls and rainforests, as well as the forests and grasslands of the Lord Howe Island Group. Due to limited sampling in molecular studies and doubt regarding the standing taxonomy, there is little certainty about relationships among the species and poor understanding of the effects of ancient climatic change upon their evolution. We undertook a comprehensive phylogenetic analysis of the clade, using complete mitogenomes and nuclear ribosomal markers from nearly all known morphospecies and populations. Our time‐calibrated phylogenetic analyses reveal an additional six unrecognized, highly divergent lineages and suggest that these have arisen primarily through vicariance as rainforests fragmented during Plio‐Pleistocene glacial cycles (2–5 million years ago). Ancestral niche estimations also evidence a tropical rainforest origin for the group, followed by at least three niche transitions into drier forest, including one associated with the singular colonization of the Lord Howe Island Group. Finally, we find evidence of frequent, parallel wing reduction, in potential association with the contraction of forest habitats into small refugia. Our results reiterate the far‐reaching role of ancient aridification in driving speciation, niche expansion and morphological evolution in Australian fauna. [ABSTRACT FROM AUTHOR]

Under allopatric speciation, populations of a species become isolated by a geographic barrier and develop reproductive isolation through genetic differentiation. When populations meet in secondary contact, the strength of evolved reproductive barriers determines the extent of hybridization and whether the populations will continue to diverge or merge together. The yellowhammer (Emberiza citrinella) and pine bunting (E. leucocephalos) are avian sister species that diverged in allopatry on either side of Eurasia during the Pleistocene glaciations. Though they differ greatly in plumage and form distinct genetic clusters in allopatry, these taxa show negligible mitochondrial DNA differentiation and hybridize extensively where they overlap in central Siberia, lending uncertainty to the state of reproductive isolation in the system. To assess the strength of reproductive barriers between taxa, we examined genomic differentiation across the system. We found that extensive admixture has occurred in sympatry, indicating that reproductive barriers between taxa are weak. We also identified a putative Z chromosome inversion region that underlies plumage variation in the system, with the 'pine bunting' haplotype showing dominance over the 'yellowhammer' haplotype. Our results suggest that yellowhammers and pine buntings are currently at a crossroads and that evolutionary forces may push this system towards either continued differentiation or population merging. However, even if these taxa merge, recombination suppression between putative chromosome Z inversion haplotypes may maintain divergent plumage phenotypes within the system. In this way, our findings highlight the important role hybridization plays in increasing the genetic and phenotypic variation as well as the evolvability of a system. [ABSTRACT FROM AUTHOR]

Background: The ability to predict and comprehend molecular interactions offers significant insights into the biological functions of proteins. The interaction between surface protein 47 of Plasmodium falciparum (Pfs47) and receptor of the protein 47 (P47Rec) has attracted increased attention due to their role in parasite evasion of the mosquito immune system and the concept of geographical coevolution between species. The aims of this study were as follows: to apply a bioinformatics approach to investigate the interaction between Pfs47 and P47Rec proteins and to identify the potential binding sites, protein orientations and receptor specificity sites concerning the geographical origins of the vectors and the parasite. Methods: Public sequences of the pfs47 and p47rec genes were downloaded and subsequently filtered to predict functional and structural annotations of the Pfs47-P47Rec complex. Phylogenetic analyses of both proteins were carried out. In addition, the p47Rec gene was subjected to sequencing and subsequent analysis in 2 distinct Anopheles species collected in Honduras. Results: The examination of motifs reveals a significant degree of conservation in pfs47, suggesting that Pfs47 might have undergone recent evolutionary development and adaptation. Structural models and docking analyses supported the theory of selectivity of Plasmodium falciparum strains towards their vectors in diverse geographical regions. A detailed description of the putative interaction between the Pfs47-P47Rec complex is shown. Conclusions: The study identifies coevolutionary patterns between P47Rec and Pfs47 related to the speciation and geographic dispersion of Anopheles species and Plasmodium falciparum, with Pfs47 evolving more recently than P47Rec. This suggests a link between the parasite's adaptability and existing anopheline species across different regions. P47Rec likely has a cytoplasmic localization due to its lack of membrane attachment elements. However, these findings are based on simulations and require validation through methods like cryo-electron microscopy. A significant limitation is the scarcity of sequences in global databases, which restricts precise interaction modelling. Further research with diverse parasite isolates and anopheline species is recommended to enhance understanding of these proteins' structure and interaction. [ABSTRACT FROM AUTHOR]

Simple Summary: The taxonomy of the sinica group of macaques has been unresolved due to inconsistencies between their physical traits and genetic relationships. To clarify this taxonomic issue, we analyzed DNA from previously unsampled populations of the macaques in the Himalayas. Our results revealed that the sinica group consists of seven distinct species, rather than the previously considered six species as the two subspecies of Assamese macaques (Macaca assamensis assamensis and M. a. pelops) are separate candidate species with strong genetic variations. The study also identified Arunachal macaques (M. munzala) in the Shannan area of Xizang Zizhiqu in China. Multiple analyses revealed complex historical patterns of species dispersal and separation, mostly linked to climatic changes during the Quaternary period. We propose a new hypothesis about the sinica group's evolutionary history. Owing to the taxonomic incongruence between the morphological features and genetic relationships of the sinica group of macaques (genus Macaca), the taxonomy of this macaque group has remained inconclusive. We aimed to resolve the taxonomic quandary and improve our understanding of the historical biogeography of the group by including macaque DNA samples from previously unsampled areas in the Himalayas. We sequenced and analyzed three mitochondrial DNA loci [cytochrome b (CYTB), cytochrome oxidase subunit 1 (COI) and D-loop; 2898 bp] for sequence polymorphism, phylogenetics, species delimitation, and ancestral area reconstruction. We confirmed the occurrence of Arunachal macaque (Macaca munzala) on the southern slopes of the Eastern Himalayas in the Xizang Zizhiqu (Tibet Autonomous Region) of China. The results revealed that the sinica group of macaques is a parapatric species group composed of seven distinct species. Phylogenetic and species delimitation analyses revealed that the two previously considered subspecies of Assamese macaques (the eastern subspecies M. assamensis assamensis and the western subspecies M. a. pelops) are two distinct species. The eastern Assamese macaque is a sister species to the Tibetan macaque, whereas the western Assamese macaque and Arunachal macaque are the closest genetic sister species. The sinica group of macaques underwent five vicariance and seven dispersal radiations in the past, which mainly coincided with the Quaternary climatic oscillations between the late Pliocene and the late Pleistocene. By integrating our phylogenetic and ancestral area reconstruction results with findings from previous paleontological and molecular studies, we propose a robust hypothesis about the phylogeography of the sinica group of macaques. [ABSTRACT FROM AUTHOR]

Two subspecies of the Yellow-throated Woodland Warbler Phylloscopus ruficapilla (family Phylloscopidae) have been recognised in South Africa based on the extent and intensity of yellow colouration. Our previous multi-locus population genetic survey across much of the Eastern Cape and southern KwaZulu-Natal provinces, conducted from 2017 to 2023, revealed a single homogenous regional population. That finding, derived from 93 individuals sampled from nine sites—six northeast of the Great Kei River (n = 72) and three to the southwest (n = 21)—did not support a subspecies boundary near the Great Kei River. Here, using 188 publicly archived photographic records for this species in South Africa, we show that the phenotypes of both subspecies are present on either side of this divide. The observed genetic homogeneity and lack of clear phenotypic vicariance suggest that P. ruficapilla is more dispersive than currently appreciated, and that the plumage-based subspecies may not represent significant population-level differences. [ABSTRACT FROM AUTHOR]

Narrow endemism is the core of plant diversity in flora of the Mediterranean Basin, which is among the world's 36 biodiversity hotspots. The Mediterranean genus Kundmannia (Careae, Apioideae) comprises just three species, K. sicula , K. anatolica , and K. syriaca. Notably, K. sicula has a wide distribution from the western Mediterranean to Greece, while K. anatolica and K. syriaca occur only in Turkey's Taurus Mountains, which is a phylogeographical hotspot. Initially, the aim herein was to determine the phylogenetic placement of the genus Kundmannia based on DNA sequences, but it later developed to describing a new genus, Antalia gen. nov. and revealing historical events that acted as drivers in the genetic divergence between Kundmannia and Antalia. Both ribosomal and combined chloroplast multilocus sequences were used to unravel the phylogenetic topology. Toward this aim, morphological characteristics were examined. Based on this, Antalia differs from Kundmannia by its shorter bracteoles and petals, the colour of the petals, and smaller fruits. The phylogenetic results revealed that the genus Kundmannia is nested within the tribe Careae and is not monophyletic. Antalia , which is genetically separate from Kundmannia , is described as a new genus. Detailed morphological descriptions and identification keys are provided. Causes of the genetic disjunction between Antalia and Kundmannia were carefully considered in a time-calibrated phylogenetic framework. The Mediterranean Sea has acted as a relatively effective barrier between these genera since the Messinian salinity crisis. The unwinged mericarps seem to have facilitated the work of the barrier. Historical events during and after the Pliocene and allopatric vicariance seem to have been the most important drivers of evolution between Kundmannia and Antalia and within Antalia. [ABSTRACT FROM AUTHOR]

Biogeographical reconstructions of the Indo-Australian Archipelago (IAA) have suggested a recent spread across the Sunda and Sahul shelves of lineages with diverse origins, which appears to be congruent with a geological history of recent tectonic uplift in the region. However, this scenario is challenged by new geological evidence suggesting that the Sunda shelf was never submerged prior to the Pliocene, casting doubt on the interpretation of recent uplift and the correspondence of evidence from biogeography and geology. A mismatch between geological and biogeographical data may occur if analyses ignore the dynamics of extinct lineages, because this may add uncertainty to the timing and origin of clades in biogeographical reconstructions. We revisit the historical biogeography of multiple IAA taxa and explicitly allow for the possibility of lineage extinction. In contrast to models assuming zero extinction, we find that all of these clades, including plants, invertebrates and vertebrates, have a common and widespread geographic origin, and each has spread and colonized the region much earlier than previously thought. The results for the eight clades re-examined in this article suggest that they diversified and spread during the early Eocene, which helps to unify the geological and biological histories of IAA. [ABSTRACT FROM AUTHOR]

The c. 270 endemic species of Pedicularis in the Himalaya–Hengduan Mountains (HHM) region exhibit high diversity in geographic distribution, elevational range and floral morphology. Many of these, including the species with the longest corolla tubes and beaked galeas, are monophyletic and represent a putative in situ radiation. In this study, we focus on the representative Clade 3 within the HHM region. We integrate the plastid phylogeny of this clade with environmental data and species distributions to infer environmental correlates of species diversity. We estimate macroevolutionary rates and reconstructed ancestral states for geographic ranges and corolla traits, and analyse patterns of range overlap and niche evolution to assess drivers of diversification in the HHM region. Our results show that the region from northwest Yunnan to southwest Sichuan is the centre of diversity for this clade of Pedicularis. Rates of diversification are associated with precipitation and multiple environmental factors. Multiple range expansions from the Sanjiang (Three Parallel Rivers) region, followed by allopatric speciation across the HHM region, contributed to early rapid diversification. Corolla traits are not significantly associated with species diversification. This study highlights the importance of integrated evidence for understanding species diversification dynamics and contributes to our understanding of the origins of the remarkable richness of plant species in the HHM region. [ABSTRACT FROM AUTHOR]

Ever since Alfred Russel Wallace's nineteenth-century observation that related terrestrial species are often separated on opposing riverbanks, major Amazonian rivers have been recognized as key drivers of speciation. However, rivers are dynamic entities whose widths and courses may vary through time. It thus remains unknown how effective rivers are at reducing gene flow and promoting speciation over long timescales. We fit demographic models to genomic sequences to reconstruct the history of gene flow in three pairs of avian taxa fully separated by different Amazonian rivers, and whose geographic ranges do not make contact in headwater regions where rivers may cease to be barriers. Models with gene flow were best fit but still supported an initial period without any gene flow, which ranged from 187 000 to over 959 000 years, suggesting that rivers are capable of initiating speciation through long stretches of allopatric divergence. Allopatry was followed by either bursts or prolonged episodes of gene flow that retarded genomic differentiation but did not fully homogenize populations. Our results support Amazonian rivers as key barriers that promoted speciation and the build-up of species richness, but they also suggest that river barriers are often leaky, with genomic divergence accumulating slowly owing to episodes of substantial gene flow. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusion Species with disjunct geographic distributions provide natural opportunities to investigate incipient or recent allopatric divergence. The combination of both genetic and ecological data may be fruitful to decipher the causes of such patterns: (i) actual vicariance, (ii) successful colonisation from one source to a new range (dispersal, biological introduction) or (iii) parallel convergent evolution.Southern France and Northern Spain.The bee orchid Ophrys aveyronensis (and its two recognised subspecies O. a. subsp. aveyronensis and O. a. subsp. vitorica) displays a disjunct geographic distribution with two subranges separated by 600 km on both sides of the Pyrenees mountain range.As allopatric divergence is often complex to document in the wild, we used a combination of population genomics and ecological niche modelling (ENM) to investigate the causes of this intriguing biogeographic pattern.The population genomic data demonstrate that all the studied populations exhibit similar patterns of genetic diversity and dramatic decrease in effective size compared with the ancestral population. Significant genetic differentiation and reciprocal monophyly exist between populations of the two subranges of O. aveyronensis, despite a very recent divergence time as young as ca. 1500 generations ago. Moreover, paleo‐ENM analyses support that the disjunct geographic distribution of O. aveyronensis is consistent with a range split of a broad ancestral range, contraction and distinct longitudinal and latitudinal shifts in response to climate warming during the Holocene.The congruence of the results obtained from both population genomics and ENM approaches documents how very recent continental allopatric divergence initiated speciation in this system. O. aveyronensis provides a promising opportunity to study the onset of reproductive isolation and parallel evolution following an initial stage of geographic separation in a group with high diversification rate. [ABSTRACT FROM AUTHOR]

Gymnophthalmids are a diverse lineage of Neotropical lizards that present challenges in the understanding of their phylogenetic relationships and biogeographic history. Using a densely sampled phylogeny and distribution data, we investigated their biogeography at the family level. Dividing South and Central America into 12 regions, we tested six biogeographic models considering dispersal-extinction, vicariance, and founder events. Our analysis revealed high taxonomic and phylogenetic endemism in the Andes, Amazon, and Guiana Shield. The best-fit model identified the Guiana Shield as the likely ancestral area of the family, with dispersal events dominating over vicariance. Key areas for species interchange were the Amazon, Northern Andes, and Guiana Shield. The core regions of diversification included the Andes, Amazon, and Guiana Shield, with elevated species richness and biotic interchange events during the Eocene and Oligocene. The Guiana Shield stood out as a stronghold of gymnophthalmid diversity, driven by dispersal rates and ancient lineages. Our findings challenge previous hypotheses about the diversification of these lizards, suggesting a colonization pattern from lowlands to high elevations rather than the South-to-North Speciation Hypothesis for Andean lineages. [ABSTRACT FROM AUTHOR]

The marine gastropod genus Laevilitorina is exclusive to the Southern Hemisphere, with 21 species from southern South America, Antarctica, Australia, New Zealand, and sub-Antarctic Islands. We present a comprehensive revision of Laevilitorina , using molecular and morphological analyses, to address formally the interspecific divergences within the nominal taxon Laevilitorina caliginosa s.l. We confirm the validity of L. caliginosa and Laevilitorina venusta , and we demonstrate that specimens from the Strait of Magellan and Hornos Island constitute four new species here described: Laevilitorina magellanica sp. nov. Laevilitorina pepita sp. nov. Laevilitorina fueguina sp. nov. and Laevilitorina hicana sp. nov. All six species are clearly distinguishable genetically, morphologically, and through radular tooth shape and configurations. Laevilitorina venusta is broadly distributed across the Antarctic Peninsula, South Georgia, and sub-Antarctic Islands (Marion, Crozet, Kerguelen, and Macquarie), whereas L. caliginosa s.s. appears geographically restricted to Cape Horn, the Falkland/Malvinas Islands, and South Georgia. The identification of populations from Macquarie Island as L. caliginosa is dubious; we suggest that these records are likely to pertain to L. venusta. This detailed revision of Laevilitorina , whereby hidden diversity was detected, significantly enriches our knowledge of the evolutionary history of this group. [ABSTRACT FROM AUTHOR]

Recent taxonomic revision of the strikingly ornamented millipedes known as 'dragon millipedes' in the family Paradoxosomatidae, has revealed generic division into six genera. The majority of species are distributed in mainland South-East Asia and each genus is restricted to a well-delimited area. However, their evolutionary history has remained poorly understood, particularly the relationships among genera and their biogeographic distribution. We present a comprehensive and well-resolved molecular phylogeny based on mitochondrial and nuclear genes. A dataset of 256 sequences representing 40 dragon millipede species was newly generated and analysed in order to reveal the relationships and to explore the origin using ancestral range reconstruction. All dragon millipedes were retrieved together as monophyletic, each genus except Hylomus forming a distinct clade with strong statistical values, supporting the previous classification using morphology. A new monotypic genus and new species, Siamaxytes bifurca Srisonchai and Panha gen. nov. et sp. nov. was revealed based on distinct morphological and DNA data. The Tenasserim mountain range was inferred to be the centre of origin of dragon millipedes with a series of subsequent diversifications across mainland South-East Asia. Our analysis provides evidence that both dispersal and vicariance presumably played a role in shaping these millipedes' distribution and diversification. [ABSTRACT FROM AUTHOR]

Unraveling the phylogeographic histories of species remains a key endeavor for comprehending the evolutionary processes contributing to the rich biodiversity and high endemism found in East Asia. In this study, we explored the phylogeographic patterns and demographic histories of three endemic fishfly and dobsonfly species (Neochauliodes formosanus, Protohermes costalis, and Neoneuromus orientalis) belonging to the holometabolan order Megaloptera. These species, which share a broad and largely overlapping distribution, were analyzed using comprehensive mitogenomic data. Our findings revealed a consistent influence of vicariance on the population isolation of Neoc. formosanus and P. costalis between Hainan, Taiwan, and the East Asian mainland during the early Pleistocene, potentially hindering subsequent colonization of the later diverged Neon. orientalis to these islands. Additionally, we unveiled the dual function of the major mountain ranges in East Asia, serving both as barriers and conduits, in shaping the population structure of all three species. Notably, we demonstrated that these co-distributed species originated from Southwest, Southern, and eastern Central China, respectively, then subsequently migrated along multi-directional routes, leading to their sympatric distribution on the East Asian mainland. Furthermore, our results highlighted the significance of Pleistocene land bridges along the eastern coast of East Asia in facilitating the dispersal of mountain-dwelling insects with low dispersal ability. Overall, this study provides novel insight into the synergistic impact of Pleistocene geological and climatic events in shaping the diversity and distribution of aquatic insects in East Asia. [ABSTRACT FROM AUTHOR]

Biogeographers have often been puzzled by several unusual features in the Juan Fernández Islands (JFI) biota. These include the very high endemism density, multiple endemics that are older than the current islands, close biogeographic affinities with the central and West Pacific, and affinities with the diverse Coast Range of central Chile. We review aspects of biogeography in the JFI and the Coast Range in light of recent geological studies. These have examined the mantle below the East Pacific and South America, and have produced radical, new ideas on tectonic history. A long‐lived, intraoceanic archipelago ~9000 km long is now thought to have existed in the East Pacific (passing between the JFI hotspot and mainland Chile) until the mid‐Cretaceous. At this time, South America, which was moving westward with the opening of the Atlantic, collided with the archipelago. The assumption that the JFI biota is no older than its current islands is questionable, as taxa would have survived on prior islands produced at the JFI hotspot. We propose a new interpretation of evolution in the region based on tectonics rather than on island age and incorporating the following factors: the newly described East Pacific Archipelago; a long history for the JFI hotspot; metapopulation dynamics, including metapopulation vicariance; and formation of the Humboldt Current in the Cretaceous. The model accounts for many distinctive features of the JFI and Coast Range biota. [ABSTRACT FROM AUTHOR]

Ctenomys (tuco-tucos) is one of the most speciose genera of mammals, with around 70 described species. Recently, the rate of new species descriptions within the genus Ctenomys has notably increased, primarily due to recent taxonomic revisions and surveys in previously unexplored geographic areas. In this study, utilizing both morphological and molecular evidence, we describe a new species of Ctenomys from northern Argentine Patagonia, confined between the Colorado and Negro rivers. This new species is a member of the Magellanicus group displaying close relationships with other species distributed in northern Patagonia and adjacent regions (C. bidaui, C. miguelchristie, C. pontifex, and C. pulcer). The major rivers in the region (Colorado and Negro rivers) appear to delineate the distributional boundaries of the identified taxa. We therefore propose that rivers, acting as natural barriers to dispersal, have significantly influenced the diversity of Ctenomys in northern extra-Andean Patagonia. [ABSTRACT FROM AUTHOR]

Several diatom species, including Cymbella amplificata, C. janischii and Navicula aurora, are largely restricted to Asia and western North America. These disjunctions likely represent recent long-distance dispersals or chance introductions. The two continents also support clusters of diatom species in several fossil and extant genera. One of these genera, Gomphosinica, is exclusive to the two continents but includes only one species in common. This suggests that these disjunct clusters of species arose from common precursors that underwent radiations while being separated for millennia. The divergence of these lineages likely began more than 25 Ma when island arcs of Asian (Siberian) origin docked on North America. The Asian/North American connection is not restricted to diatoms; vascular plants and dinosaur fossils also exhibit this connection. Differences between diatom floras east and west of the Rocky Mountains, as first noted by Ehrenberg, can be explained by differences in Earth history and geology. Researchers interested in diatom biogeography would do well to become familiar with the tectonic history and geology of their geographic regions of interest. Some cases of ‘invasive’ or ‘alien’ diatoms may simply be that changing conditions allowed existing but latent species to prosper and become apparent to the unaided eye. [ABSTRACT FROM AUTHOR]

Aim Location Taxa Methods Results Main Conclusions Scutigeromorpha is a globally distributed, ancient group of centipedes with at least 400 million years of evolutionary history. We assess the biogeographic history of the order, with a particular focus on the Peninsular Indian Plate (PIP), a Gondwanan fragment. We hypothesize that continental vicariance explains the disjunct distribution of extant scutigeromorphs, that PIP scutigeromorphs are of ancient Gondwanan origins, and that East Gondwana vicariance explains the diversification of the subfamily Thereuoneminae into its Asian and Australian clades.Global.Centipedes, Scutigeromorpha.We use a novel molecular dataset sampled across the PIP and a global sequence database representing the geographic distribution of all families and subfamilies. We employ molecular phylogenetic analyses on two mitochondrial and three nuclear markers, molecular species delimitation and ancestral range estimation to reconstruct biogeographic history.Ancestral scutigeromorphs were likely widely distributed across Gondwana and diverged prior to any continental vicariance. Their subsequent biogeography is shaped by continental vicariance, long‐distance dispersal and jump dispersal, indicating an ability to colonize areas far from their ancestral range. The PIP emerged as the ancestral range of Thereuoneminae, which started diversifying during the Cretaceous Period. Subsequent in‐situ diversification within the PIP and dispersals into Asia, Australia and the Pacific Islands best explained the extant distribution of Thereuoneminae, more so than East Gondwana vicariance.The in‐situ diversification of PIP species and their ancient divergence suggest they represent Gondwanan relicts in a landmass whose biota is primarily dispersal‐driven. A single dispersal event from the PIP generated most of the extant diversity in Australia, another Gondwanan fragment. Furthermore, the discovery of 11 putative species from the PIP and the Andaman Islands, five times more than was known, highlights the Wallacean and Linnean shortfalls in tropical Asia. [ABSTRACT FROM AUTHOR]

The processes of forming lineages undergoing widespread radiations remain a knowledge gap that is fundamental to our understanding of the geographic distributions of species. Although early studies emphasized the importance of dispersal ability and historical migration events, key innovations that promote rapid diversification and/or adaptation to new habitats may also strongly influence distribution ranges. Juniperus is the second largest genus of conifers and is widely distributed throughout the Northern Hemisphere. Here, we used phylogenetic, phenotypic, and climatic data to investigate the contributions of these processes to the wide distribution and rapid diversification of Juniperus. Combining a time-scaled phylogeny and macroevolutionary theory, we show that the key innovations of berry-like seed cones and dioecy promoted the rapid diversification of Juniperus and that increased dispersal ability promoted allopatric speciation. Ecological niches had significant divergence among different clades of Juniperus. Biogeographic results supported multiple long-distance dispersal events and niche variation that contributed to the modern range of Juniperus, while both phenotypic adaptation and ecological opportunity probably drove its distribution range. Our findings suggest that the current widespread distribution is likely the result of significant divergence driven by niche variation in which ecological opportunities from key innovation and phenotypic divergence. Using the macroevolution method, this study shows that key innovations and niche divergence promoted widespread distribution and rapid diversification of Juniperus. [ABSTRACT FROM AUTHOR]

The separation of closely related terrestrial or freshwater species by vast marine barriers represents a biogeographical riddle. Such cases can provide evidence for vicariance, a process whereby ancient geological events like continental rifting divided ancestral geographical ranges. With an evolutionary history extending tens of millions of years, freshwater ecology, and distribution encompassing widely separated southern landmasses, osteoglossid bonytongue fishes are a textbook case of vicariance attributed to Mesozoic fragmentation of the Gondwanan supercontinent. Largely overlooked fossils complicate the clean narrative invoked for extant species by recording occurrences on additional continents and in marine settings. Here, we present a new total-evidence phylogenetic hypothesis for bonytongue fishes combined with quantitative models of range evolution and show that the last common ancestor of extant osteoglossids was likely marine, and that the group colonized freshwater settings at least four times when both extant and extinct lineages are considered. The correspondence between extant osteoglossid relationships and patterns of continental fragmentation therefore represents a striking example of biogeographical pseudocongruence. Contrary to arguments against vicariance hypotheses that rely only on temporal or phylogenetic evidence, these results provide direct palaeontological support for enhanced dispersal ability early in the history of a group with widely separated distributions in the modern day. [ABSTRACT FROM AUTHOR]

Theory links dispersal and diversity, predicting the highest diversity at intermediate dispersal levels. However, the modulation of this relationship by macro-eco-evolutionary mechanisms and competition within a landscape is still elusive. We examine the interplay between dispersal, competition and landscape structure in shaping biodiversity over 5 million years in a dynamic archipelago landscape. We model allopatric speciation, temperature niche, dispersal, competition, trait evolution and trade-offs between competitive and dispersal traits. Depending on dispersal abilities and their interaction with landscape structure, our archipelago exhibits two 'connectivity regimes', that foster speciation events among the same group of islands. Peaks of diversity (i.e. alpha, gamma and phylogenetic), occurred at intermediate dispersal; while competition shifted diversity peaks towards higher dispersal values for each connectivity regime. This shift demonstrates how competition can boost allopatric speciation events through the evolution of thermal specialists, ultimately limiting geographical ranges. Even in a simple landscape, multiple intermediate dispersal diversity relationships emerged, all shaped similarly and according to dispersal and competition strength. Our findings remain valid as dispersal- and competitive-related traits evolve and trade-off; potentially leaving identifiable biodiversity signatures, particularly when trade-offs are imposed. Overall, we scrutinize the convoluted relationships between dispersal, species interactions and landscape structure on macro-eco-evolutionary processes, with lasting imprints on biodiversity. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'. [ABSTRACT FROM AUTHOR]

A good knowledge of the evolutionary history of organisms and an accurate taxonomic framework are keys for efficient biodiversity conservation measures. This is particularly relevant for European butterflies, which are often used as bioindicator organisms and umbrella species for conservation. The Holarctic butterfly genus Agriades includes seven European arctic‐alpine species of which several have a debated taxonomic status. They are localized and allopatric, and at least two of them are of high conservation concern, namely A. aquilo (in Europe, restricted to northern Scandinavia) and A. zullichi (endemic to southern Spain). Despite high conservation value and taxonomic uncertainty, molecular studies on these taxa are limited to DNA barcodes. We investigated the evolutionary history and species delimitation of West Palearctic Agriades using double‐digest RAD sequencing (ddRADseq). Various analyses using genomic data suggested the presence of one species in the glandon species group and one or two in the pyrenaicus species group. The differentiation within the former group (i.e., glandon, aquilo, zullichi) appears to be relatively recent, although the main allopatric populations represent evolutionary significant units (ESUs). Notable geographic structure was found within the pyrenaicus species group, with four allopatric ESUs detected. Wolbachia screening highlighted the presence of several allele combinations, some associated with particular Agriades populations. Genomic data revealed the evolutionary trajectory of European Agriades and a tendency for taxonomic oversplitting within this genus. These findings aid conservation by providing genetic background for region or population prioritization (including ESUs), and for the management of potential population reinforcement or reintroductions. [ABSTRACT FROM AUTHOR]

Species of the genus Eubranchus Forbes, 1838 (Mollusca: Gastropoda: Nudibranchia) are common faunistic elements of boreal benthic ecosystems, associated with hydroid communities. Recent studies have suggested that the widely distributed trans-Arctic E. rupium (Møller, 1842) constitutes a complex of at least three candidate species, but the detailed taxonomy of the complex remains unresolved. The purpose of the present paper is to conduct an integrative taxonomic study including molecular genetic methods (a phylogenetic analysis using COI , 16S rRNA and histone H3 with application of species delimitation methods) and morphological study (light and scanning electron microscopy) of E. rupium and closely related species. The specific aims of this study were to establish the species boundaries, morphological variability, and the phylogeographic structure within this group. The phylogeographic analysis included a TCS -based network analysis, an analysis of molecular variance (AMOVA), divergence time estimations, and ancestral area reconstructions. We demonstrate that specimens initially identified as E. rupium included three distinctive species: the nominal E. rupium with an amphiboreal range, the new species Eubranchus novik sp. nov. from the Sea of Japan, for which a taxonomic description is provided in this paper, and Eubranchus sp. from the northern Kuril Islands, which requires the collection and study of additional material for formal description. Our results confirm the amphiboreal distribution of E. rupium , as no geographic structure was found across Pacific, Arctic and Atlantic populations, and the results of the AMOVA analysis showed no differences between groups of samples from different geographic regions. The divergence of the ' Eubrancus rupium species complex' is estimated from the late Miocene or the Miocene–Pliocene boundary to the late Pliocene. It is hypothesised that the most probable ancestral region for the Eubranchus rupium species complex is the north-western Pacific, and the subsequent speciation likely occurred due to dispersal followed by allopatric speciation. ZooBank: Species of the genus Eubranchus Forbes, 1838 are common in boreal benthic ecosystems. Recent studies suggest the trans-Arctic Eubranchus rupium (Møller, 1842) is a species complex. This paper conducts an integrative taxonomic study of Eubranchus rupium and related species, confirming its amphiboreal distribution. The divergence of the species complex is estimated from the late Miocene or the Miocene–Pliocene boundary to the late Pliocene with the north-western Pacific as the probable ancestral region, followed by dispersal and allopatric speciation. (Image credit: Darya Grishina.) [ABSTRACT FROM AUTHOR]

Inferring the geographic mode of speciation is essential for explaining the generation and assembly of biodiversity, but has been rarely applied to the temperate flora of China. Fagus longipetiolata and F. lucida are a sister pair of beech species with largely overlapping ranges in subtropical China, however, little is known about the geographic mode of speciation and the formation of their sympatric distributions. In this study, we used IMa2 and fastsimcoal2 to simulate the speciation history of the two sisters. On the basis of 11 nuclear loci screened for 27 populations/species, their divergence time was estimated to 8.37 Mya by IMa2, and weak interspecific gene flow was detected. The simulation by fastsimcoal2 found that F. longipetiolata and F. lucida diverged ~8.53 Mya, then came into contact and hybridized at 0.8 Mya. The extended Bayesian skyline plots indicated that F. lucida began demographic expansion prior to the Pleistocene at 3 Mya, whereas F. longipetiolata increased its effective population size during the Quaternary, between 0.8 and 0.5 Mya. Ecological niche analysis and niche modelling showed that the two beeches had subtle niche differentiation and their projected distributions were largely overlapped across the late Quaternary. These results, coupled with well-studied fossil records in Fagus , demonstrate that these two beech species diverged allopatrically at the high latitudes of the Northern Hemisphere, and came into contact and hybridized with each other after successive migrations into subtropical (i.e. warm temperate) China recently. However, the two beeches may have developed strong intrinsic reproductive barriers due to long-term allopatry, allowing them to coexist in subtropical China. Our results illuminate the assembly history of the temperate woody flora in subtropical China, supporting that many relict temperate lineages in subtropical China may have established their populations recently. [ABSTRACT FROM AUTHOR]

The colonization of a novel geographic area is a classic source of ecological opportunity. Likewise, complex microhabitats are thought to promote biodiversity. We sought to reconcile these two predictions when they are naturally opposing outcomes. We assess the macroevolutionary consequences of an ancestral shift from benthic to pelagic microhabitat zones on rates of speciation and phenotypic evolution in North American minnows. Pelagic species have more similar phenotypes and slower rates of phenotypic evolution, but faster speciation rates, than benthic species. These are likely two independent, opposing responses to specialization along the benthic-pelagic axis, as rates of phenotypic evolution and speciation are not directly correlated. The pelagic zone is more structurally homogenous and offers less ecological opportunity, acting as an ecological dead end for minnows. In contrast, pelagic species may be more mobile and prone to dispersal and subsequent geographic isolation and, consequently, experience elevated instances of allopatric speciation. Microhabitat shifts can have decoupled effects on different dimensions of biodiversity, highlighting the need for nuance when interpreting the macroevolutionary consequences of ecological opportunity. [ABSTRACT FROM AUTHOR]

Two alternative hypotheses may explain the origin of Astrophytum coahuilense. One hypothesis is that A. coahuilense is an ancient diploid hybrid derived from interbreeding between A. capricorne and A. myriostigma. An alternative is that A. coahuilense arose via allopatric speciation and its similarity to A. myriostigma in vegetative characters is due to convergent evolution. The two hypotheses are tested, applying univariate analysis and Non-metric Multidimensional Scaling analysis to morphological datasets. Univariate analysis, which is based on 13 vegetative and 10 reproductive characters, shows that the morphology of A. coahuilense is complex, consisting of a combination of vegetative and reproductive characters shared with both A. capricorne and A. myriostigma as well as several intermediate traits. Furthermore, the morphology of A. coahuilense lacks unique, fixed characteristics. Non-metric Multidimensional Scaling analysis of 15 characters (three vegetative and 12 reproductive traits) produced a two-dimensional scatterplot in which the cluster representing A. coahuilense occupies a position intermediate between the clusters of the two parental species along Dimension 1. Thus, both analyses support the hypothesis that Astrophytum coahuilense originated through hybridization between A. capricorne and A. myriostigma. Biological and ecological factors that may have facilitated homoploid hybrid speciation are discussed. [ABSTRACT FROM AUTHOR]

Environmental gradients have the potential to influence genetic differentiation among populations ultimately leading to allopatric speciation. However, environmental gradients can also facilitate hybridization between closely related taxa. We investigated a putative hybrid zone in western Ecuador, involving two polytypic wren species (Aves: Troglodytidae), Campylorhynchus zonatus and C. fasciatus. Our study addressed two primary questions: (1) Is there evidence of population structure and genetic admixture between these taxa in western Ecuador? and (2) What are the relative contributions of isolation by distance and isolation by the environment to the observed genetic differentiation along the environmental gradient in this region? We analyzed 4409 single‐nucleotide polymorphisms (SNPs) from 112 blood samples sequenced using ddRadSeq and a de novo assembly. The optimum number of genetic clusters ranged from 2 to 4, aligning with geographic origins, known phylogenetics, and physical or ecological constraints. We observed notable transitions in admixture proportions along the environmental gradient in western Ecuador between C. z. brevirostris and the northern and southern genetic clusters of C. f. pallescens. Genetic differentiation between the two C. f. pallescens populations could be attributed to an unreported potential physical barrier in central western Ecuador, where the proximity of the Andes to the coastline restricts lowland habitats, limiting dispersal and gene flow, especially among dry‐habitat specialists. The observed admixture in C. f. pallescens suggests that this subspecies may be a hybrid between C. z. brevirostris and C. fasciatus, with varying degrees of admixture in western Ecuador and northwestern Peru. We found evidence of isolation by distance, while isolation by the environment was less pronounced but still significant for annual mean precipitation and precipitation seasonality. This study enhances our understanding of avian population genomics in tropical regions. [ABSTRACT FROM AUTHOR]

Ecological and geographical factors shape the current distribution of species. Analysing their interplay in a phylogenetic framework is key to understand the historical processes that have shaped the evolution of a group. Here, we modelled the ecological niches and geographic distributions of the five species of doraditos (Pseudocolopteryx spp.) to study their biogeographic histories, niche evolution and speciation process in a phylogenetic framework. Our potential distribution models uncovered novel range‐wide distributional patterns and seasonal movements in the doraditos, where four species are migratory with distinct breeding and non‐breeding distributions, and one (P. sclateri) exhibits a complex spatiotemporal distribution indicating nomadism. Ecological niche pairwise comparisons showed that none of the doraditos have equivalent niches and that niche differences are due to species‐specific habitat preferences. Phylogenetically weighted geographical and ecological analyses showed patterns of allopatric speciation and niche lability in the evolution of doraditos. The divergence of P. sclateri seems tied to its tropical‐to‐temperate wetland specialization. The montane P. acutipennis expanded to human‐modified lowlands following speciation, highlighting the need to control for post‐speciational changes in ecological niche comparisons as done here. In turn, P. dinelliana, P. citreola and P. flaviventris showed essentially allopatric breeding distributions, as a product of environmentally mediated divergence during their speciation processes. The distribution and migration data of the recently diverged cryptic sister species P. citreola and P. flaviventris are consistent with two possible speciation scenarios: peripatric speciation and migration dosing speciation. [ABSTRACT FROM AUTHOR]

One of the theoretical tenets of Batesian mimicry is that the distributions of mimics and models should overlap, yet many species of purported mimics occur in allopatry with their models, and this remains a poorly understood area of mimicry theory. We quantified the geographic variation in mimetic accuracy of 2 species of mountain kingsnake--one that is mostly allopatric (Lampropeltis pyromelana) and one that is half sympatric (Lampropeltis knoblochi) with their purported model species (Micruroides euryxanthus). Only L. pyromelana showed significant mimetic breakdown in allopatry. Both species showed a significant positive correlation between latitude and the proportion of black on the dorsal surface, indicating that coloration for these species is likely influenced by climate and thermoregulatory needs. We explore potential differences between these 2 sister species and several non-mutually exclusive explanations for why mimicry persists in allopatry at all, including gene flow, predator migration, and predator vision. considering the limited color vision of some predators, the migration of others, the influences of thermoregulatory needs, and the potential for banded patterns to provide some protective function via flicker fusion, we propose a more nuanced view of the coloration of allopatric coral snake mimics. [ABSTRACT FROM AUTHOR]

Gymnurid rays are found in tropical, subtropical, and temperate regions around the world, where they are associated with sandy or muddy bottoms in coastal areas, being easily distinguished from other rays by the width of the disc. In recent years, the systematics of this family have been revised extensively. However, there has been no comprehensive molecular review of the family based on an adequate sample of species and localities, which may have obscured the presence of distinct evolutionary lineages. The present study was based on samples of 12 of the 13 valid species of the genus Gymnura, which were used for a multilocus reconstruction of the evolutionary history of the family Gymnuridae. Our results indicate the existence of several cryptic gymnurid lineages, within the species Gymnura micrura, Gymnura lessae, Gymnura altavela, and Gymnura poecilura. Also, we indicate that only half of the species that compose the genus are known, as well their conservation status. The analyses also indicate that the gymnurids originated during the Paleocene, with events of dispersal and vicariance occurring through the formation of oceanographic barriers, and species diversification peaking during the Oligocene and Miocene. The results of the present study reinforce the need for a comprehensive revision of the systematics of the family, in particular, the widely distributed species that are considered valid taxa, but may, in fact, represent different cryptic species. The inadequate classification of this cryptic diversity may have negative implications for the development of effective conservation measures. [ABSTRACT FROM AUTHOR]

The Nicobar Bulbul Ixos nicobariensis is an endemic species found across the central Nicobar Islands whose systematic position has been debated for many decades. Its current placement in the genus Ixos is tentative and is based on morphological similarities and geographical affinities to other members of the genus. We used mitochondrial and nuclear markers to examine its phylogenetic relationship to other members of Ixos and Hypsipetes. Our results indicate that the Nicobar Bulbul is sister to members of the genus Hypsipetes, and not Ixos. We further discuss the origin of this species based on the results of our study. [ABSTRACT FROM AUTHOR]

Here, we challenge the origin center of the subfamily Uromastycinae, i.e., eastern or southern Asia, and east to west dispersal toward the Middle East and Africa and suggest that Afro-Arabia is a more probable candidate as the center. The uromastycine clade diverged in Afro-Arabia during the Oligocene, forming the Uromastyx and Saara roots; the Saara root diverged into a northern clade and an eastern clade during Middle Miocene. The northern clade either dispersed towards the Gomphotherium landbridge; the populations that did not cross the landbridge evolved into S. loricata, and the passed ones dispersed eastwards and evolved into S. asmussi; or it extended towards central Iran during the intermittent Tethys seaway connections and/or permanent Tethys seaway closure, and the vicariant Zagros orogeny caused the evolution of S. loricata in the western Zagros and S. asmussi in the eastern Zagros and central Iran. The eastern clade, S. hardwickii, followed a path that formed through the contact of the Indian and Arabian Peninsula continental shelves, amplified by the sea level regression during the Middle Miocene glaciation. [ABSTRACT FROM AUTHOR]

The hyperdiverse orchid genus Bulbophyllum is the second largest genus of flowering plants and exhibits a pantropical distribution with a center of diversity in tropical Asia. The only Bulbophyllum section with a center of diversity inAustralasia is sect. Adelopetalum. However, the phylogenetic placement, interspecific relationships, and spatio-temporal evolution of this section remain largely unclear. To infer broad-level relationships within Bulbophyllum, and interspecific relationshipswithinsect. Adelopetalum, a genome skimmingdatasetwasgenerated for 89 samples, which yielded 70 plastid coding regions and a nuclear ribosomal DNA cistron. For 18 additional samples, Sanger data fromtwo plastid loci (matK and ycf1) and nuclear ITSwere added using a supermatrix approach. The study provided newinsights into broad-level relationships in Bulbophyllum, including phylogenetic evidence for the non-monophyly of sections Beccariana, Brachyantha, Brachypus, Cirrhopetaloides, Cirrhopetalum, Desmosanthes, Minutissima, Oxysepala, Polymeres, and Sestochilos. Section Adelopetalum and sect. Minutissima s.s. formed a highly supported clade that was resolved as a sister group to the remainder of the genus. Divergence time estimations based on a relaxed molecular clock model placed the origin of Bulbophyllum in the Early Oligocene (ca. 33.2 Ma) and sect. Adelopetalumin the Late Oligocene (ca. 23.6 Ma). Ancestral range estimations based on a BAYAREALIKE model identified the Australian continent as the ancestral area of the sect. Adelopetalum. The section underwent crown diversification fromthemid-Miocene to the late Pleistocene, predominantly in continental Australia. At least two independent long-distance dispersal events were inferred eastward from the Australian continent to New Zealand and to New Caledonia from the early Pliocene onwards, likely mediated by predominantly westerly winds of the Southern hemisphere. Retraction and fragmentation of the eastern Australian rainforests from the early Miocene onwards are likely drivers of lineage divergence within sect. Adelopetalum facilitating allopatric speciation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Host contact zone dynamics can be influenced by parasites. • Luscinia nightingales have significantly different haemosporidian prevalence. • Differential prevalence did not change in sympatry versus allopatry. • Community structure was significantly different between hosts, even in sympatry. • Parasites are unlikely to drive contact zone dynamics in nightingales. Parasites are a key driving force behind many ecological and evolutionary processes. Prevalence and diversity of parasites, as well as their effects on hosts, are not uniform across host species. As such, the potential parasite spillover between species can significantly influence outcomes of interspecific interactions. We screened two species of Luscinia nightingales for haemosporidian blood parasites (Plasmodium, Leucocytozoon and Haemoproteus) along an approximately 3000 km transect in Europe, incorporating areas of host distant allopatry, close allopatry and sympatry. We found significant differences in infection rates between the two host species, with common nightingales having much lower parasite prevalence than thrush nightingales (36.7% versus 83.8%). This disparity was mostly driven by Haemoproteus prevalence, which was significantly higher in thrush nightingales while common nightingales had a small, but significantly higher, Plasmodium prevalence. Furthermore, we found no effect of proximity to the contact zone on infection rate in either host species. Despite having lower infection prevalence, common nightingales were infected with a significantly higher diversity of parasite lineages than thrush nightingales, and lineage assemblages differed considerably between the two species, even in sympatry. This pattern was mostly driven by the large diversity of comparatively rare lineages, while the most abundant lineages were shared between the two host species. This suggests that, despite the close evolutionary relationships between the two nightingales, there are significant differences in parasite prevalence and diversity, regardless of the distance from the contact zone. This suggests that spillover of haemosporidian blood parasites is unlikely to contribute towards interspecific interactions in this system. [ABSTRACT FROM AUTHOR]

The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate change. The high species diversity in this mountain system has long been attributed to a complex set of factors, and recent large‐scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago (Mya) to the present. Despite our increasing understanding of the temporal mode of speciation, finer‐scale population‐level investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic speciation. This is largely due to the dearth of organismal sampling among closely related species and populations, spanning the incredible size and topological heterogeneity of this region. Our study dives into these evolutionary dynamics of speciation using genomic and eco‐morphological data of Stellera chamaejasme L. We identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages, suggesting a more recent diversification (~2.67–0.90 Mya), largely influenced by Pleistocene glaciation and biotic factors. These factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the Pleistocene. The study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity, necessitating increased conservation efforts. [ABSTRACT FROM AUTHOR]

The Old-World quails, Coturnix coturnix (common quail) and Coturnix japonica (Japanese quail), are morphologically similar yet occupy distinct geographic ranges. This study aimed to elucidate their evolutionary trajectory and ancestral distribution patterns through a thorough analysis of their mitochondrial genomes. Mitogenomic analysis revealed high structural conservation, identical translational mechanisms, and similar evolutionary pressures in both species. Selection analysis revealed significant evidence of positive selection across the Coturnix lineage for the nad4 gene tree owing to environmental changes and acclimatization requirements during its evolutionary history. Divergence time estimations imply that diversification among Coturnix species occurred in the mid-Miocene (13.89 Ma), and their current distributions were primarily shaped by dispersal rather than global vicariance events. Phylogenetic analysis indicates a close relationship between C. coturnix and C. japonica, with divergence estimated at 2.25 Ma during the Pleistocene epoch. Ancestral range reconstructions indicate that the ancestors of the Coturnix clade were distributed over the Oriental region. C. coturnix subsequently dispersed to Eurasia and Africa, and C. japonica to eastern Asia. We hypothesize that the current geographic distributions of C. coturnix and C. japonica result from their unique dispersal strategies, developed to evade interspecific territoriality and influenced by the Tibetan Plateau's geographic constraints. This study advances our understanding of the biogeographic and evolutionary processes leading to the diversification of C. coturnix and C. japonica, laying important groundwork for further research on this genus. [ABSTRACT FROM AUTHOR]

The Iberian Peninsula constitutes a diversity hotspot with a high number of endemisms, where the land snail genus Iberus is likely the best example. Despite this, its species diversity is still debated as it holds several cryptic species. In the present paper, we use molecular evidence (mitochondrial DNA cytochrome oxidase subunit I) to clarify the position of I. ortizi and three new cryptic species that are described herein: I. giennensis, I. axarciensis and I. antikarianus spp. nov. For this, we sampled 281 sampling points to delimitate a comprehensive geographic mapping of these species. Moreover, we carried out a comprehensive morphometric analysis based on 3205 shells. Our findings show that, morphologically, the three described species overlap in the form of their shells, their morphologies being very similar to other close species with nearby distributions (I. ortizi, I. angustatus and I. marmoratus loxanus). Still, all these species are well-defined by genetic distances, but display allopatric distributions, suggesting that they evolved by allopatric speciation as a consequence of biogeographic isolation. Hence, our findings show insights into the evolution of land snails in southeastern Spain, with implications for their conservation, given that our exhaustive sampling shows that the three species described here have very limited distribution ranges, especially I. antikarianus sp. nov. Our study, moreover, implies an integrated approach to the study of the evolution of land snails, including the sampling of the complete geographic area occupied by the genus, genetic analysis to delimit the actual species range, as well as morphometric analyses to understand the phenotypic differentiation and adaptations of the three new species. [ABSTRACT FROM AUTHOR]

Research on Pleistocene Amazonian refugia has predominantly targeted forest-dwelling taxa, although evidence suggests that endemic species have also evolved in peripheral Amazonian enclaves of open–dry habitats. In Rondônia, Brazil, Tropidurus lizards are restricted to savannah relicts that were once connected to the core Cerrado biome. These populations are currently allocated under Tropidurus oreadicus but hypothesized to comprise allopatric species that evolved in response to landscape changes induced by Pleistocene climatic fluctuations. Phylogenetic analyses support the monophyly of populations from savannah enclaves from Rondônia but place them as distantly related to T. oreadicus. We describe these populations as a new species with unprecedented levels of chromatic polymorphism. A pre-Pleistocene origin is inferred for this new taxon, and dating analysis indicates that Tropidurus species endemic to savannah enclaves diverged from relatives distributed in core open–dry biomes in a non-temporally overlapping fashion. Species distribution models estimate vast climatically suitable areas for the new species during the Last Interglacial, followed by significant contraction during the Last Glacial Maximum, and subsequent expansion and northward displacement towards the Holocene and the present. We conclude that landscape transformations played an important role in the evolution of lizards from enclaves, but their speciation history is temporally deeper than previously thought. [ABSTRACT FROM AUTHOR]

In biogeography, vicariance and long‐distance dispersal are often characterised as competing scenarios. However, they are related concepts, both relying on collective geological, ecological, and phylogenetic evidence. This is illustrated by freshwater fishes, which may immigrate to islands either when freshwater connections are temporarily present and later severed (vicariance), or by unusual means when ocean gaps are crossed (long‐distance dispersal). Marine barriers have a strong filtering effect on freshwater fishes, limiting immigrants to those most capable of oceanic dispersal. The roles of vicariance and dispersal are debated for freshwater fishes of the Greater Antilles. We review three active hypotheses [Cretaceous vicariance, Greater Antilles–Aves Ridge (GAARlandia), long‐distance dispersal] and propose long‐distance dispersal to be an appropriate model due to limited support for freshwater fish use of landspans. Greater Antillean freshwater fishes have six potential source bioregions (defined from faunal similarity): Northern Gulf of México, Western Gulf of México, Maya Terrane, Chortís Block, Eastern Panamá, and Northern South America. Faunas of the Greater Antilles are composed of taxa immigrating from many of these bioregions, but there is strong compositional disharmony between island and mainland fish faunas (>90% of Antillean species are cyprinodontiforms, compared to <10% in Northern Gulf of México and Northern South America, and ≤50% elsewhere), consistent with a hypothesis of long‐distance dispersal. Ancestral‐area reconstruction analysis indicates there were 16 or 17 immigration events over the last 51 million years, 14 or 15 of these by cyprinodontiforms. Published divergence estimates and evidence available for each immigration event suggests they occurred at different times and by different pathways, possibly with rafts of vegetation discharged from rivers or washed to sea during storms. If so, ocean currents likely provide critical pathways for immigration when flowing from one landmass to another. On the other hand, currents create dispersal barriers when flowing perpendicularly between landmasses. In addition to high salinity tolerance, cyprinodontiforms collectively display a variety of adaptations that could enhance their ability to live with rafts (small body size, viviparity, low metabolism, amphibiousness, diapause, self‐fertilisation). These adaptations likely also helped immigrants establish island populations after arrival and to persist long term thereafter. Cichlids may have used a pseudo bridge (Nicaragua Rise) to reach the Greater Antilles. Gars (Lepisosteidae) may have crossed the Straits of Florida to Cuba, a relatively short crossing that is not a barrier to gene flow for several cyprinodontiform immigrants. Indeed, widespread distributions of Quaternary migrants (Cyprinodon, Gambusia, Kryptolebias), within the Greater Antilles and among neighbouring bioregions, imply that long‐distance dispersal is not necessarily inhibitory for well‐adapted species, even though it appears to be virtually impossible for all other freshwater fishes. [ABSTRACT FROM AUTHOR]

Context: Most aquatic macrophytes are ecozone-endemic species, and approximately two-thirds of them have rare occurrence at global scale. These small-range plants are seriously under-studied at macroecological scale, despite their marked vulnerability to extinction through habitat loss and climate change. Aims: To identify global hotspots of endemism and rarity of aquatic macrophytes and examine the factors that resulted in speciation hotspots of macrophytes in some areas of the planet. Methods: We analysed a database of 3499 macrophyte species to locate speciation hotspots and assess the biogeographic and environmental drivers that maintain ecozone-endemic, and globally rare species within their current limited global areas of occupancy. Key results: Ecozone-endemic and globally rare macrophyte species hotspots across the planet showed similar occurrence patterns and drivers among ecozones. Ecozone environmental conditions, particularly harsh environments, influenced macrophyte phylogenetic diversity and structure. Most macrophyte species diversification is recent (<10 million years ago). A negative association with bird-mediated zoochory was seen for endemicity and rarity hotspots. Conclusions: This study identified hotspots of endemicity and rarity, and potential cradle and museum speciation areas. Implications: Our findings could inform global action to conserve the macrophyte diversity of wetlands, and other inland aquatic habitats, across the world. We identified global hotspots of aquatic macrophyte endemism and rarity, and identified factors associated with speciation hotspots of macrophytes in some areas of the planet. We found a total global pool of world-rare macrophytes of 2296 species, each present in <5% of the total world area of inland aquatic habitats. Our findings help identify the locations of potential cradle and museum speciation areas for these plants, that could usefully inform global actions to conserve freshwater macrophyte diversity across the world. This article belongs to the collection Ecology and Management of Aquatic Macrophytes. [ABSTRACT FROM AUTHOR]

BackgroundCommon seadragons (Phyllopteryx taeniolatus, Syngnathidae) are an emblem of the diverse endemic fauna of Australia's southern rocky reefs, the newly recognized "Great Southern Reef." A lack of assessments spanning this global biodiversity hotspot in its entirety is currently hampering an understanding of the factors that have contributed to its diversity. The common seadragon has a wide range across Australia's entire temperate south and includes a geogenetic break over a former land bridge, which has called its status as a single species into question. As a popular aquarium display that sells for high prices, common seadragons are also vulnerable to illegal capture.ResultsHere, we provide range-wide nuclear sequences (986 variable Ultraconserved Elements) for 198 individuals and mitochondrial genomes for 140 individuals to assess species status, identify genetic units and their diversity, and trace the source of two poached individuals. Using published data of the other two seadragon species, we found that lineages of common seadragons have diverged relatively recently (

The Northern Hemisphere temperate forests exhibit a disjunct distributional pattern in Europe, North America, and East Asia. Here, to reveal the promoter of intercontinental disjunct distribution, Fraxinus was used as a model organism to integrate abundant fossil evidence with high-resolution phylogenies in a phytogeographic analysis. We constructed a robust phylogenetic tree using genomic data, reconstructed the geographic ancestral areas, and evaluated the effect of incorporating fossil information on the reconstructed biogeographic history. The phylogenetic relationships of Fraxinus were highly resolved and divided into seven clades. Fraxinus originated in western North America during Eocene, and six intercontinental dispersal events and five intercontinental vicariance events were occured. Results suggest that climate change and vicariance contributed to the intercontinental disjunct distribution pattern of Fraxinus. Moreover, results highlight the necessity of integrating phylogenetic relationship and fossil to improve the reliability of inferred biogeographic events and our understanding of the processes underlying disjunct distributions. A phylogenetic genomics study combining fossil data reveals that climate change led to the intercontinental disjunct distribution pattern of Fraxinus [ABSTRACT FROM AUTHOR]

Interspecific interactions, including host–symbiont associations, can profoundly affect the evolution of the interacting species. Given the phylogenies of host and symbiont clades and knowledge of which host species interact with which symbiont, two questions are often asked: "Do closely related hosts interact with closely related symbionts?" and "Do host and symbiont phylogenies mirror one another?." These questions are intertwined and can even collapse under specific situations, such that they are often confused one with the other. However, in most situations, a positive answer to the first question, hereafter referred to as "cophylogenetic signal," does not imply a close match between the host and symbiont phylogenies. It suggests only that past evolutionary history has contributed to shaping present-day interactions, which can arise, for example, through present-day trait matching, or from a single ancient vicariance event that increases the probability that closely related species overlap geographically. A positive answer to the second, referred to as "phylogenetic congruence," is more restrictive as it suggests a close match between the two phylogenies, which may happen, for example, if symbiont diversification tracks host diversification or if the diversifications of the two clades were subject to the same succession of vicariance events. Here we apply a set of methods (ParaFit, PACo, and eMPRess), whose significance is often interpreted as evidence for phylogenetic congruence, to simulations under 3 biologically realistic scenarios of trait matching, a single ancient vicariance event, and phylogenetic tracking with frequent cospeciation events. The latter is the only scenario that generates phylogenetic congruence, whereas the first 2 generate a cophylogenetic signal in the absence of phylogenetic congruence. We find that tests of global-fit methods (ParaFit and PACo) are significant under the 3 scenarios, whereas tests of event-based methods (eMPRess) are only significant under the scenario of phylogenetic tracking. Therefore, significant results from global-fit methods should be interpreted in terms of cophylogenetic signal and not phylogenetic congruence; such significant results can arise under scenarios when hosts and symbionts had independent evolutionary histories. Conversely, significant results from event-based methods suggest a strong form of dependency between hosts and symbionts evolutionary histories. Clarifying the patterns detected by different cophylogenetic methods is key to understanding how interspecific interactions shape and are shaped by evolution. [ABSTRACT FROM AUTHOR]

Aim: The widespread megadiverse Neotropical snake family Dipsadidae occurs in a large range of diverse habitats. Therefore, it represents an excellent model to study the diversification of Neotropical biota. Herein, by generating a time‐calibrated species‐level phylogeny, we investigate the origin and historical biogeography of Dipsadidae and test if its two main Neotropical subfamilies, Xenodontinae and Dipsadinae, have different geographical origins. Location: Neotropical region. Taxon: Dipsadidae (Serpentes). Methods: We generated a new Bayesian time‐calibrated phylogeny based on published sequences from six genes for 344 species, including 287 species of Dipsadidae. We subsequently estimated ancestral areas of distribution by comparing models in BioGeoBEARS: DEC (subset sympatry, narrow vicariance), DIVALIKE (narrow and wide vicariance), BAYAREALIKE (no vicariance and widespread sympatry), also testing jump dispersal. We also estimated shifts in the diversification of this group using BAMM, exploring possible relationships with its historical biogeography. Results: The best models show that Dipsadidae likely originated approximately 50 million years ago (mya) in Asia. Dispersal was a fundamental process in its historical biogeography. The DEC model with jump dispersal indicated that this family underwent a range extension from Asia and posterior vicariance of North and Central America ancestors. Both Xenodontinae and Dipsadinae originated in Central America and dispersed to South America during Middle Eocene, but did so to different regions (cis and trans‐Andean South America, respectively). Xenodontinae entered cis‐Andean South America around 39 mya and jump dispersed to the West Indies around 33 mya, while Dipsadinae entered trans‐Andean South America multiple times 20–38 mya. The diversification rate decreased through time, except for a clade within Dipsadinae composed of the Dipsadini tribe and the Atractus and Geophis genera. Main Conclusions: Our results show that Dipsadidae has an Asian origin and that the two main Neotropical subfamilies originated in Central America, later dispersing to South America in different time periods. This difference is also reflected in the higher diversification rate for the 'goo‐eaters' in the Dipsadinae subfamily. The current biogeographical patterns of the family Dipsadidae, the most species‐rich snake family in the world, have likely been shaped by complex evolutionary and geological processes such as Eocene land bridges, Andean uplift and the formation of the Panama isthmus. [ABSTRACT FROM AUTHOR]