RESUMO
In this study we sequenced two mitochondrial (COI and 16S rRNA) and one nuclear (18S rRNA) gene fragment of an introduced muzzled blenny (Omobranchus punctatus) specimen collected from the Orinoco Delta (Gulf of Paria estuary) in Venezuela. This is the first genetic data generated for this species' introduced range in Central and South America, suggesting an introduction from the Indian Ocean.
Assuntos
Espécies Introduzidas , Perciformes/genética , Animais , Oceano Atlântico , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Oceano Índico , Perciformes/classificação , Filogenia , RNA Ribossômico 18S/genética , América do Sul , VenezuelaRESUMO
The Brown Vine Snake, Oxybelis aeneus, is considered a single species despite the fact its distribution covers an estimated 10% of the Earth's land surface, inhabiting a variety of ecosystems throughout North, Central, and South America and is distributed across numerous biogeographic barriers. Here we assemble a multilocus molecular dataset (i.e. cyt b, ND4, cmos, PRLR) derived from Middle American populations to examine for the first time the evolutionary history of Oxybelis and test for evidence of cryptic lineages using Bayesian and maximum likelihood criteria. Our divergence time estimates suggest that Oxybelis diverged from its sister genus, Leptophis, approximately 20.5â¯million years ago (Ma) during the lower-Miocene. Additionally, our phylogenetic and species delimitation results suggest O. aeneus is likely a complex of species showing relatively deep species-level divergences initiated during the Pliocene. Finally, ancestral area reconstructions suggest a Central American origin and subsequent expansion into North and South America.
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Biodiversidade , Colubridae/classificação , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Colubridae/genética , Genoma , Seleção Genética , Especificidade da Espécie , Fatores de TempoRESUMO
Population range expansions and contractions as a response to climate and habitat change throughout the Quaternary are known to have contributed to complex phylogenetic and population genetic events. Speciation patterns and processes in Palearctic buzzards (genus Buteo) are a long-standing example of morphological and genetic data incongruence, attributed to panmixia, habitat range shifts, contact zones, and climate change. Here we assess the systematics, phylogeography and population genetic structure of three nominal species of Palearctic buzzards, Buteo buteo (including B. b. vulpinus), B. rufinus (including B. r. cirtensis) and B. hemilasius. Phylogenetic analyses inferred from mitochondrial data recover B. hemilasius as sister to the sister clades B. r. rufinus and B. buteo complex (B. b. buteo, B. b. vulpinus, but also including B. r. cirtensis). In contrast, we find an unresolved genetic delimitation inferred from four nuclear loci, suggesting an ancestral genetic pool for all species. Time-trees suggest population contractions and expansions throughout the Pleistocene, which likely reflect habitat change and contrasting ecological niche requirements between species. Microsatellite-based extended Bayesian skyline plots reveal relatively constant population sizes for B. hemilasius, B. r. rufinus, and B. b. vulpinus, in contrast to a dramatic population expansion in B. r. cirtensis within the last 3 kya. Overall, our study illustrates how complex population processes over the Late Pleistocene have shaped the patterns of genetic divergence in Palearctic buzzards, due to the joint effects of shared ancestral polymorphisms, population expansions and contractions, with hybridization at contact zones leading to admixture and introgression.
Assuntos
Aves/genética , Variação Genética , Genética Populacional , Paleontologia , Animais , Regiões Árticas , Teorema de Bayes , Mudança Climática , DNA Mitocondrial/genética , Demografia , Marcadores Genéticos , Haplótipos/genética , Repetições de Microssatélites/genética , Mitocôndrias/genética , Taxa de Mutação , Filogenia , Filogeografia , Análise de Sequência de DNA , Especificidade da Espécie , Fatores de TempoRESUMO
BACKGROUND: Defining hidden genetic diversity within species is of great significance when attempting to maintain the evolutionary potential of natural populations and conduct appropriate management. Our hypothesis is that isolated (and eventually small) wild animal populations hide unexpected genetic diversity due to their maintenance of ancient polymorphisms or introgressions. RESULTS: We tested this hypothesis using the Iberian ibex (Capra pyrenaica) as an example. Previous studies based on large sample sizes taken from its principal populations have revealed that the Iberian ibex has a remarkably small MHC DRB1 diversity (only six remnant alleles) as a result of recent population bottlenecks and a marked demographic decline that has led to the extinction of two recognized subspecies. Extending on the geographic range to include non-studied isolated Iberian ibex populations, we sequenced a new MHC DRB1 in what seemed three small isolated populations in Southern Spain (n = 132). The findings indicate a higher genetic diversity than previously reported in this important gene. The newly discovered allele, MHC DRB1*7, is identical to one reported in the domestic goat C. aegagrus hircus. Whether or not this is the result of ancient polymorphisms maintained by balancing selection or, alternatively, introgressions from domestic goats through hybridization needs to be clarified in future studies. However, hybridization between Iberian ibex and domestic goats has been reported in Spain and the fact that the newly discovered allele is only present in one of the small isolated populations and not in the others suggests introgression. The new discovered allele is not expected to increase fitness in C. pyrenaica since it generates the same protein as the existing MHC DRB1*6. Analysis of a microsatellite locus (OLADRB1) near the new MHC DRB1*7 gene reveals a linkage disequilibrium between these two loci. The allele OLADRB1, 187 bp in length, was unambiguously linked to the MHC DRB1*7 allele. This enabled us to perform a DRB-STR matching method for the recently discovered MHC allele. CONCLUSIONS: This finding is critical for the conservation of the Iberian ibex since it directly affects the identification of the units of this species that should be managed and conserved separately (Evolutionarily Significant Units).
Assuntos
Genes MHC da Classe II , Cabras/genética , Alelos , Animais , Genética Populacional , Hibridização Genética , Desequilíbrio de Ligação , Repetições de Microssatélites , Polimorfismo Genético , EspanhaRESUMO
In this study, we report, through molecular identification, the first African records of a digenean trematode parasite of the genus Euryhelmis. We recovered metacercariae encysted in an anuran, the endemic Moroccan painted frog (Discoglossus scovazzi), and a vulnerable caudate, the North African fire salamander (Salamandra algira), from four localities in North Africa (Morocco). Our records go back to the past century and have been confirmed in successive fieldwork seasons thereafter. Metacercarial stages of these parasites require amphibians as the last intermediate host, but the exact identity of the primary hosts and predators of the infected animals in Africa remain unknown. Our searches with basic local alignment search tool (BLAST) from Genbank revealed that hosts were infected by parasites of Euryhelmis costaricensis, which showed almost the same genetic identity (with only one substitution) to previous reports from Costa Rica and Japan, suggesting a recent introduction in Morocco. We proceed to discuss the likely role of introduced mustelids as the potential definitive hosts of trematode adults. Under this assumption, we conclude that the infestation of Discoglossus scovazzi and Salamandra algira might pose a risk to these threatened species.
Assuntos
Anuros/parasitologia , Heterophyidae/isolamento & purificação , Infecções por Trematódeos/epidemiologia , Urodelos/parasitologia , Animais , Heterophyidae/classificação , Heterophyidae/genética , Metacercárias/crescimento & desenvolvimento , Metacercárias/isolamento & purificação , Marrocos/epidemiologia , Infecções por Trematódeos/parasitologiaRESUMO
Coxiella burnetii is the causative agent of Q fever, a zoonotic disease of public health importance. The role of wildlife and their ticks in the epidemiology of C. burnetii in Kenya is unknown. This study analysed the occurrence and prevalence of the pathogen in wildlife and their ticks at two unique wildlife-livestock interfaces of Laikipia and Maasai Mara National Reserve (MMNR) with the aim to determine the potential risk of transmission to livestock and humans. Blood from 79 and 73 animals in Laikipia and MMNR, respectively, and 756 and 95 ixodid ticks in each of the areas, respectively, was analysed. Ticks were pooled before analyses into 137 and 29 samples in Laikipia and MMNR, respectively, of one to eight non-engorged ticks according to species and animal host. Real-time PCR amplifying the repetitive insertion element IS1111a of the transposase gene was used to detect C. burnetii DNA. Although none of the animals and ticks from MMNR tested positive, ticks from Laikipia had an overall pooled prevalence of 2.92% resulting in a maximum-likelihood estimate of prevalence of 0.54%, 95% CI 0.17-1.24. Ticks positive for C. burnetii DNA belonged to the genus Rhipicephalus at a pooled prevalence of 2.96% (maximum-likelihood estimate of prevalence of 0.54%, 95% CI 0.17-1.26). These ticks were Rhipicephalus appendiculatus, R. pulchellus and R. evertsi at pooled prevalence of 3.77, 3.03 and 2.04%, respectively. The presence of C. burnetii in ticks suggests circulation of the pathogen in Laikipia and demonstrates they may play a potential role in the epidemiology of Q fever in this ecosystem. The findings warrant further studies to understand the presence of C. burnetii in domestic animals and their ticks within both study areas.
Assuntos
Coxiella burnetii/isolamento & purificação , Febre Q/veterinária , Carrapatos/microbiologia , Animais , Animais Selvagens/microbiologia , Animais Selvagens/parasitologia , Coxiella burnetii/genética , Humanos , Quênia/epidemiologia , Funções Verossimilhança , Gado/microbiologia , Gado/parasitologia , Febre Q/epidemiologia , Febre Q/transmissão , Inquéritos e Questionários , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterináriaRESUMO
Gene flow is the main force opposing divergent selection, and its effects are greater in populations in close proximity. Thus, complete reproductive isolation between parapatric populations is not expected, particularly in the absence of ecological adaptation and sharp environmental differences. Here, we explore the biogeographical patterns of an endemic ant species, Cataglyphis floricola, for which two colour morphs (black and bicolour) coexist in parapatry throughout continuous sandy habitat in southern Spain. Discriminant analyses of six biometric measurements of male genitalia and 27 cuticular hydrocarbons reveal high differentiation between morphs. Furthermore, the low number of shared alleles derived from nuclear markers (microsatellites) between the morphs at their contact zone suggests the absence of recent gene flow. Mitochondrial DNA (COI) phylogenetic analysis and median-joining networks show that the black morph is basal to the bicolour morph, with unique haplotypes recovered for each morph. Mismatch distribution analysis and Bayesian skyline plots suggest that they are undergoing different demographic changes, with the bicolour and black morphs at demographic equilibrium and expansion, respectively. Thus, our results show complete reproductive isolation between the two colour morphs as evidenced from genetic, chemical and morphological data. We suggest that these divergence events could be explained by historical vicariance during the Pleistocene, in which reproductive traits experienced strong divergent selection between the morphs initiating or culminating speciation.
Assuntos
Formigas/genética , Especiação Genética , Genética Populacional , Filogenia , Animais , Formigas/anatomia & histologia , Teorema de Bayes , DNA Mitocondrial/genética , Fluxo Gênico , Haplótipos , Masculino , Repetições de Microssatélites , Dados de Sequência Molecular , Análise de Sequência de DNA , EspanhaRESUMO
The monospecific genus Tartessiberus was described in the year 2021 including a single species (T.cilbanus). However, its description relied solely on morphological and anatomical data. In the present work, we use a fraction of the mitochondrial DNA cytochrome oxidase subunit I (COI), 16S ribosomal RNA (16S rRNA) and the nuclear large ribosomal subunit (LSU) to clarify its validity through phylogenetic positioning. Knowledge of the distribution of this species is also improved by citing new locations and expanding the geographical range to approximately 200 km2. Additionally, a morphometric analysis of 259 shells is presented for comparisons with shells of the Iberusmarmoratus complex and testing the power of conchological features as a tool for specimen identification. The relatively high conchological variability found for T.cilbanus, together with the discovery of populations with intermediate conchological features between T.cilbanus and other closely related taxa, suggest that the determination of this species should be based on genetic criteria. Our molecular analyses demonstrate that T.cilbanus belongs to the Iberus genus, and thus, we proceed to update its taxonomic status to Iberuscilbanuscomb. nov., and, thus, to consider Tartessiberus from now on as a junior synonym of Iberus.
RESUMO
PURPOSE: Introduced or invasive fish are susceptible to new parasites but can simultaneously carry infectious parasites from their native range towards new hosts. Screening these parasites is key to address the health of fish populations and spread of diseases. METHODS: In this study, we sequenced a Coccidia parasite, for the first time from the blenny Omobranchus sewalli, introduced in the northern coast of Brazil with an Indo-Pacific origin. RESULTS: Only one individual was infected, its genetic sequence matched (over 99%) with two lineages of undetermined species, belonging to the genus Goussia, sequenced from three marine fish species (Mulloidichthys flavolineatus, Lutjanus kasmira, and Selar crumenophthalmus) in Hawaii. CONCLUSIONS: Phylogenetic analysis suggests considerable differentiation between the Goussia detected and other Goussia spp. sequenced from North Atlantic marine fish, thus we cannot exclude the possibly that this parasite was carried by O. sewalli from its native Indo-Pacific range.
Assuntos
Doenças dos Peixes , Parasitos , Perciformes , Animais , Filogenia , Peixes/parasitologia , Perciformes/parasitologia , Brasil , Doenças dos Peixes/parasitologiaRESUMO
Coralsnakes of the genus Micrurus are a diverse group of venomous snakes ranging from the southern United States to southern South America. Much uncertainty remains over the genus diversity, and understanding Micrurus systematics is of medical importance. In particular, the widespread Micrurus nigrocinctus spans from Mexico throughout Central America and into Colombia, with a number of described subspecies. This study provides new insights into the phylogenetic relationships within M. nigrocinctus by examining sequence data from a broad sampling of specimens from Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, and Panama. The recovered phylogenetic relationships suggest that M. nigrocinctus is a species complex originating in the Pliocene and composed of at least three distinct species-level lineages. In addition, recovery of highly divergent clades supports the elevation of some currently recognized subspecies to the full species rank while others may require synonymization.
Assuntos
Peçonhas , Estados Unidos , Filogenia , América Central , Panamá , MéxicoRESUMO
The objective of the present study was to examine the phylogenetic position of Setaria cervi based on sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. A fragment of the cox1 gene from two morphologically identified S. cervi collected from red deer (Cervus elaphus) from Italy were amplified, sequenced, and compared with corresponding sequences of other filarioid nematode species. Phylogenetic studies using Bayesian analysis revealed S. cervi as monophyletic with other Setaria species, confirming S. cervi as a member of the Setaria genus. S. cervi appeared to be sister species to Setaria labiatopapillosa and Setaria digitata. Setaria tundra and Setaria equina, the other two Setaria species presented in the Italian fauna, formed a sister group to the clade consisting of S. cervi, S. labiatopapillosa, and S. digitata. In addition to phylogenetic clarification, our study is the first molecular identification of S. cervi, which may be useful for further molecular identification and differentiation of this filarial worm from other filarioid nematode species, especially in the earlier developmental stages of its life cycle.
Assuntos
Ciclo-Oxigenase 1/genética , Filarioidea/classificação , Filarioidea/genética , Proteínas Mitocondriais/genética , Filogenia , Animais , Análise por Conglomerados , DNA Mitocondrial/química , DNA Mitocondrial/genética , Cervos/parasitologia , Feminino , Filarioidea/isolamento & purificação , Itália , Masculino , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
The development of non-manipulative molecular tools to determine the origin of parasite infections in the animal trade (if infected before their export or import) is of great interest worldwide for both the animal trade industry and for animal welfare. Molecular tools have a wide range of applications, including forensic identification, wildlife preservation and conservation, veterinary public health protection, and food safety. Nonetheless, genetic markers were not reported to detect the source of infection in the animal trade. In this study we tested the applicability of molecular tools to detect the origin of Sarcoptes mite infection of wildebeest imported by the United Arab Emirate (UAE) from Tanzania. Using one multiplex of seven microsatellite markers and control samples from UAE, Kenya and Italy, we demonstrated the usefulness of the multiplex STR-typing as a molecular tool of pivotal interest to help commercialist, authorities, and conservationists, to identify the geographical origin of parasitic infections.
Assuntos
Comércio , DNA/análise , Ciências Forenses/métodos , Reação em Cadeia da Polimerase Multiplex , Doenças Parasitárias em Animais/parasitologia , Parasitologia/métodos , Ruminantes/parasitologia , Sarcoptes scabiei/genética , Escabiose/veterinária , Animais , Antiparasitários/administração & dosagem , Feminino , Marcadores Genéticos , Ivermectina/administração & dosagem , Masculino , Repetições de Microssatélites , Doenças Parasitárias em Animais/diagnóstico , Doenças Parasitárias em Animais/tratamento farmacológico , Doenças Parasitárias em Animais/transmissão , Valor Preditivo dos Testes , Escabiose/diagnóstico , Escabiose/tratamento farmacológico , Escabiose/parasitologia , Escabiose/transmissão , Tanzânia , Emirados Árabes UnidosRESUMO
Natural history museum collections hold extremely rare, extinct species often described from a single known specimen. On occasions, rediscoveries open new opportunities to understand selective forces acting on phenotypic traits. Recent rediscovery of few individuals of Bocourt´s Terrific Skink Phoboscincus bocourti, from a small and remote islet in New Caledonia allowed to genetically identify a species of land crab in its diet. To explore this further, we CT- and MRI-scanned the head of the holotype, the only preserved specimen dated to about 1870, segmented the adductor muscles of the jaw and bones, and estimated bite force through biomechanical models. These data were compared with those gathered for 332 specimens belonging to 44 other skink species. Thereafter we recorded the maximum force needed to generate mechanical failure of the exoskeleton of a crab specimen. The bite force is greater than the prey hardness, suggesting that predation on hard-shelled crabs may be an important driver of performance. The high bite force seems crucial to overcome low or seasonal variations in resource availability in these extreme insular environments. Phoboscincus bocourti appears to be an apex predator in a remote and harsh environment and the only skink known to predate on hard-shelled land crabs.
Assuntos
Braquiúros , Lagartos , Animais , Fenômenos Biomecânicos , Força de Mordida , Dieta , Humanos , Arcada Osseodentária/anatomia & histologia , Comportamento PredatórioRESUMO
Omobranchus punctatus is native to the Indo-Pacific region and invasive in the Atlantic region, currently being considered one of the most widely distributed blenny species. However, recent molecular studies indicated that O. punctatus is a complex of species, with three divergent mtDNA lineages identified to date, stressing the need for a taxonomic revision. In this study, we used an integrative approach, combining morphological and genetic data, to shed light on the taxonomy and distribution of O. punctatus. Moreover, we provide the first genetic records of introduced populations in Brazil and discuss the introduction pattern of this species in this region. Morphological data shows that O. punctatus consists of at least five distinct and geographically restricted species: O. punctatus sensu stricto, O. dispar, O. sewalli, O. cf. kochi, and O. cf. japonicus. Species delimitation analyses performed using the mtDNA data available confirmed that O. punctatus sensu stricto, O. dispar and O. sewalli correspond to different species that started to diverge about 2.6 Mya. Furthermore, O. sewalli was identified as the invasive species colonizing Atlantic shores. The existence of historical oceanographic barriers, such as the emergence of the Sunda Shelf in the Eastern Indian Ocean during the Pleistocene, and the biological traits of these blennies are the most likely factors responsible for their genetic differentiation and subsequent speciation.
Assuntos
Perciformes , Animais , Brasil , DNA Mitocondrial/genética , Espécies Introduzidas , Perciformes/genética , FilogeniaRESUMO
Taxa with vast distribution ranges often display unresolved phylogeographic structures and unclear taxonomic boundaries resulting in hidden diversity. This hypothesis-driven study reveals the evolutionary history of Bufonidae, covering the phylogeographic patterns found in Holarctic bufonids from the West Gondwana to the phylogenetic taxonomy of Asiatic true toads in the Eastern Palearctic. We used an integrative approach relying on fossilized birth-death calibrations, population dynamics, gene-flow, species distribution, and species delimitation modeling to resolve the biogeography of the clade and highlight cryptic lineages. We verified the near-simultaneous Miocene radiations within Western and Eastern Palearctic Bufo, c. 14.49-10.00 Mya, temporally matching with the maximum dust outflows in Central Asian deserts. Contrary to earlier studies, we demonstrated that the combined impacts of long dispersal and ice-age refugia equally contributed to the current genetic structure of Bufo in East Asia. Our findings reveal a climate-driven adaptation in septentrional Eastern Asian Bufo, explaining its range shifts toward northern latitudes. We resolve species boundaries within the Eastern Palearctic Bufo, and redefine the taxonomic and conservation units of the northeastern species: B. sachalinensis and its subspecies.
The east Asian Asiatic toad (also known by the latin name Bufo gargarizans) lives in a wide range of habitats across East Asia including forests, meadows and cultivated land. However, it remains unclear how these toads evolved and became so widespread partly because it has proved difficult for researchers to clearly define the species and what distinguishes it from other closely-related species of toads (collectively known as Bufo toads). Othman et al. combined several bioinformatics techniques to study Asiatic toads and 38 other species of bufonid toads from across the globe. This approach found that Bufo toads first emerged in eastern Asia between 14 and 10 million years ago. This coincides with a point in time when large swathes of land in central Asia turned from adequate to sustain toad populations into desert, suggesting the change in climate prompted the toads to migrate eastwards from central Asia. The Bufo toads then divided into two groups of species: one in mainland East Asia and the other in Japan. Furthermore, the study revealed there is more genetic diversity that is, more variety in the DNA of individuals in Asiatic toads than previously thought. The findings also help to define several other species of Bufo toads more clearly and describe a new toad species restricted to the Korean Peninsula, northeastern China and the Russian Primorye region: the Sakhalin toad (Bufo sachalinensis). This work demonstrates that a large-scale study of many species across the globe can be used to understand how the species evolved and more clearly distinguish one species from another. The findings of Othman et al. will be of interest to both professional and citizen scientists interested in the natural history of Asia. Furthermore, as several species of Bufo toads are in decline in the wild, they provide evidence that may aid future efforts to conserve them.
Assuntos
Evolução Biológica , Bufonidae , Animais , Bufonidae/genética , Fluxo Gênico , Filogenia , FilogeografiaRESUMO
We describe a new species of gymnophthalmid lizard, Oreosaurus bisbali sp. nov., from the Turimiquire Massif in northeastern Venezuela. It is one of three reptile species known to be endemic to the region and the fifth species of Oreosaurus from Venezuela. It can be distinguished from all congeners by a combination of rectangular dorsal scales at midbody, having two scales separating femoral pores medially, and lacking a nasoloreal suture. The new species is likely to be restricted in distribution to the highlands of the Turimiquire Massif, which have been significantly degraded by agriculture.
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Lagartos , Distribuição Animal , Animais , VenezuelaRESUMO
We examine, for the first time, biogeographic patterns in a series of tropical montane coastal systems in northern South America. We use amphibians and reptiles, which constitute the most critical communities based upon the prevalence of endemic taxa, to assess the region's biodiversity. The montane coastal system spans an east-west distance of 925 km. It includes peaks ranging from 549 m to 2765 m above sea level and encompasses the montane complexes of northern Venezuela (including Isla de Margarita), an outlier at Santa Marta (Colombia), and ranges on the islands Trinidad and Tobago. The area supports 14 family level amphibian clades and 23 family level reptile clades. Fieldwork, museum specimen surveys, and a literature review suggest that biodiversity decreases at higher elevations. Here we examine the biogeographic patterns in the region to assess the role of the montane systems as possible refugia. We also look at the possible island and sky island effects using data from altitudes >200 m. At lower elevations, we tabulated 294 species, comprising 112 amphibians and 182 reptiles. About 45% of these taxa are endemic or exclusive to different sub-regions. At mid-elevation montane cloud forests, we find a much-reduced biodiversity with a total of 125 species (66 amphibians and 59 reptiles) exclusive or restricted to the region, and few species shared between systems. We find that biogeographical patterns follow a natural topographic disposition above 200 m in elevations. At the lower elevation cut off, there are 118 species (26 amphibians and 92 reptiles) shared among two or more of the studied mountain systems, suggesting a common origin and dispersal events, despite what seem to be topographic barriers. Biogeographical relationships support a topographic disposition of the region with close associations between the islands of Trinidad and Tobago, the Paria Range and the Turimiquire Massif, and close associations between the Sierra Nevada de Santa Marta and the Sierra de San Luis. Overall, the biogeographic relationships between amphibians and reptiles are similar. Species diversity in the eastern Caribbean region is less rich than in the west. This study includes the first herpetological surveys at the two easternmost mountains (Cerro La Cerbatana and Campeare) belonging to the Paria Range biogeographic unit, and aims to contribute to a better understanding of the rich biodiversity of the region.
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Anfíbios , Biodiversidade , Geografia , Répteis , Altitude , Animais , Florestas , Filogenia , América do SulRESUMO
Recent reviews on sexual dichromatism in frogs included Mannophryne trinitatis as the only example they could find of dynamic dichromatism (males turn black when calling) within the family Aromobatidae and found no example of ontogenetic dichromatism in this group. We demonstrate ontogenetic dichromatism in M. trinitatis by rearing post-metamorphic froglets to near maturity: the throats of all individuals started as grey coloured; at around seven weeks, the throat became pale yellow in some, and more strongly yellow as development proceeded; the throats of adults are grey in males and variably bright yellow in females, backed by a dark collar. We demonstrated the degree of throat colour variability by analysing a large sample of females. The red: green (R:G) ratio ranged from ~1.1 to 1.4, reflecting variation from yellow to yellow/orange, and there was also variation in the tone and width of the dark collar, and in the extent to which the yellow colouration occurred posterior to the collar. Female M. trinitatis are known to be territorial in behaviour. We show a positive relationship between throat colour (R:G ratio) and escape performance, as a proxy for quality. Our field observations on Tobago's M. olmonae showed variability in female throat colour and confirmed that males in this species also turn black when calling. Our literature review of the 20 Mannophryne species so far named showed that all females have yellow throats with dark collars, and that male colour change to black when calling has been reported in eight species; in the remaining 12 species, descriptions of males calling are usually lacking so far. We predict that both dynamic and ontogenetic sexual dichromatism are universal in this genus and provide discussion of the ecological role of dichromatism in this genus of predominantly diurnal, non-toxic frogs, with strong paternal care of offspring.
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Anuros/fisiologia , Caracteres Sexuais , Animais , Anuros/crescimento & desenvolvimento , Comportamento Animal , Cor , Feminino , Masculino , Faringe/fisiologiaRESUMO
[This corrects the article DOI: 10.1371/journal.pone.0223080.].
RESUMO
Tobago is a small island on the southeast edge of the Caribbean Plate with a continental flora and fauna. Using DNA sequences from Genbank, new sequences, and morphological data from the snakes Erythrolamprusepinephalus, E.melanotus, E.reginae, and E.zweifeli, the species status of specimens of a Tobago snake previously considered to be Erythrolamprusreginae was assessed. Erythrolampruszweifeli, long considered a subspecies of E.reginae, was found to be a northern Venezuela-Trinidad endemic and the sister to E.reginae. The trans-Andean species E.epinephalus is shown to be non-monophyletic while the Costa Rican lineage of E.epinephalus is weakly supported as the sister to the Tobago population. The Tobago Erythrolamprus is described as a distinct taxon based upon five specimens from four localities in lower montane rainforest. Much of the new species range includes the Main Ridge Forest Reserve of Tobago, the oldest protected forest in the Western Hemisphere. All known locations fall within a 400-ha area, and its total geographic distribution is likely to be less than 4,566 ha. The restricted distribution of this new snake makes it a likely candidate for threatened status. The new species also becomes another biogeographic link between northern Venezuela and Tobago.