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2.
BMC Res Notes ; 17(1): 35, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268047

RESUMO

OBJECTIVE: A reliable taxonomic identification of species from molecular samples is the first step for many studies. For researchers unfamiliar with programming, running a BLAST analysis, filtering, and organizing results for hundreds of sequences through the BLAST web interface can be difficult. Additionally, sequences deposited in GenBank can have outdated taxonomic identification. The use of reliable Reference Sequences Library (RSL) containing accurate taxonomically-identified sequences facilitates this task. Pending the availability of a RSL with the user, we developed a tool that automates the molecular taxonomic identification of sequences. RESULTS: We developed PARSID, a Python script running through the command-line that automates the routine workflow of blasting an input sequence file against the user's RSL, and retrieves the matches with the highest percentage of identity in five steps. PARSID accepts cut-off parameters and supplementary information in a.csv file for filtering the results. The final output is visualized in a spreadsheet. We tested its functioning using 10 input sequences simulating different situations of the molecular taxonomic identification of sequences against an example RSL containing 25 sequences. Step-by-step instructions and test files are publicly available at https://github.com/kokinide/PARSID.git .


Assuntos
Bases de Dados de Ácidos Nucleicos , Publicações , Humanos , Biblioteca Gênica , Pesquisadores , Fluxo de Trabalho
3.
Genome Biol Evol ; 16(1)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38109935

RESUMO

Human activities are accelerating rates of biological invasions and climate-driven range expansions globally, yet we understand little of how genomic processes facilitate the invasion process. Although most of the literature has focused on underlying phenotypic correlates of invasiveness, advances in genomic technologies are showing a strong link between genomic variation and invasion success. Here, we consider the ability of genomic tools and technologies to (i) inform mechanistic understanding of biological invasions and (ii) solve real-world issues in predicting and managing biological invasions. For both, we examine the current state of the field and discuss how genomics can be leveraged in the future. In addition, we make recommendations pertinent to broader research issues, such as data sovereignty, metadata standards, collaboration, and science communication best practices that will require concerted efforts from the global invasion genomics community.


Assuntos
Genômica , Espécies Introduzidas , Humanos , Clima
4.
Zookeys ; 1181: 125-154, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841030

RESUMO

Using an integrative taxonomic approach including genetic and morphological data, we formally describe a new microendemic gecko species belonging to the Paroedurabastardi clade, previously referred to as P.bastardi D. We name this taxon currently known from Anja Reserve and Tsaranoro Valley Forest (south-central Madagascar), as P.manongavatosp. nov. The new species differs from other species of the P.bastardi clade by ≥ 12.4% uncorrected p-distance at the mitochondrial 16S rRNA gene and it forms a monophyletic group in the COI mtDNA phylogenetic tree. It lacks haplotype sharing at the nuclear KIAA1239 and CMOS genes with the other species of the same complex, including the syntopic P.rennerae. Given its limited extent of occurrence and high levels of habitat fragmentation linked to forest clearances and fires, we propose the IUCN Red List Category of Critically Endangered, based on the B1ab(iii) criterion. The conservation value of Anja Reserve and Tsaranoro Valley Forest is remarkable. Preserving the remaining deciduous forest habitat is of paramount importance to protect these narrow-range reptile species.

5.
Sci Rep ; 13(1): 16321, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770544

RESUMO

The host-microbiome community is influenced by several host and environmental factors. In order to disentangle the individual effects of host and environment, we performed a laboratory experiment to assess the effects of the exposure to different water sources on the skin and gut microbiome of two amphibian species (Pelophylax perezi and Bufo spinosus). We observed that the bacterial communities greatly varied with water environment and host identity. Tadpoles of B. spinosus collected from a waterbody with poorer bacterial diversity exhibited a more diverse skin and gut microbiome after exposed to a richer water source. Tadpoles of P. perezi, originally collected from a richer water environment, exhibited less marked alterations in diversity patterns independently of the water source but showed alterations in gut composition. These results highlight that environment alterations, such as the water source, combined with the host effect, impact the microbiome of amphibian species in different ways; the population history (e.g., previous water environment and habitat) of the host species may also influence future alterations on tadpole microbiome.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Larva , Água/farmacologia , Bufonidae , RNA Ribossômico 16S/genética
6.
Zootaxa ; 5319(2): 178-198, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37518239

RESUMO

Frogs of the Blommersia wittei complex are widespread in western and northern Madagascar, and are one of two clades of the family Mantellidae that have colonized the Comoran island of Mayotte. Based on a comprehensive set of DNA sequences of the mitochondrial 16S rRNA gene and the nuclear-encoded RAG1 and SACS genes, integrated with morphological and bioacoustic data, we here analyze the genetic differentiation of populations of this complex across Madagascar. We confirm that a candidate species named B. sp. Ca5 in previous studies represents a genetically well-defined evolutionary lineage distributed over much of western Madagascar, which we describe herein as Blommeria bara sp. nov. based on its molecular and bioacoustic differentiation. Blommersia wittei occurs across northern Madagascar but its type locality Ambanja, at the lower Sambirano river, is very close to the range of another, newly discovered microendemic lineage that was only found at two sites along the upper Sambirano river (here named as candidate species B. sp. Ca12). The B. wittei complex thus provides an example of a clade of closely related Malagasy frogs that contains species widespread over hundreds of kilometers, as well as extreme microendemics. For a full resolution of this species complex, more data need to be collected on the geographical contact among these two lineages, on the morphology and bioacoustics of B. sp. Ca12, and on the north-eastern populations of B. wittei at Sambava, which are weakly differentiated in mitochondrial genes but differ in bioacoustics and possibly in the extent of foot webbing.


Assuntos
Anuros , Evolução Biológica , Animais , Filogenia , Madagáscar , RNA Ribossômico 16S/genética
7.
Animals (Basel) ; 13(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37443897

RESUMO

We analyzed the body length, age structure, and age at sexual maturity of the invasive Asian common toad Duttaphrynus melanostictus from different sites in Toamasina, east Madagascar. We used skeletochronology as a proxy for age estimation, while gonads were histologically analyzed to determine the age of sexual maturity. The analysis of pooled age data from three sites investigated in 2016 showed that both sexes were larger, although not older, than those of native populations. For the individuals from Madagascar, the males were significantly smaller and younger (mean ± SD, SVL: 71.4 ± 1.6 mm; age: 1.8 ± 0.7 years) than the females (SVL: 78.42 ± 1.9 mm; age: 2.7 ± 1.3 years), when the data were pooled, but when the data were analyzed separately for each of the three sites, similar results were obtained only for one site. The oldest recorded male and female were 3 and 6 years old, respectively. Gonadal histology showed that the males and females reach sexual maturity after the first and second years of age, respectively. Further studies are needed to understand if the larger size and faster growth rates observed in the invasive population of D. melanostictus in Madagascar are a consequence of more favorable environmental conditions with respect to the native range (e.g., the availability of larger trophic niches, a lack of competitors, and lower predatory pressure), and we suggest to extend the monitoring of these life history traits to understand how they might influence the invasion.

8.
Sci Rep ; 13(1): 3526, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864075

RESUMO

Invasion dynamics are determined, among other aspects, by the spatial behaviour of invasive populations. The invasive toad Duttaphrynus melanostictus is spreading inland from the eastern coast of Madagascar, causing considerable ecological impacts. Understanding the basic factors determining the spread dynamics can inform management strategies and provide insights into spatial evolutionary processes. We radio-tracked 91 adult toads in three localities along the invasion gradient to determine whether spatial sorting of dispersive phenotypes is occurring, and investigate intrinsic and extrinsic determinants of spatial behaviour. Overall, toads in our study appeared as habitat generalists, and their sheltering behaviour was tied to water proximity, with toads changing shelter more frequently closer to waterbodies. Toads showed low displacement rates (mean = 4.12 m/day) and quite a philopatric behaviour but were able to perform daily movements of over 50 m. We did not detect any spatial sorting of dispersal-relevant traits nor sex- or size-biased dispersal. Our results suggest that toads are more likely to expand their range during the wet season, and that the range expansion is probably dominated by short-distance dispersal at this stage of the invasion, although a future increase in invasion speed is expected, due to the capacity for long-distance movements of this species.


Assuntos
Bufo bufo , Espécies Introduzidas , Animais , Ecologia , Madagáscar
9.
Trends Genet ; 39(7): 545-559, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36801111

RESUMO

The availability of public genomic resources can greatly assist biodiversity assessment, conservation, and restoration efforts by providing evidence for scientifically informed management decisions. Here we survey the main approaches and applications in biodiversity and conservation genomics, considering practical factors, such as cost, time, prerequisite skills, and current shortcomings of applications. Most approaches perform best in combination with reference genomes from the target species or closely related species. We review case studies to illustrate how reference genomes can facilitate biodiversity research and conservation across the tree of life. We conclude that the time is ripe to view reference genomes as fundamental resources and to integrate their use as a best practice in conservation genomics.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Genômica , Genoma
10.
Mol Phylogenet Evol ; 178: 107635, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208694

RESUMO

Most of the unique and diverse vertebrate fauna that inhabits Madagascar derives from in situ diversification from colonisers that reached this continental island through overseas dispersal. The endemic Malagasy Scincinae lizards are amongst the most species-rich squamate groups on the island. They colonised all bioclimatic zones and display many ecomorphological adaptations to a fossorial (burrowing) lifestyle. Here we propose a new phylogenetic hypothesis for their diversification based on the largest taxon sampling so far compiled for this group. We estimated divergence times and investigated several aspects of their diversification (diversification rate, body size and fossorial lifestyle evolution, and biogeography). We found that diversification rate was constant throughout most of the evolutionary history of the group, but decreased over the last 6-4 million years and independently from body size and fossorial lifestyle evolution. Fossoriality has evolved from fully quadrupedal ancestors at least five times independently, which demonstrates that even complex morphological syndromes - in this case involving traits such as limb regression, body elongation, modification of cephalic scalation, depigmentation, and eyes and ear-opening regression - can evolve repeatedly and independently given enough time and eco-evolutionary advantages. Initial diversification of the group likely occurred in forests, and the divergence of sand-swimmer genera around 20 Ma appears linked to a period of aridification. Our results show that the large phenotypic variability of Malagasy Scincinae has not influenced diversification rate and that their rich species diversity results from a constant accumulation of lineages through time. By compiling large geographic and trait-related datasets together with the computation of a new time tree for the group, our study contributes important insights on the diversification of Malagasy vertebrates.


Assuntos
Lagartos , Animais , Filogenia , Serpentes , Tamanho Corporal , Madagáscar
11.
Zootaxa ; 5352(2): 221-234, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-38221452

RESUMO

The Malagasy frog Platypelis mavomavo from Ambolokopatrika in the North East of Madagascar was originally diagnosed based on its bright yellow venter, but only limited information on this species has become available after its initial description in 2003. Several Platypelis specimens with yellow ventral color have been erroneously assigned to this species due to a lack of DNA sequences from the P. mavomavo type series. On the other hand, the candidate species Platypelis sp. Ca10 from Andranomapanga in the Northern Central East of Madagascar with gray ventral color has been defined based on its genetic differentiation from other nominal Platypelis species. Here we study the genetic variation of P. mavomavo and P. sp. Ca10 based on mitochondrial (16S rRNA) and nuclear-encoded (RAG-1) genes, including a newly determined sequence from the P. mavomavo holotype, which was studied using a museomics approach. We find only limited genetic variation among the samples studied, and this variation is unlinked to ventral coloration but instead reflects geographic distribution. We, therefore, conclude that P. sp. Ca10 is a gray-colored variant of P. mavomavo, and that P. mavomavo is rather widespread in the North East and Northern Central East of Madagascar, with populations in areas bordering the North West (Ambohitantely) and Sambirano (Ampotsidy) geographic regions, and the yellow-bellied morph restricted to the North East (Makira, Ambolokopatrika). Due to the range extension of P. mavomavo, the conservation status of the species requires re-assessment.


Assuntos
Anuros , Polimorfismo Genético , Animais , RNA Ribossômico 16S , Filogenia , Anuros/genética
12.
Science ; 378(6623): eabf0869, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36454829

RESUMO

Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique "living laboratory" for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity.


Assuntos
Biodiversidade , Evolução Biológica , Humanos , Biota , Florestas , Madagáscar , Filogenia
13.
Science ; 378(6623): eadf1466, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36454830

RESUMO

Madagascar's unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar's terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.


Assuntos
Biodiversidade , Espécies em Perigo de Extinção , Animais , Humanos , Teorema de Bayes , Biota , Madagáscar , Mamíferos , Plantas
14.
Zootaxa ; 5179(1): 1-61, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36095705

RESUMO

The Lygodactylus madagascariensis species group, constituting the subgenus Domerguella, currently contains five valid species of inconspicuous dwarf geckos from Madagascars humid forests, but at least 18 deep genetic lineages have been revealed by recent molecular studies. Given the high morphological similarity of these lineages, taxonomic resolution of this astonishing diversity requires efforts to correctly delimit species, as well as assigning the available nomina to the species-level lineages identified. We here combine DNA sequences of one mitochondrial and two nuclear-encoded gene fragments with morphometric measurements and scale counts, and report evidence for a species status of most of the previously identified lineages. In particular, we rely on sympatric and often even syntopic occurrence of several of these lineages without evidence for genetic admixture, and consistent with subtle morphological differences. Furthermore, the very high divergences of 7.423.8% pairwise distances in the relatively conserved mitochondrial 16S rRNA gene, combined with a lack of haplotype sharing in the nuclear-encoded genes and differences in scale counts convinced us that most of the other, allopatrically distributed lineages also represent distinct species. We elevate L. madagascariensis petteri to species level and formally name eight new species: L. salvi sp. nov., a species from the Sambirano region in northern Madagascar, previously called L. sp. 8; L. tantsaha sp. nov. (L. sp. 10), a species occurring sympatrically with L. madagascariensis and L. petteri on Montagne dAmbre in far northern Madagascar; L. roellae sp. nov. (L. sp. 17), a species characterized by a striped coloration in all known specimens, from northern Madagascar; L. winki sp. nov. (L. sp. 18), an unstriped species from northern Madagascar but belonging to a subclade mostly distributed in the eastern rainforests of the island; L. ulli sp. nov. (L. sp. 21), a species from the same subclade as L. winki but known only from the Marojejy Massif in the North East; L. fritzi sp. nov. (L. sp. 11), a further species of this subclade from coastal lowlands in the Northern Central East; L. hodikazo sp. nov. (L. sp. 23) known from a single specimen collected at the Tsingy de Bemaraha and therefore the only Domerguella species known from the West region of Madagascar; and L. hapei sp. nov. (L. sp. 26), an enigmatic species from the Sambirano region characterized by a striped pattern on the throat that is otherwise unknown in the subgenus. Three additional deep mitochondrial lineages of Domerguella were identified in our analysis, but could not be further analyzed due to the lack or scarcity of voucher specimens. More field work and collection of voucher specimens is needed to understand their status. Furthermore, the taxonomy of the Domerguella subclade occurring in eastern Madagascar, with three described species (L. guibei, L. miops, L. fritzi), two synonyms (L. septemtuberculatus, Microscalabotes spinulifer) and at least two further deep genetic lineages co-occurring in a relatively small area, requires further revisionary work, possibly aided by target-enrichment sequencing of the respective name-bearing types.


Assuntos
Lagartos , Animais , Anuros , Lagartos/genética , Madagáscar , Filogenia , RNA Ribossômico 16S , Floresta Úmida
15.
Comp Cytogenet ; 16(1): 1-17, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211250

RESUMO

We performed a molecular and cytogenetic analysis on different Mantellinae species and revised the available chromosomal data on this group to provide an updated assessment of its karyological diversity and evolution. Using a fragment of the mitochondrial 16S rRNA, we performed a molecular taxonomic identification of the samples that were used for cytogenetic analyses. A comparative cytogenetic analysis, with Giemsa's staining, Ag-NOR staining and sequential C-banding + Giemsa + CMA + DAPI was performed on eight species: Gephyromantis sp. Ca19, G.striatus (Vences, Glaw, Andreone, Jesu et Schimmenti, 2002), Mantidactylus (Chonomantis) sp. Ca11, M. (Brygoomantis) alutus (Peracca, 1893), M. (Hylobatrachus) cowanii (Boulenger, 1882), Spinomantispropeaglavei "North" (Methuen et Hewitt, 1913), S.phantasticus (Glaw et Vences, 1997) and S. sp. Ca3. Gephyromantisstriatus, M. (Brygoomantis) alutus and Spinomantispropeaglavei "North" have a karyotype of 2n = 24 chromosomes while the other species show 2n = 26 chromosomes. Among the analysed species we detected differences in the number and position of telocentric elements, location of NOR loci (alternatively on the 6th, 7th or 10th pair) and in the distribution of heterochromatin, which shows species-specific patterns. Merging our data with those previously available, we propose a karyotype of 2n = 26 with all biarmed elements and loci of NORs on the 6th chromosome pair as the ancestral state in the whole family Mantellidae. From this putative ancestral condition, a reduction of chromosome number through similar tandem fusions (from 2n = 26 to 2n = 24) occurred independently in Mantidactylus Boulenger, 1895 (subgenus Brygoomantis Dubois, 1992), Spinomantis Dubois, 1992 and Gephyromantis Methuen, 1920. Similarly, a relocation of NORs, from the putative primitive configuration on the 6th chromosome, occurred independently in Gephyromantis, Blommersia Dubois, 1992, Guibemantis Dubois, 1992, Mantella Boulenger, 1882 and Spinomantis. Chromosome inversions of primitive biarmed elements likely generated a variable number of telocentric elements in Mantellanigricans Guibé, 1978 and a different number of taxa of Gephyromantis (subgenera Duboimantis Glaw et Vences, 2006 and Laurentomantis Dubois, 1980) and Mantidactylus (subgenera Brygoomantis, Chonomantis Glaw et Vences, 1994, Hylobatrachus Laurent, 1943 and Ochthomantis Glaw et Vences, 1994).

16.
Trends Ecol Evol ; 37(3): 197-202, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35086739

RESUMO

Progress in genome sequencing now enables the large-scale generation of reference genomes. Various international initiatives aim to generate reference genomes representing global biodiversity. These genomes provide unique insights into genomic diversity and architecture, thereby enabling comprehensive analyses of population and functional genomics, and are expected to revolutionize conservation genomics.


Assuntos
Genoma , Genômica , Biodiversidade
17.
Cell Death Differ ; 29(2): 293-305, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34974533

RESUMO

Huntington's disease is caused by a pathologically long (>35) CAG repeat located in the first exon of the Huntingtin gene (HTT). While pathologically expanded CAG repeats are the focus of extensive investigations, non-pathogenic CAG tracts in protein-coding genes are less well characterized. Here, we investigated the function and evolution of the physiological CAG tract in the HTT gene. We show that the poly-glutamine (polyQ) tract encoded by CAGs in the huntingtin protein (HTT) is under purifying selection and subjected to stronger selective pressures than CAG-encoded polyQ tracts in other proteins. For natural selection to operate, the polyQ must perform a function. By combining genome-edited mouse embryonic stem cells and cell assays, we show that small variations in HTT polyQ lengths significantly correlate with cells' neurogenic potential and with changes in the gene transcription network governing neuronal function. We conclude that during evolution natural selection promotes the conservation and purity of the CAG-encoded polyQ tract and that small increases in its physiological length influence neural functions of HTT. We propose that these changes in HTT polyQ length contribute to evolutionary fitness including potentially to the development of a more complex nervous system.


Assuntos
Doença de Huntington , Peptídeos , Animais , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/patologia , Camundongos , Neurônios/metabolismo , Peptídeos/genética , Peptídeos/metabolismo
18.
Zookeys ; 1126: 1-54, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36763062

RESUMO

A new species of scops-owl (Aves, Strigiformes, Strigidae, Otus) is described from Príncipe Island, São Tomé and Príncipe (Gulf of Guinea, Africa). This species was discovered for science in 2016, although suspicions of its occurrence gained traction from 1998, and testimonies from local people suggesting its existence could be traced back to 1928. Morphometrics, plumage colour and pattern, vocalisations, and molecular evidence all support the species status of the scops-owl from Príncipe, which is described here as Otusbikegila sp. nov. Phylogenetic analyses suggest that this species descended from the first colonisation of the Gulf of Guinea islands, being sister to the clade including the mainland African Scops-Owl O.senegalensis, and the island endemics Sao Tome Scops-Owl O.hartlaubi and Pemba Scops-Owl O.pembaensis. The most diagnostic trait in the field is its unique call which, curiously, is most similar to a distantly related Otus species, the Sokoke Scops-Owl O.ireneae. The new species occurs at low elevations of the old-growth native forest of Príncipe, currently restricted to the south of the island but fully included within Príncipe Obô Natural Park. Otusbikegila sp. nov. takes the number of single-island endemic bird species of Príncipe to eight, further highlighting the unusually high level of bird endemism for an island of only 139 km2.


ResumoDescrevemos uma nova espécie de mocho-de-orelhas ou kitóli (Strigiformes: Strigidae: Otus) da Ilha do Príncipe, São Tomé e Príncipe (Golfo da Guiné, África). Esta espécie foi descoberta para a ciência apenas em 2016, embora suspeitas da sua existência tenham ganho força a partir de 1998, e testemunhos de habitantes locais sobre a sua ocorrência já estarem documentados em 1928. A morfometria, a cor e padrão da plumagem, as vocalizações e dados moleculares demonstram que esta população de mocho no Príncipe é uma espécie nova, que foi batizada de mocho-do-príncipe (lista mundial) ou kitóli-do-príncipe (nome nacional), Otusbikegila sp. nov. As análises filogenéticas indicam que esta espécie descende da primeira colonização das ilhas do Golfo da Guiné, sendo irmã do clado que inclui o mocho-d'ore­lhas-africano O.senegalensis, do continente, o mocho-de-são-tomé (ou kitóli-de-são-tomé) O.hartlaubi e o mocho-de-pemba O.pembaensis, ambos endémicos das ilhas que lhes dão o nome. No campo, a característica mais diagnóstica é o seu canto único que, curiosamente, é mais parecido com o da espécie de Otus mais afastada, o mocho-de-sokoke O.ireneae. A nova espécie ocorre nas zonas baixas da floresta nativa do Príncipe, atualmente restrita ao sul da ilha, mas totalmente inserida no Parque Natural do Obô do Príncipe. Otusbikegila sp. nov. eleva o número de espécies de aves endémicas restritas ao Príncipe para oito, sublinhando ainda mais o nível extremamente elevado de aves endémicas para uma ilha de apenas 139 km2.

19.
PeerJ ; 9: e11532, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249488

RESUMO

Biological invasions are on the rise, with each invader carrying a plethora of associated microbes. These microbes play important, yet poorly understood, ecological roles that can include assisting the hosts in colonization and adaptation processes or as possible pathogens. Understanding how these communities differ in an invasion scenario may help to understand the host's resilience and adaptability. The Asian common toad, Duttaphrynus melanostictus is an invasive amphibian, which has recently established in Madagascar and is expected to pose numerous threats to the native ecosystems. We characterized the skin and gut bacterial communities of D. melanostictus in Toamasina (Eastern Madagascar), and compared them to those of a co-occurring native frog species, Ptychadena mascareniensis, at three sites where the toad arrived in different years. Microbial composition did not vary among sites, showing that D. melanostictus keeps a stable community across its expansion but significant differences were observed between these two amphibians. Moreover, D. melanostictus had richer and more diverse communities and also harboured a high percentage of total unique taxa (skin: 80%; gut: 52%). These differences may reflect the combination of multiple host-associated factors including microhabitat selection, skin features and dietary preferences.

20.
Zootaxa ; 4938(4): zootaxa.4938.4.2, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33756965

RESUMO

The genus Scaphiophryne (Anura: Microhylidae) contains at least nine species that, together with their probable sister genus Paradoxophyla, form the Madagascar-endemic subfamily Scaphiophryninae. Scaphiophryne are robust burrowing frogs with explosive breeding behavior and are characterized by a unique larval morphology, being intermediate between that of filter-feeding and generalized tadpole types. Based on tadpole morphology, the nominal subgenus Scaphiophryne can be distinguished from the subgenus Pseudohemisus, a clade occurring in arid biomes with a largely unsolved taxonomy and nomenclature. Here we combine a comprehensive molecular phylogeny of all scaphiophrynines based on five mitochondrial and two nuclear genes with a re-examination of the name-bearing type specimens of the seven species-level nomina assignable to the subgenus Pseudohemisus. Our molecular phylogeny supports monophyly of the two subgenera and assigns the enigmatic S. matsoko to the subgenus Scaphiophryne. In this subgenus, our analysis confirms all currently accepted species as independent evolutionary lineages based on concordant differentiation in mitochondrial and nuclear genes, and provides evidence for a combination of low mitochondrial divergence, distinct nuclear divergence, and high nuclear heterozygosity. Yet, contrary to previous hypotheses, we do not find evidence of ongoing hybridization. In the subgenus Pseudohemisus we find support for three clearly delimited species-level lineages, one of which contains two deep conspecific lineages that warrant further study. To stabilize the taxonomy in this subgenus, and considering the very poor state of preservation of several type series and the heterogeneity of some of them, we here designate lectotypes for the nomina: Hemisus obscurus Grandidier, 1872; Calophrynus calcaratus Mocquard, 1895; Pseudohemisus verrucosus Angel, 1930; Pseudohemisus longimanus Angel, 1930; and Pseudohemisus longimanus var. melanopleura Angel, 1934. Taxonomically, we accept Scaphiophryne brevis (Boulenger, 1896) as a well-defined species; restrict S. calcarata (Mocquard, 1995) to the southern lineage of the S. calcarata complex; resurrect Hemisus obscurus Grandidier, 1872 (previously considered to be a dubious name or nomen inquirendum) as Scaphiophryne obscura to refer to the western and north-western lineage of the S. calcarata complex; consider Pseudohemisus verrucosus Angel, 1930 as junior synonym of Scaphiophryne brevis; and consider Pseudohemisus longimanus Angel, 1930 and Pseudohemisus longimanus var. melanopleura Angel, 1934 as junior synonyms of Scaphiophryne obscura. Finally, to accelerate taxonomic progress, we (i) outline a set of criteria by which such old and ambiguous nomina can be applied to known lineages, (ii) suggest that the International Code of Zoological Nomenclature should slightly broaden the conditions under which neotypes are to be designated, and (iii) propose to redouble discussions on the introduction of the concept of the epitype to zoology.


Assuntos
Anuros , Ecossistema , Animais , Anuros/genética , Larva , Filogenia
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