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1.
Zookeys ; 1141: 119-148, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234963

RESUMO

The systematic study of biodiversity underlies appropriate inference in most other fields of biological research, yet it remains hampered by disagreements on both theoretical and empirical issues such as the species concept and the operational diagnosis of a species. Both become particularly challenging in those lineages where morphological traits are evolutionarily constrained by their adaptive value. For instance, cryptic organisms often conserve or converge in their external appearance, which hinders the recognition of species boundaries. An integrative approach has been adopted to study microgeographic variation in the leaf-litter lizard Pholidobolusvertebralis and test three predictions derived from the evolutionary species concept. Molecular data provided unambiguous evidence of divergence among the three recovered new clades and a common evolutionary history for each of them. The broadly sympatric clades were indeed diagnosable from externally visible traits, such as head scales, adult size, and sexually dimorphic ventral colouration. Also, they barely overlapped on the phenotypic space that summarised 39 morphometric and meristic traits. These clades are described as three species and an available name is suggested for a recovered fourth clade. The geographic distribution of the new and proximate species suggests a role for elevation on evolutionary divergence; it also raises interesting questions on the speciation pattern of an otherwise underestimated cryptic lineage.

2.
Zootaxa ; 5092(1): 67-84, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35391221

RESUMO

The Terrarana frogs of the genus Pristimantis are acknowledged for their direct development into froglets and for their astonishing species richness, which renders it the anuran genus with the highest number of species. We describe a new species of Pristimantis from the northwestern Andes of Colombia. The species is distributed from an area between 2750-2900 m.a.s.l. in the Mesenia-Paramillo Nature Reserve. Pristimantis postducheminorum sp. nov. differs from other, phylogenetically related, or similar resembling Pristimantis taxa by a striking yellow coloration in the ventral area, dark grey coloration in the concealed surfaces of the thighs and groin, absence of nuptial pads, presence of lateral fringes on fingers, presence of vomerine odontophores triangular in shape from the ventral view, and absence of dorsolateral folds. Molecular phylogenetics place this new species close to P. satagius and therefore within the P. ridens species group. The new species is also phylogenetically close and sympatric with the recently described P. ferwerdai, which further indicates that the Pristimantis fauna has been notoriously underestimated in the Colombian western cloud forests, a fact that should be considered in assessments of environmental impact.


Assuntos
Anuros , Florestas , Animais , Colômbia , Filogenia
3.
Front Genet ; 12: 740940, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721528

RESUMO

Cryptosporidium is a leading cause of waterborne outbreaks globally, and Cryptosporidium hominis and C. parvum are the principal cause of human cryptosporidiosis on the planet. Thanks to the advances in Next-Generation Sequencing (NGS) sequencing and bioinformatic software development, more than 100 genomes have been generated in the last decade using a metagenomic-like strategy. This procedure involves the parasite oocyst enrichment from stool samples of infected individuals, NGS sequencing, metagenomic assembly, parasite genome computational filtering, and comparative genomic analysis. Following this approach, genomes of infected individuals of all continents have been generated, although with striking different quality results. In this study, we performed a thorough comparison, in terms of assembly quality and purity, of 100+ de novo assembled genomes of C. hominis. Remarkably, after quality genome filtering, a comprehensive phylogenomic analysis allowed us to discover that C. hominis encompasses two lineages with continental segregation. These lineages were named based on the observed continental distribution bias as C. hominis Euro-American (EA) and the C. hominis Afro-Asian (AA) lineages.

4.
Zootaxa ; 5057(3): 1-28, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34811206

RESUMO

The Neotropics harbors a tremendous diversity of cockroaches yet their evolutionary history is largely unknown. We reconstructed for the first time the phylogeny of the Neotropical genus Xestoblatta Hebard using mitochondrial and nuclear genes from 12 species distributed in Central America and northern South America. Additionally, we conducted a morphological analysis of external characters and male genitalia. In the phylogenetic analysis we recovered the genus Xestoblatta as non-monophyletic, resulting in three unrelated lineages. From the morphological variability described here, we identified three different morphological groups matching the phylogenetic results. The phylogenetic relationships of the three lineages within the Blattellidae were partially resolved. Lineage 1 was nested within a supported clade corresponding to the tribes Blattellini + Symplocini, while lineages 2 and 3 nested within the clade corresponding to the tribe Pseudomopini. Based on our results, we propose to divide Xestoblatta (sensu lato) into three monophyletic genera: Antroxestoblatta gen.n., Sinatablatta gen.n., and Xestoblatta (sensu stricto). We also describe a new species Sinatablatta magdalenensis sp.n. and propose a taxonomic rearrangement for Xestoblatta (sensu lato).


Assuntos
Blattellidae , Animais , Genitália , Masculino , Filogenia , Análise de Sequência de DNA
5.
Zootaxa ; 4838(1): zootaxa.4838.1.4, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33056833

RESUMO

Continuous sampling in well studied areas may lead to new amphibian species discoveries, because population dynamics allow rare species to go unnoticed for years. Based on recent sampling of frogs in the northeastern region of Colombia, here we provide genetic, morphological, and bioacoustics evidence to support the description of a new species of the genus Pristimantis. Phylogenetic analysis suggests the new species is a member of the P. lacrimosus species group, a clade of 25 species that is highly diverse in Ecuador and Peru. This new species is more closely related to allopatric species from Peru and Guyana (i.e. P. olivaceus, P. pluvialis, P. pulchridormientes, and an undetermined Pristimantis). The new species has green-yellow coloration and a remarkable brown interocular band, which is unusual in the genus and which inspired the epithet. Pristimantis zorro sp. nov. has only been found at one locality at 1860 m s.a.l., on the eastern flank of the northern Cordillera Central in Department of Antioquia, Colombia. The new species inhabits the ecotone between the humid cloud forest and open areas. Repeated visits to the type locality suggest high variation in population abundance and/or species detection, because we have occasionally observed many individuals in briefs periods of times. In addition, we discuss the biogeographical and systematic implications of our species discovery.


Assuntos
Anuros , Animais , Colômbia , Filogenia
6.
Zootaxa ; 4648(3): zootaxa.4648.3.8, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31716940

RESUMO

The frogs of the genus Pristimantis are recognized for their characteristic reproductive mode and for their incredible diversity of species, becoming the genus with the highest number of species within tetrapod vertebrates. We describe here a new species of Pristimantis from the northwestern Andes of Colombia. The species was found between 2000-2500 m.a.s.l., mostly within moss hanging of tree branches in a tropical cloud forest. It can be easily distinguished from other Pristimantis species of the western Andes by the unique black and white patterning in the ventral surface and the flanks, the hourglass-shaped dorsal folds, and the prominent conical tubercles on eyelids, heels, and outer edge of tarsus. A phylogenetic analysis further supports its status of a lineage reciprocally monophyletic to P. satagius and separated by a genetic distance of 0.03; the latter species bear whitish rather than predominantly black ventral coloration. To the best of our knowledge, this species is only known from the 2,500 ha nature reserve Mesenia-Paramillo, despite other research on this area of the country. Therefore, the species is declared vulnerable while new evidence on its distribution range is accumulated.


Assuntos
Anuros , Florestas , Animais , Colômbia , Filogenia
7.
Genome Biol Evol ; 11(11): 3123-3143, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31642474

RESUMO

Convergent evolution is often documented in organisms inhabiting isolated environments with distinct ecological conditions and similar selective regimes. Several Central America islands harbor dwarf Boa populations that are characterized by distinct differences in growth, mass, and craniofacial morphology, which are linked to the shared arboreal and feast-famine ecology of these island populations. Using high-density RADseq data, we inferred three dwarf island populations with independent origins and demonstrate that selection, along with genetic drift, has produced both divergent and convergent molecular evolution across island populations. Leveraging whole-genome resequencing data for 20 individuals and a newly annotated Boa genome, we identify four genes with evidence of phenotypically relevant protein-coding variation that differentiate island and mainland populations. The known roles of these genes involved in body growth (PTPRS, DMGDH, and ARSB), circulating fat and cholesterol levels (MYLIP), and craniofacial development (DMGDH and ARSB) in mammals link patterns of molecular evolution with the unique phenotypes of these island forms. Our results provide an important genome-wide example for quantifying expectations of selection and convergence in closely related populations. We also find evidence at several genomic loci that selection may be a prominent force of evolutionary change-even for small island populations for which drift is predicted to dominate. Overall, while phenotypically convergent island populations show relatively few loci under strong selection, infrequent patterns of molecular convergence are still apparent and implicate genes with strong connections to convergent phenotypes.


Assuntos
Boidae/genética , Deriva Genética , Variação Genética , Seleção Genética/genética , Animais , Belize , Evolução Molecular , Genética Populacional , Genoma , Honduras , Ilhas , Fenótipo , Filogenia
8.
Ecology ; 100(5): e02685, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30847899

RESUMO

Species traits provide a strong link between an organism's fitness and processes at community and ecosystem levels. However, such data remain scarce for amphibians in the Neotropics. Colombia is the country with the highest number of threatened amphibians and the second greatest number of amphibian species worldwide. We present a data set containing eight morphological traits for 4,623 museum specimens of the seven largest collections in the country corresponding to 293 species of 14 families. The number of measured specimens per species ranged from 1 to 118 individuals with a median of 8 individuals per species. Overall, this database gathered morphological information for 37.6% of Colombian anuran diversity. Species measured were mainly distributed in the high Andean forest, the páramo, and wetland ecosystems, and was part of a national initiative led by the Instituto Alexander von Humboldt. The morphological traits were selected on the basis of their role in species' responses to environmental variability and their contributions to ecosystem processes. These traits were related to habitat use, (forearm length, tibia length, femur length, foot length, and foot webbing), predation and food chains (head width and mouth width), and nutrient recycling (snout-vent length). We expect this data set will be used in studies on functional diversity in amphibians and the development of conservation planning for these taxa. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.

9.
Primates ; 60(1): 93-102, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30413903

RESUMO

The use of GPS telemetry has been a reliable research tool for the study of primate biology in recent years. Although in the past technological restrictions limited its use mainly to large primates, recent improvements in battery size make it possible to use this technology for small species. We used GPS devices for monitoring two adult white-footed tamarins (Saguinus leucopus) from a free-ranging group, and assessed its applicability for recording spatial and ecological data. GPS devices were operational for 66 and 85 days, recording 221 positions (36.6% acquisition rate; 73% of which were highly accurate) and 3195 activity values for both individuals. Depending on the estimation method, we calculated the home range size for the group to be 19.4 and 22.9 ha, which were within the range for the species in other localities. The animals were active each day for 11 h, with high activity during the early morning. The monkeys showed a constant and alternate use of four sleeping sites with a limited reuse of the same site on consecutive nights. These daily activity and sleeping site use patterns are similar to those reported for other Saguinus species. Based on the kind and quality of the data recorded, we consider GPS telemetry to be an efficient and advantageous method for tracking and obtaining ecological information from S. leucopus. In comparison to other data collection methods, GPS telemetry required fewer personnel and less time commitment to record data without compromising the accuracy of the spatial and activity information we obtained.


Assuntos
Ecologia/métodos , Sistemas de Informação Geográfica/instrumentação , Comportamento de Retorno ao Território Vital , Saguinus/fisiologia , Animais , Colômbia , Espécies em Perigo de Extinção , Feminino , Masculino
10.
Zootaxa ; 4461(3): 359-380, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30314073

RESUMO

We describe a new species of Dendrobatidae from the eastern flank of the northern Central Cordillera in Colombia and assign it to the recently named genus Leucostethus. We also assess the phylogenetic status of the Colostethus fraterdanieli "complex" which according to our phylogenetic inference, is closely related to the new species. We use morphological, genetic and bioacoustic evidence to describe the new species and to expand the phylogeny of the genus Leucostethus. As a result, we transfer the content of C. fraterdanieli "complex" to Leucostethus. The new species differs from the Leucostethus fraterdanieli "complex" species by having white testes, straight pale ventrolateral stripes and high genetic divergence (17% in Cyt-b). According to our results, the genus Leucostethus is distributed in the western Amazonia from Ecuador and Peru, and both the northern Andes and Pacific lowlands in Colombia. We also found that L. fraterdanieli sensu stricto is restricted from mid (1600 m.a.s.l) to high (2500 m.a.s.l) elevation on the northern Central Cordillera in Antioquia. Extensive geographic sampling and more thorough morphological and bioacoustic examination need to be considered to solve the genetic clusters observed in the Leucostethus fraterdanieli "complex".


Assuntos
Anuros , Filogenia , Animais , Colômbia , Equador , Peru
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