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1.
Zookeys ; 1212: 217-240, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39318671

RESUMO

True poison-dart frogs (Phyllobates, Dendrobatidae) evolved the ability to secrete batrachotoxins, the most powerful alkaloids known to date. The genus comprises five species whose systematics, at first glance, appeared clear. The most derived clade would include two Colombian species (P.terribilis and P.bicolor) with the highest toxicity, the largest body size, and predominantly yellow body colouration. The other three species (P.aurotaenia, P.vittatus, and P.lugubris) are less toxic on average, have smaller size, and are predominantly black with bright dorsolateral stripes. Recent research has revealed the existence of two major lineages among the three Colombian species. The northern lineage appears to result from a complex evolutionary history, including perhaps introgression among yellow and black taxa. The southern lineage instead revealed the existence of new clades closely related to P.terribilis, black and yellow, that arguably deserve their recognition as new species. Here, available evidence is combined to support the erection of southern populations of P.aurotaenia as a new highly toxic species, sister to P.terribilis, and much closer to it than to any other yellow or black-bodied species, Phyllobatessamperi sp. nov. Their common ancestor is sister to an additional yellow species, which we also describe here as Phyllobatesbezosi sp. nov. Both new species can be externally diagnosed using colouration. Our previous and current analyses also suggest the existence of additional taxa and corroborate multiple transitions in colouration across these hypertoxic taxa.


ResumenLas verdaderas ranas de dardo venenoso (género Phyllobates) evolucionaron la capacidad de secretar batracotoxinas, los alcaloides más poderosos que se conocen hasta hoy. El género comprende cinco especies, cuya taxonomía parecía clara a primera vista. El clado más derivado incluye dos especies colombianas (P.terribilis and P.bicolor) con la mayor toxicidad, mayor tamaño y coloración predominantemente amarilla. Las otras tres especies (P.aurotaenia, P.vittatus and P.lugubris) son en general menos tóxicas, menores en tamaño y predominantemente negras con conspicuas manchas dorsolaterales.Una reciente investigación confirmó la existencia dos linajes mayores entre las tres especies colombianas. El del norte parece ser el producto de una historia evolutiva compleja, incluyendo quizás introgresión entre especies amarillas y negras. El del sur reveló en cambio la existencia de nuevos clados filogenéticamente cercanos a P.terribilis, uno negro y dos amarillos, que requieren reconocimiento formal como nuevas especies. Esta investigación combina la evidencia disponible para apoyar el reconocimiento de las poblaciones del sur de P.aurotaenia como una nueva especie negra, hermana de P.terribilis, y mucho más cercana a ella que a las otras especies negras o amarillas, Phyllobatessamperi sp. nov. Su ancestro común es a su vez el grupo hermano de una especie adicional, amarilla, que también describimos como Phyllobatesbezosi sp. nov. Las dos nuevas especies pueden ser externamente reconocidas por la coloración. Nuestros análisis previos y actuales también sugieren la existencia de otras especies no descritas y corroboran la existencia de múltiples transiciones de coloración en la evolución de las especies hipertóxicas.

2.
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.

3.
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
4.
Zootaxa ; 5150(2): 217-238, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-36095751

RESUMO

The genus Anadia (family Gymnophthalmidae) consists of 19 species. It has remained almost taxonomically stable for decades, scarcely observed, in addition to being one of the less sampled gymnophthalmid genera with respect to molecular phylogenies. New Anadia species are discovered at a relatively low pace, and few specimens are found in the field, probably due to the arboreal habits of many low and mid elevation species. We describe here a new species of Anadia from the cloud forests of northwestern Colombia: the new species is easily diagnosed by the combination of shape and imbrication of dorsal scales, very large body size, the largest within its group, and large and non-overlapping number of longitudinal scale rows around midbody. We also tested the phylogenetic position of the recently described and geographically close A. antioquensis. A phylogenetic analysis based on four genomic regions recovered the new species as sister to A. buenaventura, whereas A. antioquensis was reassigned to the genus Riama. The new species is currently known from only three specimens, collected throughout eight years within less than 5 ha of the Mesenia-Paramillo Nature Reserve. Although its apparent rarity may be due to secretive habits, the species is provisionally declared vulnerable, while new information is available. To stimulate further research on this genus, we also compiled and present here the comparable information on the distribution and morphology of Anadia species. Altogether, the results stress the urge for a new review of the genus with the help of molecular data.


Assuntos
Lagartos , Animais , Tamanho Corporal , Colômbia , Florestas , Filogenia
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