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1.
Exp Appl Acarol ; 93(3): 537-547, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38985397

RESUMO

Most published data on mite infestation rates in semi-arid regions have been collected over only 3 or 4 months during a specific period of the year. Therefore, the aim of this study was to observe parasite-host dynamics of hygienic and non-hygienic Africanized bee colonies considering environmental factors that may influence Varroa destructor mite infestation rates in a semi-arid region. To this end, the brood puncture method was applied to 37 colonies, forming two groups, namely G1, encompassing 16 hygienic colonies, and G2, comprising 21 non-hygienic colonies. After forming the groups, 300 worker bees from each colony were examined monthly for mite infestations and the data were correlated with climatological records. The monthly infestation average was considered low, below 10%, except in November, when it reached 12.19% ± 6.45. No statistically significant difference was observed for inter-group infestation rates (P > 0.05). When mite infestation rates were associated with climatic variables, they were linked to colony losses (32%) due to swarming. No significant correlations between hygienic behaviour and parasite infestation rates were noted. Nonetheless, these results support the idea that there is no need to apply acaricides for V. destructor control in Brazil.


Assuntos
Dinâmica Populacional , Varroidae , Animais , Abelhas/parasitologia , Varroidae/fisiologia , Brasil , Interações Hospedeiro-Parasita , Clima Desértico
2.
PeerJ ; 9: e12012, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595064

RESUMO

Based on concordant differences in morphology, male advertisement call, and 16S mtDNA barcode distance, we describe a new species of Proceratophrys from southern Amazonia, in the states of Mato Grosso and Pará, Brazil. The new species is most similar to P. concavitympanum and P. ararype but differs from these species by its proportionally larger eyes and features of the advertisement call. Additionally, genetic distance between the new species and its congeners is 3.0-10.4% based on a fragment of the 16S rRNA gene, which is greater than the threshold typically characterizing distinct species of anurans. Using an integrative approach (molecular, bioacoustics, and adult morphology), we were able to distinguish the new species from other congeneric species. The new species is known only from the type locality where it is threatened by illegal logging and gold mining as well as hydroelectric dams.

3.
Acta biol. colomb ; 26(2): 283-286, mayo-ago. 2021. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1355540

RESUMO

ABSTRACT Herein, we report a new record of the milk frog Trachycephalus coriaceus for the Brazilian southern Amazonia and provide an updated geographic distribution map. We collected one specimen of T. coriaceus on 8 november 2016, during a nocturnal survey inside a dense ombrophilous forest in the right bank of the Teles Pires River, municipality ofJacareacanga, southern of Pará State. The record of T. coriaceus to Jacareacanga is the first to the State. The disjoint geographic distribution of this species along de Amazonia may just reflect the paucity of amphibian knowledge throughout this biome and the difficulty to detect this species in the field, given its explosive reproductive behavior.


RESUMEN Aquí, informamos sobre un nuevo registro de la rana lechera Trachycephalus coriaceus para el sur de la Amazonía brasileña y proporcionamos un mapa actualizado de su distribución geográfica. Recolectamos un espécimen de esta especie el 8 de noviembre de 2016, durante un muestreo nocturno dentro de un bosque denso ombrófilo en la margen derecha del río Teles Pires, municipio de Jacareacanga, al sur del estado de Pará. El registro de T. coriaceus en Jacareacanga es el primero en este estado. La distribución geográfica disyunta de esta especie a lo largo de Amazonia puede reflejar la escasez de conocimiento de anfibios en todo este bioma y la dificultad de detectar esta especie en campo, debido a su comportamiento reproductivo explosivo.

4.
PLoS One ; 15(3): e0229971, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187206

RESUMO

The Pristimantis genus (Anura: Craugastoridae) is the most diverse among all vertebrates with 531 described species. The highest diversity occurs in Ecuador (215 species), followed by Colombia (202), Peru (139), Venezuela (60), Brazil (30), Bolivia (17), Guyana (6) Suriname and French Guiana (5). The genus is divided into 11 species groups. Of these, the P. conspicillatus group (containing 34 species), distributed in extreme southeastern Costa Rica, Isla Taboga (Panama), northern South America (from Colombia to eastern Guyana), south Bolivia, and is the best represented in Brazil (16 species). The main characteristics of this group are the tympanic membrane and tympanic annulus distinct (except in P. johannesdei); dorsum smooth or shagreen; dorsal lateral fold present or absent; usually smooth belly, but may be weakly granular in some species; toe V slightly larger than the toe III. Most of the taxonomic inconsistencies in species of Pristimantis could be due to its much conserved morphology and the lack of comprehensive taxonomic evaluations. Thus, an ongoing challenge for taxonomists dealing with the Pristimantis genus is the ubiquitous abundance of cryptic species. In this context, accurate species delimitation should integrate evidences of morphological, molecular, bioacoustics and ecological data, among others. Based on an integrative taxonomy perspective, we utilize morphological, molecular (mtDNA) and bioacoustic evidence to describe four new species of the Pristimantis conspicillatus group from the eastern Amazon basin. Pristimantis giorgii sp. nov. is known from the Xingu/Tocantins interfluve and can be distinguished from the other Pristimantis species of the region by presenting discoidal fold, dorsolateral fold absent, vocalization composed of three to four notes and genetic distance of 7.7% (16S) and 14.8% (COI) from P. latro, the sister and sympatric species with respect P. giorgii sp. nov.. Pristimantis pictus sp. nov. is known to the northern Mato Grosso state, Brazil, and can be distinguished from the other species of Pristimantis by presenting the posterior surface of the thigh with light yellow patches on a brown background, also extending to the inguinal region, vocalization consisting of four to five notes and a genetic distance of 11.6% (16S) and 19.7% (COI) from P. pluvian sp. nov., which occurs in sympatry. Pristimantis pluvian sp. nov. is known to the northern Mato Grosso state, Brazil, and may be distinguished from the other Pristimantis species by having a posterior surface of the thigh reddish and vocalization composed of two notes. Pristimantis moa sp. nov. is known to the northern Tocantins state and southwestern Maranhão state. This species can be distinguished from the other Pristimantis species by possessing slightly perceptible canthal stripe, external thigh surface with dark yellow spots on brown background, vocalization consisting of three to five notes and genetic distance of 2.3-11.7 (16S) and 10.5-23.1 (COI) for the new Pristimantis species of this study.


Assuntos
Distribuição Animal , Anuros/classificação , Filogenia , Animais , Anuros/anatomia & histologia , Anuros/genética , Brasil , América Central , América do Sul
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