Navegando por Assunto "Morfologia (Animais)"

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Acesso aberto (Open Access)
Contribuições taxonômicas para Palpigera Hebard (Orthoptera:Phalangopsidae) com descrição de novas espécies , novos registros e proposição de um novo gênero para Luzarina
(Universidade Federal do Pará, 2025-04) FRANCO, Lianderson Farias; TAVARES, Gustavo Costa; http://lattes.cnpq.br/1932927205901338; HTTPS://ORCID.ORG/0000-0002-1395-7552; FERNANDES, José Antônio Marin; http://lattes.cnpq.br/6743352818723245; https://orcid.org/0000-0001-7450-5296
The subtribe Luzarina is the most representative in the neotropical region, currently with 128 valid species distributed across 49 genera. In this study, we contribute to the knowledge of the group by describing five new species of Palpigera and a new genus with a new species, Parapalpigera amazonica gen. et sp. nov. The five Palpigera species were identified from 74 specimens collected in different locations in Brazil, including Serra do Cachimbo (PA), Canaã dos Carajás (PA), São José do Rio Claro (MT), Cocalzinho de Goiás (GO), and the Parque Nacional das Sete Cidades (PI). Morphological and internal genitalia analysis revealed that these species differ from other members of the genus in features such as the shape of the palpi, the tenth tergite, metanotal glands, the arrangement of the tympana on the forelegs, vein cells in the tegmina, and the morphology of the phallic complex. These species represent the first records of Palpigera for the northern and northeastern regions of Brazil. Additionally, we describe Parapalpigera amazonica gen. et sp. nov., collected in the Amazon rainforest. This new genus, probably related to Melanotes and Palpigera, is distinguished by its reduced tegmina without a stridulatory apparatus, absence of tympanum, long and thin palpi, shape of the endophallus sclerite, bifid endophallus apodeme, and shape of the female copulatory papilla. These findings expand the taxonomic and biogeographic knowledge of the Luzarina subtribe in the neotropical region.
Acesso aberto (Open Access)
Influência das características morfológicas e do habitat físico sobre a capacidade de dispersão de Odonata em igarapés amazônicos
(Universidade Federal do Pará, 2025-01) PEREIRA, Silvia Rafaela Alves; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029; HTTPS://ORCID.ORG/0000-0002-6188-4386; KOROIVA, Ricardo; http://lattes.cnpq.br/3262687790057613; http://orcid.org/0000-0002-6658-0824
Species' dispersal capacity is directly related to their individual morphological, physiological and behavioral characteristics and to the ecological context in which they live. Species with a lower dispersal capacity tend to be more vulnerable to climate change and more intensive land use. This is due to the loss of vegetation cover and fragmentation leading to a change in habitat connectivity and thermal conditions in the environment. In this study, we investigated the factors affecting the dispersal capacity of adult Odonata in Amazonian streams, focusing on morphological traits and the effects of land use and environmental integrity. We tested the hypotheses: i) body size, thorax volume, and wing base width are positively related to dispersal capacity and wing aspect ratio is negatively related to dispersal capacity; ii) greater forest cover and habitat integrity are negatively related to dispersal capacity, as a larger canopy filters out individuals with lower flight ability. The study was conducted in 12 streams in Barcarena, Pará, Brazil. We used the mark-recapture method and analyzed the data using structural equation modeling. We considered landscape variables (forest formation and pasture), physical habitat variables (channel cover, undergrowth, channel width, habitat integrity index, and temperature), morphological variables (total body length, thoracic volume, and wing aspect ratio) and we used dispersal capacity (distance in meters) as a response variable. 541 individuals were tagged (n=466 Zygoptera e n=75 Anisoptera). The recapture rate was 29% for Zygoptera and 1.4% for Anisoptera. Most of the individuals recaptured were males belonging to the genera Mnesarete, Argia and Hetaerina. Approximately 91% of the individuals moved less than 60 meters. The results, which related only to Zygoptera, partially confirmed the first hypothesis: wing aspect ratio was negatively related to dispersal capacity, suggesting that shorter and wider wings are associated with greater flight ability. However, no direct relationship was found between habitat integrity or forest formation and dispersion, but forest formation and channel width influenced the morphology of individuals' wing aspect ratio. These patterns suggest that genera occurring in forested environments, such as Heteragrion, which have a higher wing aspect ratio, have a lower dispersal capacity, while those adapted to higher temperatures and light availability, such as Mnesarete and Hetaerina, have a lower wing aspect ratio and greater dispersal capacity. We emphasize the vulnerability of individuals with lower dispersal capacity to changes in their aquatic habitats and changes in the surrounding terrestrial landscape due to loss of vegetation cover.