Navegando por Orientadores "SILVEIRA, Orlando Tobias"

Agora exibindo 1 - 5 de 5

Acesso aberto (Open Access)
Filogenia do gênero Mischocyttarus de Saussurre, baseado em caracteres morfológicos e moleculares, e revisão taxonômica do subgênero Megacanthopus Ducke (Hymnoptera, Vespidae, Polistinae)
(Universidade Federal do Pará, 2019-03) FELIZARDO, Sherlem Patrícia de Seixas; SILVEIRA, Orlando Tobias; http://lattes.cnpq.br/9654506257169791; https://orcid.org/0000-0002-5899-199X
Acesso aberto (Open Access)
Morfologia comparada das mandíbulas das fêmeas de vespas da família Sphecidae (Hymenoptera; Apoidea)
(Universidade Federal do Pará, 2016-03-31) SANTOS, Ian Patrick Vilhena dos; SILVEIRA, Orlando Tobias; http://lattes.cnpq.br/9654506257169791
The apoid wasps, represented by Sphecidae; Crabronidae; Heterogynaidae and Ampulicidae are a group of insects that have a large morphological and behavioral diversity. Along with the bees, comprising the superfamily Apoidea, one of the clades that constitute Aculeata. Despite the diversity of apoid wasps, the morphology of the jaw is very neglected, only superficial aspects are taken into consideration in morphological studies. Therefore, the inclusion of this structure as an object of study in order to improve knowledge about this group of wasps is extremely important, especially with respect to Sphecidae family. Therefore, the aim of this study was to analyze the female's jaws in the sphecid wasps describing the morphological variations of each group, taking into consideration the systematic and phylogenetic knowledge of the taxa. Moreover, it was intended to study possible associations between morphological variation patterns of the jaws and the wasps’ biology, as well as producing a list of characters from the mandibular structural elements that can be used in future studies. Only a few genera of each Sphecidae’s subfamily were analyzed in this work, aiming to sample groups in a way that represent the variation of form and habits within the family in the best possible manner. Moreover, Crabronidae and Ampulicidae families were included here as external groups. A total of 23 genera were considered in the analysis, of which 15 belongs to the family Sphecidae and the remaining belonging to the outgroups. The samples analyzed are from the collection of the Museu Paraense Emílio Goeldi (MPEG) and it was also borrowed material from the American Museum of Natural History (AMNH). A survey on the biology, behavior and the use of the jaw in each genus/species was done through consultations on previously published literature, such information was included in the analysis for the study of possible relationships between different lifestyles and use of the jaw. The mandibles were detached from the head of the wasps, described, measured and illustrated. A cladogram of taxa sampled was assembled based on phylogenetic hypotheses already published. The mandibular and biological characters have been optimized on this cladogram, using the criteria of parsimony, to carry out the reconstruction of ancestral states. In this way it was possible to verify the existence of some associations between the morphology of the jaw and the behavior of sphecid wasps.
Acesso aberto (Open Access)
Revisão taxonômica do grupo de espécies de Mischocyttarus (Omega) filiformis (de Saussure, 1854) (Hymenoptera: Vespidae, Polistinae)
(Universidade Federal do Pará, 2017-01-31) BORGES, Rafael Cabral; SILVEIRA, Orlando Tobias; http://lattes.cnpq.br/9654506257169791
Mischocyttarus de Saussure is the only genus in the Mischocyttarini tribe. This tribe is composed by approximately 250 species, being this genus the largest among the Polistinae. M. filiformis (de Saussure) is the type species in the subgenus Omega, and was described based only in the type specimen from Pará state (Brazil). Three related species, posteriorly described, compose the M. filiformis species-group: M. buyssoni (Ducke), M. napoensis Richards e M. omicron Richards. This work aimed to perform a taxonomic revision of the Mischocyttarus filiformis species group based on the analisis of external morphology traits from the type specimens of the previously described species, and in additional specimens from collections in Brazil and in other countries. Four species were redescribed in this study, M. filiformis, M. buyssoni, M. napoensis e M. omicron, and six new species were described, Mischocyttarus sp. nov 1, Mischocyttarus sp. nov 2, Mischocyttarus sp. nov 3, Mischocyttarus sp. nov 4, Mischocyttarus sp. nov 5, Mischocyttarus sp. nov 6, thus increasing to 10 the number of species in this species-group. The geographic distributional records of the species M. filiformis, M. buyssoni e M. omicron is here extended. The male of M. filiformis is described. The nests of M. filiformis, M. buyssoni, Mischocyttarus sp. nov 3, Mischocyttarus sp. nov 4, Mischocyttarus sp. nov 5 are described and additional information about the paralectotypes of M. buyssoni deposited in the MPEG collection is provided.
Acesso aberto (Open Access)
Revisão taxonômica e análise filogenética do gênero Protopolybia Ducke, 1905 com uso de caracteres morfológicos e moleculares (Hymenoptera, Vespidae, Polistinae)
(Universidade Federal do Pará, 2018-05-27) SANTOS JUNIOR, José Nazareno dos; SILVEIRA, Orlando Tobias; http://lattes.cnpq.br/9654506257169791; https://orcid.org/0000-0002-5899-199X
Polistinae is one of the most diverse subfamilies of Vespidae with about 950 species, 25 genera and four tribes. Their representatives are recognized for presenting simple tarsal claws and lacking parategula. Ducke (1905) described two new genera for Polistinae: Protopolybia and Pseudochartergus. Bequaert (1938) reviewed Pseudochartergus recognizing only two species. Bequaert (1944a) made the first revision of Protopolybia, in which he described four new species, and considered P. minutissima and P. sedula as forms of a single species and assigned P. bella as type species of the genus. Richards (1978) performed the second revision of Protopolybia recognizing 23 species and two subspecies. Carpenter and Wenzel (1989), considering inconsistent the diagnostic characters separating Pseudochartergus and Protopolybia, proposed their synonymy, based on the synapomorphic medial posterior process on the metanotum. Carpenter (2011) proposed the synonymy of four species of the genus. Santos-Junior et al. (2015) reviewed the Protopolybia exigua species-group and using morphological characters proposed the first phylogeny for Protopolybia sensu Carpenter & Wenzel (1989). However, there is still a reasonable number of species whose identification is inaccurate. Thus, this project aims to extend the knowledge of the taxonomy and of phylogenetic relationships of the species of Protopolybia using morphological characters complemented with molecular data. For molecular analysis, fragments were isolated of the nuclear and mitochondrial genome - cytochrome subunit I (COI), 28s, 12s and 16s. Such an effort resulted on additional notes for the Protopolybia exigua species-group, with description of a new species. For the P. sedula species-group, all species are redescribed, a new identification key is presented and the genitalia of P. weyrauchi and P. sedula are described. In the P. picteti-emortualis species-group, two new species are described. In the group of species of P. chartergoides, it is proposed the synonymization of a subspecies, and the four valid species are redescribed, as well as the male genitalia of P. chartergoides, P. fuscatus and P. pallidibalteatus. As for the phylogeny of Protopolybia, the monophyly hypothesis of the group of P. chartergoides species is corroborated. Its relative position within Protopolybia is resolved, indicating a closer relationship with the group of P. sedula. On the other hand, in the present analysis the P. exigua group is paraphyletic.
Acesso aberto (Open Access)
Vespas sociais da Floresta Nacional de Caxiuanã, Melgaço, Pará: descrição da fauna numa grade de 25 Km² e compararação entre protocolos de amostragem (Hymenoptera, vespidae)
(Universidade Federal do Pará, 2007) SILVA, Suzanna de Sousa; SILVEIRA, Orlando Tobias; http://lattes.cnpq.br/9654506257169791
Social wasps are remarkable for their complex social organization, the elaborated architecture of the nests, and for their predatory role in terrestrial alimentary chains controlling populations of other insects and arthropods. Inventories of species in Brazil are still reduced in number as well as the efforts for standardization of collecting protocols, thus inhibiting adequate comparison of results. This work consists in a study of a local fauna of social wasps in a parcel of Amazonian terra firm forest in Caxiuanã, Melgaço, PA. The parcel is a 25 km² square, traversed by two orthogonal sets of 5000m tracks, conferring to the study site a grid format. Collecting methods were “Active search for individual and colonies along 1000m transects” and “Malaise traps installed at transect crosses”. Sixty active search samples and 26 Malaise samples were obtained along a discontinuous period of 44 days. Sixty-five species of 12 genera were collected with both methods. Most species were registered by finding individuals, the spotting of nests being relatively rare events (74 nests). Polybia and Mischocyttarus were the most important genera in species number. Agelaia fulvofasciata and Angiopolybia pallens were the most frequent species. The active search method presented a better performance in species discovery (63) than Malaise trap (26). Two subsets of 25 samples were obtained with DIVA-GIS software, both sets summing to 63 species, thus showing that the all-samples total species number could be obtained with a smaller effort, widely distributed across the area. The survey added 21 species to the list of Caxiuanã, now with a total of 100 species, and produced two new species records for Pará state (Polybia brunnea and Mischocyttarus vaqueroi).