945 resultados para Reactive species of oxygen


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A positive coefficient of association (affinity) between Runchomyia reversa and Anopheles cruzii and high (0.38) index were observed, probably due to the similar breeding places (bromeliads) and to landing habits. Furthermore, a high (0.92) index of association between Oc. scapularis and Wyeomyia incaudata, with low coefficient of association was observed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

INTRODUCTION: Triatoma pseudomaculata and T. wygodzinskyi (Hemiptera: Reduviidae: Triatominae) are two Brazilian vectors of Chagas disease. The first is an arboricolous species in sylvatic environment and considered a vector of T. cruzi in peridomestic structures; the second, a rupicolous species in the wild environment of no epidemiological importance. In order to test the assumption that sister species share biological traits, comparative studies of their development cycle and blood ingestion were conducted. METHODS: Eggs laid by five field females of each species were randomly selected. The nymphs were observed daily and fed on mice weekly. The time required to pass through the different stages to adulthood was recorded in days. The triatomines were weighed individually before and after feeding. The mortality rate according to each nymphal stage was calculated. RESULTS AND CONCLUSIONS: Analysis of the results shows that they display only minor biological differences even though they exhibit a distinct ecology. This suggests that the biological traits are important criteria to determine the relationship between species.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

INTRODUCTION: Besides mosquito species adapted to urban environments (Culex quinquefasciatus, Aedes aegypti and Aedes albopictus), only 15 species of Anopheles had been recorded in the State of Pernambuco. METHODS: Human-landing mosquitoes were collected in Dois Irmãos Park, in Recife. RESULTS: The first report for the state of Haemagogus janthinomys, an important vector of yellow fever virus, and 14 other species, including Trichoprosopon lampropus, a first reported for Brazil. CONCLUSIONS: The mosquito fauna in the area is diversified and has potential medical and veterinary importance.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Introduction In Triatominae, reproductive efficiency is an important factor influencing population dynamics, and a useful parameter in measuring a species' epidemiological significance as a vector of Trypanosoma cruzi (Chagas, 1909). The reproductive efficiency of triatomines is affected by food availability; hence, we measured and compared the effects of feeding frequency on the reproductive parameters of Triatoma patagonica (Del Ponte, 1929) and Triatoma infestans (Klug, 1934), and the effects of starvation on T. patagonica. Methods Couples from both species were fed weekly, or every 3 weeks; in addition, females in couples of T. patagonica were not fed. Each couple was observed weekly and reproductive efficiency was assessed on the following parameters: fecundity (eggs/female), fertility (eggs hatched/eggs laid), initiation and end of oviposition, initiation of mating, number of matings/week, and number of reproductive weeks. Relative meal size index (RMS), blood consumption index (CI), and E values (eggs/mg blood) were also calculated. Results Changes in feeding frequency affected the reproductive parameters of T. patagonica only, with a decrease in fecundity and number of reproductive weeks for those fed every 3 weeks, or not fed. The reproductive period, RMS index, and CI were lower for T. patagonica than T. infestans. However, despite the lower fecundity of T. patagonica, this species required less blood to produce eggs, with an E values of 2 compared to 2.94 for T. infestans. Conclusions Our results suggest that the differences in fecundity observed between species reflect the availability of food in their natural ecotopes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Introduction Biological collections are depositories of information on different species and contribute to the knowledge, protection, conservation and maintenance of biodiversity. Methods A list of triatomine species currently included in the Collection of Chagas Disease Vectors (FIOCRUZ-COLVEC) was prepared from the database made available by the Reference Center on Environmental Information. Results COLVEC curatorship houses 4,778 specimens of triatomines, of which 811 come from other American countries (Argentina, Bolivia, Colombia, Costa Rica, the United States of America, Guatemala, Mexico, Peru, Uruguay and Venezuela) and 3,967 are autochthonous from Brazil. Altogether, 56 species of Chagas disease vectors are represented in the COLVEC: two species of the Tribe Cavernicolini Usinger, 1944; fifteen species of the tribe Rhodniini Pinto, 1926, of which 12 are of the genus Rhodnius and 3 are of the genus Psamolestes; and 39 species of the tribe Triatomini Jeannel, 1919, represented by the genus Dipetalogaster, two species of the genus Eratyrus, two of the genus Meccus, seven of the genus Panstrongylus and 27 of the genus Triatoma. Conclusions This list provides important data on the diversity of triatomines currently included in COLVEC, including the expanded area of Panstrongylus lutzi occurrence in the municipalities Pirapora and Januária, State of Minas Gerais. The maintenance and expansion of the collection ensures the preservation of biodiversity and further studies.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Four new species of Neidawnaria are described, and compared with other members of the genus. Keys and geographical distribution are given for all nem species and the wings of two other species are illustrated.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Abarema piresii Barneby & Grimes is described from the Brazilian states of Amazonas and Pará. The species is illustrated an tis relationships are discussed. Two kindred species are incidentally transferred from Pithecellobium to Abarema as A. curvicarpa (Irwin) and A. moniliformis (Ducke) Barneby & Grimes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new species, Hibiscus amazonicus, is described from the Amazon Basin. Characters distinguishing the new species from its nearest relatives presented.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new Amazonian species of Justicia, J. zarucchii from the region oif the Rio Abacaxis is described, illustrated, and compared with J. schultesii and J. gutierrezii, its closest relatives.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In order, to place the new taxa. of Ficus found in Amazonian Brazil and the Guianas (see Vázquez Avila, Berg & Kooy, Acta Amazonica, fallowing article in this volume) in a taxonomic and phytogeographic framework, a key to the taxa provisionally recognized for Amazonia and the Guianas is presented and fallowed by a concise treatment of these taxa.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Phithecellobium prancei, related to T. simabifolium Benth. and P. spruceanum Benth., is described and figured from specimens collected on white sand savannas along rio Aracá in northern Amazonas, Brazil. Its relationships within sect. Samanea ser. Coriaceae Benth., a group due for generic segregation from Pithecellobium sens. lat., are discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The work conelete of a survey of the mvaewe plants which appeared during the first six months of seedling stage in foreet plantations of second and third rotation, in the Jari area, Brazil. The resulting list showed two types of invasives: (1) true weeds - those cosmopolitan species that are typical of disturbed habitats; and (2) pioneer species - those which were probably remnants from the original natural vegetation of the studied area.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A new species of Calanoid copepod, Rhacodiaptomus besti,is described from material collected in the Igarapé São Pedro, Rio Jamari, State of Rondônia, and Lago Amanã, Rio Japurá, State of Amazonas, in Western Amazonia. A detailed morphological analysis of the species was undertaken in order to provide a basis for future studies on inter and intrageneric relationships.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A critical analysis of the type collections of 39 species names of Paspalum L. (Poaceae: Paniceae) from Brazil described by Swallen is presented along with comments based on more recent gatherings of the species. Eighteen new synonyms are proposed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The new species Notiobia glabrata, N. maxima and N. pseudolimbipennis are described. A key to the 11 Notiobia (s.str.) species known from Brazil, data about the distribution of each species and taxonomical remarks are provided. Notiobia parilis Bates, 1878 is a junior synonym of N. nebrioides Perty, 1830, and Notiobia umbrata Bates, 1882 is a junior synonym of N. jlavicinctus Erichson, 1847. The Brazilian Notiobia species belong to at least three different species groups, each distributed from Brazil over the North-Western part of South America, Central America to Mexico.