4 resultados para região Neotropical.
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Populations of Synchaeta jollyae (Shiel & Koste, 1993) (Rotifera), a species recently recorded for the first time in Brazil and South America, were analyzed in reservoirs in Southeast Brazil. Sampling was carried out monthly from August 2006 to July 2007 at Furnas Reservoir in the Rio Grande basin, state of Minas Gerais, and in four cascade reservoirs in the Tiete River basin (Barra Bonita, Bariri, Ibitinga and Nova Avanhandava) state of Sao Paulo, in June and September 2008 and in January and May 2009. Synchaeta jollyae occurred in most samples and periods. From the results obtained it is evident that S. jollyae occurs in water bodies of varied trophic status but reaches larger populations in eutrophic water bodies and during lower temperature periods. The greatest densities of S. jollyae were found in the eutrophic Bariri Reservoir, on the Tiete River, during the winter. Mann-Whitney test confirmed the significant difference between the population densities in periods of high and low temperatures, with populations reaching higher densities at lower temperatures. It is not yet possible to tell whether S. jollyae is a widely distributed species that has been overlooked in previous plankton studies in South America. Wherever these populations of S. jollyae might have originated, it appears to be a species well established and adapted to a wide range of conditions in the Neotropics.
Resumo:
Diversity of Ephemeroptera (Insecta) of the Serra da Mantiqueira and Serra do Mar, southeastern Brazil. The aim of this study was to inventory the mayfly fauna, based on nymphal and alate stages, in Serra da Mantiqueira and in Serra do Mar, Sao Paulo State, as well as to present information about habitats used by the genera. Nymphs were collected in several streams and mesohabitats with a Surber sampler and the winged stages with light attraction methods, entomological nets, and Malaise traps. In all, eight families and 33 genera were recorded, representing a very significant portion of the Brazilian fauna (80% of families and 49% of genera). Furthermore, it was possible to identify 11 species, of which two are new records for the state: Tricorythodes santarita Traver and Caenis reissi Malzacher. Despite the high diversity recorded, the accumulation curves presented an ascending form, indicating an increase in the number of genera with additional sampling effort. The high richness found in these areas are in agreement with the high biodiversity of the Atlantic Forest biome and the sampling effort employed, which included the use of different methods, the collection of both nymphs and winged stages, and the sampling of a large area with diverse streams and habitats.
Resumo:
Entering behavior of Gasteruption brachychaetum Schrottky (Hymenoptera, Gasteruptiidae) into a nest of Hylaeus Fabricius (Hymenoptera, Colletidae). Nests of Hylaeus aff. guaraniticus (Schrottky, 1906) were parasited by females of Gasteruption brachychaetum Schrottky, 1906 in trap nests in Sao Paulo(Brazil). This is the first host record of a Gasteruptiidae in the Neotropical Region. The behavior of a G. brachychaetum female entering a host's nest is described as follows: an inquiline female hovered near the host's nest, landed and detected that a female of H. aff. guaraniticus was inside the nest, waited for the host female to fly out, entered backwards into the nest, remained there for almost six minutes, and then went out the nest. The development time of immature stages of G. brachychaetum varied between 16 and 299 days.
Resumo:
Dentre os organismos que atuam no controle biológico natural dos tefritídeos, os representantes da família Braconidae constituem-se no mecanismo de parasitismo natural mais atuante, e na região Neotropical, representantes de Opiinae são os principais agentes de controle de Anastrepha. Este trabalho teve por objetivo conhecer a percentagem de parasitismo e as espécies de braconídeos associados às fruteiras cultivadas em municípios da região Litoral Sul da Bahia. No período de agosto de 2005 a março de 2008, coletaram-se frutos hospedeiros de moscas-das-frutas de diversas espécies botânicas, e dos frutos foram obtidas as seguintes espécies de Anastrepha: A. fraterculus, A. obliqua, A. bahiensis, A serpentina, A. sororcula e A. zenildae. Do total de 838 exemplares de braconídeos, 21,36% foram da espécie Utetes anastrephae (Viereck), provenientes de cajá, carambola, goiaba, manga e pitanga; 4,42% da espécie Asobara anastrephae (Muesebeck) obtidos dos frutos de cajá, carambola e goiaba, e apenas um exemplar da espécie Opius bellus Gahan (0,12%) que emergiu da amostra de goiaba. A espécie Doryctobracon areolatus (Szépligeti) (74,10%) foi predominante e emergiu dos pupários provenientes de todos os frutos hospedeiros coletados, provavelmente pela maior eficiência desta espécie em localizar as larvas dos tefritídeos. A percentagem média de parasitismo de Anastrepha spp. foi de 4,45%.