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1.
《Journal of Natural History》2012,46(35-36):2305-2320
Recent studies indicate that populations historically called Leptodactylus fuscus (Schneider, 1799) comprise at least three well‐differentiated lineages. Herein, we describe the reproductive ecology of a southeastern clade population of L. fuscus, and review the characters of the reproductive ecology for several populations of the northern and southeastern clades. Most reproductive activity occurred in December and January, which coincided with the highest rainfall period. Males had an aggregated spatial distribution in the central area of the ponds. Three courtship interactions were observed. A female was observed closing the entrance to a burrow with moist sand after oviposition. This behaviour is described for the first time in L. fuscus. The review of the reproductive biology of the northern and southeastern clades indicates a relatively high plasticity in L. fuscus. Furthermore, the results corroborate the suggestion, based on molecular data, that the northern and southeastern clades of L. fuscus represent distinct evolutionary units.  相似文献   
2.
Habitat fragmentation strongly affects the abundance, distribution, body size and population genetics of invertebrates. Urban growth in Brazil has led to severe fragmentation, especially in the Atlantic Forest and savannas. The effects of this fragmentation on the common funnel-web spider Aglaoctenus lagotis were examined in two forest fragments within the interior savanna: a smaller fragment within an urban environment and a larger fragment within a rural environment. The reproductive period occurred in October, coinciding with the beginning of the rainy season, when the species was aggregated in the two forest fragments. The smaller fragment contained a larger population, and the spiders had a larger average prosoma size and web area. The presence of a larger population in a smaller area within the urban centre may reflect a limited dispersal ability, reduced predator abundance or low interspecific competition. The larger prosoma length and web area in the smaller habitat fragment suggest greater resource availability and a higher probability of capturing prey in the urban environment. In both areas, a larger number of capture threads was positively correlated with the presence of inquiline spiders in the webs. The genetic data indicate close similarity between and within the two areas, indicating that the species has low genetic variability or that the areas studied, consistent with their proximity, have separated only recently. Most savannas and forests in midwestern Brazil have recently undergone severe fragmentation, and further studies of this nature are needed.  相似文献   
3.
《Journal of Natural History》2012,46(32):3029-3037
The present study describes the reproductive biology of Scinax fuscomarginatus in a remnant of Cerrado in south‐eastern Brazil. Observations were made between September 2002 and March 2004 at Estação Ecológica de Itirapina, State of São Paulo, south‐eastern Brazil. Breeding activities occurred in lentic and temporary bodies of water during the rainy season. Scinax fuscomarginatus exhibited a prolonged breeding pattern and a lek mating system. Males were smaller than females and defended individual calling areas through acoustic and physical interactions. Resident males consistently won encounters, but did not differ in size or mass from intruder males. Satellite behaviour was observed, but no female or amplected pair interception was registered. Scinax fuscomarginatus exhibited low operational sex ratios and the general reproductive mode in which eggs are laid in the water and tadpoles are aquatic. Amplexus was axillary and the eggs were deposited at the bottom of temporary ponds. Details on oocytes, egg masses, and eggs are included.  相似文献   
4.
《Journal of Natural History》2012,46(7-8):491-512
Mammal abundance, richness, and community structure were examined in fragments of savannah and in gallery forests of south-western Brazil in order to assess the influence of fragment size and habitat on the communities. Five savannah fragments and two gallery forests were sampled. Within the savannah fragments, environmental parameters such as tree and shrub densities were measured. Live-traps and pitfalls were used for trapping small mammals; larger mammals were recorded from footprints and sightings. Seventeen species of small mammal and 15 species of large mammal were recorded. Small mammals were affected by fragment size and isolation, whereas larger mammals were not. Communities of small mammals were better structured in the largest fragments, and those in smaller fragments were subsets of the communities in larger fragments. Gallery forests revealed a rather different assemblage of mammals, but also contained species common to both gallery and large savannah remnants. Data are discussed relating mammal community structure to area size and vegetation structure, in an attempt to understand the present conservation status of this fragmented landscape.  相似文献   
5.
Ants commonly participate simultaneously in mutualisms with honeydew-producing hemipterans and extrafloral nectar-bearing host plants. These interactions are based on the exchange of resources (honeydew and extrafloral nectar) for ant protection against natural enemies. The benefits may vary according to the species of ant interacting, and the outcomes for the host plant and hemipteran will depend on the results of the ant-plant-hemipteran relationship as a whole. We studied a plant-mealybug association with Camponotus crassus Mayr (Formicinae) and Ectatomma tuberculatum Olivier (Ectatomminae) in a Brazilian tropical savanna. We aimed to elucidate whether the frequency of visitation by different species of ants can be affected by neighbouring colonies of mealybugs, and whether these ant species influence the number of hemipterans in a different way. Furthermore, we intended to find out whether the interaction between ant and hemipteran has any effect on the proportion of fruit production or on the abundance of trophobiont and non-trophobiont herbivores, also influenced by the ant species. Our results show that neighbouring aggregations of mealybugs influenced the frequency of ant visitation and the ants affected the number of nymphs over time, with both positive results only for C. crassus. We also detected an indirect negative effect on proportion of fruit production and an increase in abundance of trophobiont and non-trophobiont herbivores in the presence of C. crassus-mealybug interaction. Thus, we provide further evidence that colonies of hemipterans interacting with ants can be beneficial for these herbivorous insects, but they are quite harmful to the host plant. Nevertheless, the outcomes can be highly conditional in relation to ant species.  相似文献   
6.
《Journal of Natural History》2012,46(29-32):1841-1851
Phyllomedusa azurea and P. sauvagii are treefrogs from seasonal dry environments of Central Brazil. We report on reproductive and other natural history features of these species. The study was carried out in Serra da Bodoquena, Mato Grosso do Sul, Brazil. The reproductive period was determined by the presence of vocalizing males, amplectant pair or presence of tadpoles. The reproductive effort was measured as the ratio of gonad mass in relation to body mass (BM). The reproduction of both species was correlated with the rainy season. Female P. sauvagii produced more eggs and their eggs were larger than those of P. azurea. Both species showed sexual dimorphism in relation to the snout–vent length (SVL) and BM. The mating behaviour of both species was similar. Males in both species showed similar reproductive efforts, but females of P. azurea invested more in gonads compared to the males of P. sauvagii. Phyllomedusa azurea showed a significant relation between SVL versus number of the mature eggs (NME), and P. sauvagii between SVL versus NME and BM versus ovarian mass.  相似文献   
7.
The new hybosorine genus Taisia Frolov, Ocampo, Akhmetova et Vaz-de-Mello, gen. nov. is described from T. cornitermitis Frolov, Ocampo, Akhmetova et Vaz-de-Mello, sp. nov. from Mato Grosso State, Brazil. Taisia gen. nov. can be easily distinguished from the rest of the Neotropical Hybosorinae genera by the following characters: mandibular teeth long and robust; pronotum with serrate lateral margins; scutellum with two deep rectangular fossae basally; and metatibial apex protruding. Males of T. cornitermitis sp. nov. differ in having feather-like setae on the three basal tarsomeres of meso- and protarsi. The new taxon is associated with termites Cornitermes cf. bequaerti Emerson, 1952.

www.zoobank.org/urn:lsid:zoobank.org:pub:439DDABB-EBC2-4870-AA05-76ADC3BDB7D9  相似文献   

8.
9.
《Journal of Natural History》2012,46(27-28):1737-1749
ABSTRACT

Ants are abundant in terrestrial ecosystems, especially in the Brazilian Cerrado, where they can play several roles at different levels of the food chain, including protection of plants against herbivores. Although there are many studies that evaluate the ant–plant interaction in the Cerrado, little is known about the natural history of most species of ants. Camponotus crassus Mayr, 1862, for example, is considered one of the main agents of plant biotic defence in Cerrado. But there are no studies specifically focused on this species, which hinders the understanding of how arthropod–plant interactions are structured in Cerrado. Here, we describe the natural history and ecology of the foraging of the C. crassus. We conducted the study from January 2013 to December 2014 in 10 quadrants of 40 m2 to measure: the abundance, density and distribution of nests, location of the nests, the internal structure of the nests, the daily foraging of workers out of the nest, the food items they collect and the existence of territoriality and dominance of the workers on the soil and vegetation. We found 18 nests, 13 in the soil and 5 in hollow trunks on the ground with variable internal structures. The distribution of nests is aggregate, with density of 0.045 nests/m2 and average distance of 3.73 m between nests. The foraging activity occurs on the daytime during the rainy and dry season. Extrafloral nectar and honeydew were the resources most collected, comprising 83.33% of the resources in the rainy period and 30% in the dry period. Camponotus crassus is a dominant species, especially on vegetation, although it also forages on the soil. This is the first study to evaluate in detail the natural history and foraging ecology of C. crassus, a diurnal, aggressive and territorial ant that mainly forage climbing onto the plants.  相似文献   
10.
《Journal of Natural History》2012,46(19-20):1209-1246
ABSTRACT

A genus of small, yellow mimallonid moths, Zaphanta Dyar, is revised. This genus has been shown to be sister to the remainder of Mimallonidae, and therefore has been placed in its own monogeneric subfamily, Zaphantinae St Laurent and Kawahara. Long considered monotypic or bitypic, Zaphanta have not been the focus of any systematic treatment. The moths belonging to this genus are found throughout Central and South America, and detailed examination of several disparate, as well as sympatric, populations of Zaphanta have revealed numerous undescribed species all of similar appearance, but with distinct male genitalia, which we describe here. We redescribe Z. infantilis Dyar and Z. fraterna Schaus, and describe the females of both for the first time. An additional nine new species are described and figured from the Amazon, Cerrado and Atlantic Forest: Z. acuta sp. nov., Z. anas sp. nov., Z. bahiana sp. nov., Z. beckeri sp. nov., Z. elephanta sp. nov., Z. elephanticula sp. nov., Z. machaera sp. nov., Z. rawlinsi sp. nov. and Z. stiletto sp. nov. One of these, Z. beckeri, may be extremely imperilled due to deforestation.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B45DDB85-977F-42EF-9F2F-DB48827E521Ehttp://www.zoobank.org/urn:lsid:zoobank.org:act:C6F7DBF4-4871-403D-A387-DD920BA76D8Bhttp://www.zoobank.org/urn:lsid:zoobank.org:act:C4C8DAAF-8C60-4C16-A626-3641EA3817FBhttp://www.zoobank.org/urn:lsid:zoobank.org:act:6A57E1CC-D3E5-4E45-8C82-7006295ADF1Fhttp://www.zoobank.org/urn:lsid:zoobank.org:act:03241157-1925-4EF6-B426-A8E816C7E457http://www.zoobank.org/urn:lsid:zoobank.org:act:A00749E5-888C-45FB-8FAA-0302A402496Fhttp://www.zoobank.org/urn:lsid:zoobank.org:act:89132977-91DC-4424-9C0E-98A954E467CAhttp://www.zoobank.org/urn:lsid:zoobank.org:act:11AA3541-C7A4-4292-A5CA-10B89C5FAD2Chttp://www.zoobank.org/urn:lsid:zoobank.org:act:A5FA3ED1-5994-46B4-B018-1FA055C76496http://www.zoobank.org/urn:lsid:zoobank.org:act:F1C63621-EF30-40B1-B437-87A79BD7E339  相似文献   
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