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1.
Nests of Schneider’s dwarf caiman, Paleosuchus trigonatus, were located in the forests around three streams that drain into the Xingu River, Brazilian Amazonia, in October 2014. Camera traps were installed at the edge of four nests to document predators and female parental care. At two nests, females unsuccessfully defended their nests against one or more giant armadillos, Priodontes maximus, and nine-banded armadillos, Dasypus novemcinctus. Both armadillo species responded to the attack by fleeing and returning on the opposite side of the nest by going around the tree under which the nest was located. Giant armadillos have never before been recorded consuming caiman eggs and their diet has been described as consisting mostly of ants and termites. Another species of armadillo, Cabassous unicinctus, was also registered digging into a nest and probably consuming eggs, though it is generally considered to be primarily insectivorous. A tayra (Eira barbara), lizard (Tupinambis teguixin) and coati (Nasua nasua) were also registered taking eggs from nests during the day, but we obtained no registers of nest defence by caimans during the day. The three nests were attacked after 60 days of incubation, when the eggs were well developed.  相似文献   

2.
The green June beetle (Cotinis nitida) was observed in northern Virginia for a second and third flight season. The study yielded some results that were consistent with earlier findings, namely that mate-locating beetles were vulnerable to attack by avian predators and matings occurred primarily early in the flight season. Novel findings included the following: (1) blue jays (Cyanocitta cristata) were the major predators, not common grackles (Quiscalus quiscala), (2) some jays appeared to selectively prey on female beetles, (3) competition for mates among male beetles could be so intense that some males attempted to copulate with already mated (unreceptive) females, and (4) the sex ratio of the beetle population feeding on wild blackberries remained near equality late in the flight season despite the fact that the sex ratio of the population of beetles at the emergence site became highly female-biased over time.  相似文献   

3.
《Journal of Natural History》2012,46(31-32):1921-1938
We examined the Chrysomelidae communities from representative sites of different ecosystems in Paraná State, Brazil, comparing their spatial and temporal changes. Sampling was undertaken using malaise traps at eight sites during a 2-year period. Chrysomelidae represented 19.1% of all the Coleoptera sampled, with a total of 7611 specimens and 465 species. Galerucinae was the most abundant and richest subfamily. Ponta Grossa was the most abundant site, São José dos Pinhais the richest, Fênix the poorest, Jundiaí do Sul the most uniform, and Antonina had the highest dominance of just a single species. Approximately 79% of the species were represented by fewer than 10 specimens and the 10 most abundant species represented 44.7% of all chrysomelids collected. None of the species were collected at all of the sites, but 325 were unique, reflecting the low similarity among sites. Sites with similar phytophysiognomies were more similar in terms of their Chrysomelidae species compositions. Similarities between years were slightly higher than similarities between sites.  相似文献   

4.
《Journal of Natural History》2012,46(33-34):2151-2174
The inventory of Brazil’s marine sponge fauna is notably fragmentary; knowledge remains basic even in the vicinity of some important urban areas. Accordingly, we set up a plan to prioritize taxonomic study of sensitive areas, coupling high biodiversity potential and likely outstanding human pressure on biological resources. One such area comprises the fringing urban reefs of Maceió (Alagoas State, northeastern Brazil), from where three new demosponges are described here: Plakina coerulea sp. nov., Rhabderemia meirimensis sp. nov. and Mycale rubra sp. nov. The new Rhabderemia shares with Biemna, Desmacella, Neofibularia and Sigmaxinella, the possession of distally microspined sigmas. Recent molecular results have shown these taxa to be only distantly related to chelae-bearing Poecilosclerida, hence our decision to leave the new species as ordo incertae sedis. It is proposed that the intertidal or shallow subtidal sponge fauna in northeastern Brazil’s reefs deserves enhanced conservation effort to preserve what remains in these highly impacted ecosystems. http://www.zoobank.org/urn:lsid:zoobank.org:pub:4F150A0A-2371-40A1-B7B2-8CD14CEB885C  相似文献   

5.
A study aimed at testing the contested validity of the subspecies Laudakia stellio daani yielded novel insights into the essence of subspecies. We examined morphologically museum specimens from Greece, Aegean islands, and Anatolia (n?=?118; not all could be used in all analyses). Beyond the conventional mensural, meristic and qualitative characters we quantified 14 coloration characters, thus totalling 34 characters (including sex). Biometry was statistically analysed within and between the two geographically defined presumed subspecies, L. s. daani and L. s. stellio. Excluding or including broken‐tailed specimens changed the outcome of tests. Significant minor directional asymmetry occurred in one of four character‐taxon combinations. Phenetic cluster analysis poorly separated the two presumed subspecies when all characters, including those with discordant variation, were included; after selection of characters, the separation improved. Some biometric characters distinguish the two presumed subspecies, confirming their validity. The associations of significant inter‐character correlations differed between the two subspecies. Additionally, the two differed in parameters reflecting selection pressures and social structure: L. s. stellio is more colourful than L. s. daani; its sexual dimorphism is mainly chromatic, versus mensural in L. s. daani; and its population seems to include many males with underdeveloped callous scales, presumably socially subordinate, versus very few in L. s. daani.  相似文献   

6.
《Journal of Natural History》2012,46(29-30):1767-1785
ABSTRACT

In the present study we investigated the diet of Eleonora’s falcons in Greece and assessed the regional dietary pattern of 16 breeding colonies of the Aegean. Overall 224 nests were visited and a total of 8067 prey items were collected which contained two mollusca classes, seven insect orders, one reptile family, two mammalian taxa and at least 54 avian species. Cicadas were the most common insects found in pellets (45.1%) followed by flying ants (34.8%) and beetles (15.8%) while just 20 species (33.3%) accounted for over 90% of the avian prey items identified in bird remains dominated (>50%) by the Willow Warbler (Phylloscopus trochilus), the Red-backed Shrike (Lanius collurio) and the Whitethroat (Sylvia communis). Insect feeding peaked in late August (39.8%) and late September (20.8%), whereas bird remains built up in falcon nests from mid-August onwards, culminating in late September (57.2%) and declined abruptly afterwards. Overall the falcons’ diet diversity increased as the breeding season progressed and from the north towards the south Aegean. The avian prey species richness was negatively influenced by the distance of the colonies from the mainland and the weather conditions during September which coincides with the fledgling period of the young and the autumn peak of passerine migration.  相似文献   

7.
《Journal of Natural History》2012,46(20):2425-2439
Three new species of Benthana Budde-Lund, 1908 are described from material collected near São Fancisco de Paula, a town in the north-east of the southernmost Brazilian State, Rio Grande do Sul (RS). The new species are: Benthana serrana sp. nov., Benthana trinodulata sp. nov. and Benthana araucariana sp. nov. (from Araucaria Forest). The presence of more than one nodulus lateralis on coxal plate VII, a characteristic not previously known in the genus, is reported. New occurrences of B. picta (Brand, 1833) and B. taeniata (Araujo and Buckup, 1994) are also recorded. A method is given for defining the shape of the exopod of pleopod 1 of the male based on morphometry.  相似文献   

8.
9.
Landscape modification is a key driver of global species extinction. Thus, understanding how species react to changes is essential for effective conservation management in modified landscapes. We examined the impact of selected land use patterns on the critically endangered Ceratophora tennentii in the Knuckles mountain range of Sri Lanka where lizards occupy patches of both natural undisturbed forests and modified plantations – evidently, those with a forest canopy. We tested three potential explanations for non-random habitat selection: availability of suitable microhabitat pockets, availability of prey and direct threats from humans. The microhabitat pockets occupied by the lizards were characterised by shade, humidity and the density of perches. Most lizards were found in mixed cardamom forests followed by natural forests and cardamom plantations, but none were observed in the pine plantations. Food availability showed similar patterns among habitats. Direct mortality by humans did not influence the distribution of this species. Our work indicates that habitat modifications that retain the structural complexity of the vegetation would still permit the existence of the species in densities equal to or greater than that of undisturbed forest patches. It adds to a growing body of literature that signifies the importance of disturbed habitats (intermediate disturbance hypothesis) in protecting threatened species of fauna. It is highly unlikely that some disturbed habitats will be ever be returned to their former pristine state in time frames that are important for species’ conservation. Hence, attention is needed in developing suitable approaches to manage and conserve species across disturbed habitats.  相似文献   

10.
《Journal of Natural History》2012,46(3-4):171-182
Tropidurus torquatus lizards commonly consume vegetal matter as part of their diet. However, it is not known to what extent the rate of consumption of plant material varies among populations. We investigated the consumption of plant material in 10 populations of T. torquatus in eastern Brazil. In all populations, lizards consumed plant matter (especially fruits and flowers). The proportion of plant volume in the diet varied from 2.1% to 58.0% of the total volume consumed. Differences in volumetric proportion of plant material consumed did not result from lizard body size or population latitude. The volumetric proportion of plant material did not differ between sexes at each locality; however, there was a slight trend for larger lizards to consume more plant parts. The data obtained indicate that the observed interpopulational variation in plant consumption by T. torquatus results from local environmental factors, mainly the availability of plant matter.  相似文献   

11.
《Journal of Natural History》2012,46(11-12):721-728
Although D’Orbigny’s slider (Trachemys dorbigni) is the most abundant freshwater chelonian species in southern Brazil, little is known about its feeding habits. Our goal was therefore to evaluate this species’ dietary composition and niche variation there. For this, we collected road-killed animals (n = 73) on a federal highway (BR 392) between 2002 and 2003, and analysed their gut contents. We identified 26 different dietary items, and our results indicated that D’Orbigny’s slider is omnivorous in this area. Total food volume, as well as the degree of herbivory and carnivory, were similar between males and females. However dietary composition of plants was different: although both males and females fed on underwater plant matter, only females consumed surface macrophytes. This finding suggested differential microhabitat usage between males and females throughout the swamps.  相似文献   

12.
On 29 May 1770 Joseph Banks described a spectacular swarming of ‘milions’ [sic] ‘of one sort’ of butterfly at Thirsty Sound, near what is now Rockhampton, Queensland, comparing it to a species from China that had been named by Linnaeus. Discovery of what appears to be an Endeavour voyage specimen of this Australian butterfly in the Hunterian Zoology Museum, Glasgow, allows us to confirm its long-suspected identity as Tirumala hamata hamata (Macleay) – a species unnamed and unknown at the time of Cook’s first voyage. Investigations into several collections that include eighteenth-century Australian Lepidoptera and associated literature have not positively identified any further specimens taken from the swarm, although a pair in the Oxford University Museum of Natural History could be from the same source. Taxonomic confusion due to mimicry, convergence and/or non-divergence affecting blue tiger patterned butterflies is most likely the principal reason such a specimen has previously gone undetected.  相似文献   

13.
《Journal of Natural History》2012,46(31):2913-2933
Members of two hunting‐wasp families, Pompilidae and Sphecidae, are among the major predators of orb‐web spiders. In this study, we collected paralysed spiders from natural nests and trap‐nests provisioned by sphecids in an area of Brazilian Atlantic Forest, and compared these data with the composition of species collected by visual searching during one year. Prey preferences were analysed based on the relative abundance of spider species, their size and web characteristics. We also compiled a list of orb‐weavers captured by four sphecid genera reported in 40 other studies. A large number of prey was obtained from natural nests of Trypoxylon (Trypargilum) albonigrum in Parque Estadual Intervales, especially species of Eustala, Parawixia, and Araneus (Araneidae). Other prey, stored in trap‐nests by T. lactitarse and unidentified hunting‐wasp species, included Nephila (Tetragnathidae), Parawixia, Ocrepeira, Mecynogea, Acacesia (Araneidae), and other spider species that were less abundant. All the species that were heavily preyed upon had a relatively lower abundance in our samples of prey availability. The range of body sizes of spiders captured by Trypoxylon in our study area include the size of some abundant orb‐weavers always absent in their nests. These results indicate that factors other than abundance in the field and the spider's size influence prey selection or susceptibility to attack.  相似文献   

14.
Ephippia of Cladocera (Crustacea: Branchiopoda) are found in the Oligocene deposits of Tremembé Formation (Taubaté Basin, Southeast Brazil). Thirty specimens from a short stratigraphic interval of a 115-m section of a core drilled in Taubaté city, São Paulo state, have been studied. Based on the morphology, we assumed that they might belong to two diferent species of Daphnia (Ctenodaphnia) which lived either in the Tremembé palaeolake or in some surrounding temporary waters. Our find represents the oldest record of fossil ephippia in South America and the second record of Daphnia (Ctenodaphnia) in the former Gondwana. A tentative palaeolimnological interpretation is proposed based on the ephippia occurrences, allied to ostracod and lithological data.  相似文献   

15.
16.
We use a panbiogeographical approach to determine the distribution pattern of dung beetles from a border region between Cerrado and Rondônia biogeographical provinces in Brazil. We constructed 54 individual tracks and 12 generalized tracks. The generalized tracks infer historical events that have happened in the past, highlighting the significant role of vicariant processes and their influence on the current distribution pattern of dung beetles from the Pantanal–Cerrado Border. The study region is a biogeographical node, including representatives from different biogeographic origins. Contrary to previous suggestions, the Scarabaeinae fauna of southern Rondônia province is not related to Amazonian fauna. Rather, it shows stronger connections with Chaco. Hence we suggest the inclusion of the southern part of the province of Rondônia, representing the Pantanal depression itself, as a new biogeographical district within Chaco province.  相似文献   

17.
18.
《Journal of Natural History》2012,46(21-22):1291-1304
We examined the influence of weather factors, including temperature, humidity and sunlight, on the diurnal flight activity of Ichneumonidae (Insecta, Hymenoptera) in an oak wood in Cabañeros National Park (Spain) in June, when the annual flight activity reaches its maximum. Ichneumonidae flight activity peaked at temperatures of around 25.6–27°C, which is reached in late morning to midday and in the evening (20.00–21.00 h). The evening peak in activity was greater. Males were more active in the morning, whereas females were more active in the afternoon. Relative humidity is closely related to air temperature but showed little correspondence with flight activity. Illuminance did not explain diurnal flight activity, other than dictating diurnal or nocturnal habits of Ichneumonidae.  相似文献   

19.
《Journal of Natural History》2012,46(7-8):465-479
This study compares the diets of the giant otter and the Neotropical otter, two Lutrinae species which feed mainly on fish. The study was carried out through the analyses of faecal samples collected between 2006 and 2008 (82 giant otter and 75 Neotropical otter) in the Jaú National Park. The giant otter feeds mainly on Cichlidae, Erythrinidae and Characidae, while the Neotropical otter consumes Doradidae, Loricariidae and Cichlidae. The two otter species had low diet similarity (Pianka’s Index = 0.16). The giant otter consumed larger fish than the Neotropical otter, which probably explores shallow river parts in search of small catfish. Prey other than fish were more frequent in the diet of the Neotropical otter, whereas giant otters ate a greater diversity of fish families. Increasing knowledge of the feeding habits and interactions of these two top-order predators is vital to determine appropriate protection and management policies.  相似文献   

20.
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