Efficiency of uniparental male and female care against egg predators in two closely related syntopic harvestmen

Although the benefits of maternal care have been investigated in many species, the caring role of males in species with exclusive paternal care has received less attention. We experimentally quantified the protective role of paternal care in the harvestman Iporangaia pustulosa. Additionally, we compared the effectiveness of paternal care against predation in this species with a syntopic harvestman with maternal care, Acutisoma proximum. We demonstrated that nearly one-third of the unprotected Iporangaia clutches disappeared entirely in 12 days, while the other two-thirds suffered a mean reduction of 55% in egg number. Conversely, 50% of the control clutches did not suffer any reduction, and only one was entirely consumed by predators. We also demonstrated that the mucus coat that covers Iporangaia clutches has an important deterrent role against predation by conspecifics: 58.3% of the clutches without mucus were attacked and three of them were entirely consumed, whereas only three clutches with mucus were attacked, suffering a reduction of up to three eggs. Iporangaia males were as efficient as Acutisoma females in protecting eggs. However, unattended Acutisoma eggs were attacked 20% more frequently than unattended Iporangaia eggs. Unattended Iporangaia eggs are protected by a mucus coat that prevents or decreases predation rate, whereas Acutisoma eggs are more susceptible to predation, probably because they lack this mucus coat. Thus, besides the fact that Iporangaia males efficiently protect the offspring against egg predators, females also contribute to egg protection by providing a mucus coat that deters egg predators. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Ecological niche modeling and principal component analysis of Krameria Loefl. (Krameriaceae)

Krameria plants are found in arid regions of the Americas and present a floral system that attracts oil-collecting bees. Niche modeling and multivariate tools were applied to examine ecological and geographical aspects of the 18 species of this genus, using occurrence data obtained from herbaria and literature. Niche modeling showed the potential areas of occurrence for each species and the analysis of climatic variables suggested that North American species occur mostly in deserted or xeric ecoregions with monthly precipitation below 140 mm and large temperature ranges. South American species are mainly found in deserted ecoregions and subtropical savannas where monthly precipitation often exceeds 150 mm and temperature ranges are smaller. Principal Component Analysis (PCA) performed with values of temperature and precipitation showed that the distribution limits of Krameria species are primarily associated with maximum and minimum temperatures. Modeling of Krameria species proved to be a useful tool for analyzing the influence of the ecological niche variables in the geographical distribution of species, providing new information to guide future investigations. (C) 2011 Elsevier Ltd. All rights reserved.

Local richness and distribution of the lizard fauna in natural habitat mosaics of the Brazilian Cerrado

We investigate local lizard richness and distribution in central Brazilian Cerrado, harbouring one of the least studied herpetofaunas in the Neotropical region. Our results are based on standardized samplings at 10 localities, involving 2917 captures of 57 lizard species in 10 families. Local richness values exceeded most presented in earlier studies and varied from 13 to 28 species, with modal values between 19 and 28 species. Most of the Cerrado lizard fauna is composed of habitat-specialists with patchy distributions in the mosaic of grasslands, savannas and forests, resulting in habitat-structured lizard assemblages. Faunal overlap between open and forested habitats is limited, and forested and open areas may act as mutual barriers to lizard distribution. Habitat use is influenced by niche conservatism in deep lineages, with iguanians and gekkotans showing higher use of forested habitats, whereas autarchoglossans are richer and more abundant in open habitats. Contrary to trends observed in Cerrado birds and large mammals, lizard richness is significantly higher in open, interfluvial habitats that dominate the Cerrado landscape. Between-localities variation in lizard richness seems tied to geographical distance, landscape history and phylogenetic constraints, factors operating in other well-studied lizard faunas in open environments. Higher richness in dominant, open interfluvial habitats may be recurrent in Squamata and other small-bodied vertebrates, posing a threat to conservation as these habitats are most vulnerable to the fast, widespread and ongoing process of habitat destruction in central Brazil.

Feeding habits of the maned wolf, Chrysocyon brachyurus (Carnivora: Canidae), in southeast Brazil

The feeding habits of the maned wolf were studied in southeast Brazil to understand its response towards changes in the environment and in relation to its prey. By occurrence, miscellaneous fruits, small mammals and wolf`s fruit were the most consumed items. Armadillos, small mammals and wolf`s fruit ( Solanum lycocarpum) provided most of the ingested biomass. While wolf`s fruit and small mammals were mainly consumed in the dry season, other miscellaneous fruits were taken mostly in the wet season. There was selectivity in the predation on some small mammal species. The maned wolf`s diet followed patterns similar to those found in more pristine areas.

Fragmentation drives tropical forest fragments to early successional states: A modelling study for Brazilian Atlantic forests

Land use leads to massive habitat destruction and fragmentation in tropical forests. Despite its global dimensions the effects of fragmentation on ecosystem dynamics are not well understood due to the complexity of the problem. We present a simulation analysis performed by the individual-based model FORMIND. The model was applied to the Brazilian Atlantic Forest, one of the world`s biodiversity hot spots, at the Plateau of Sao Paulo. This study investigates the long-term effects of fragmentation processes on structure and dynamics of different sized remnant tropical forest fragments (1-100 ha) at community and plant functional type (PFT) level. We disentangle the interplay of single effects of different key fragmentation processes (edge mortality, increased mortality of large trees, local seed loss and external seed rain) using simulation experiments in a full factorial design. Our analysis reveals that particularly small forest fragments below 25 ha suffer substantial structural changes, biomass and biodiversity loss in the long term. At community level biomass is reduced up to 60%. Two thirds of the mid- and late-successional species groups, especially shade-tolerant (late successional climax) species groups are prone of extinction in small fragments. The shade-tolerant species groups were most strongly affected; its tree number was reduced more than 60% mainly by increased edge mortality. This process proved to be the most powerful of those investigated, explaining alone more than 80% of the changes observed for this group. External seed rain was able to compensate approximately 30% of the observed fragmentation effects for shade-tolerant species. Our results suggest that tropical forest fragments will suffer strong structural changes in the long term, leading to tree species impoverishment. They may reach a new equilibrium with a substantially reduced subset of the initial species pool, and are driven towards an earlier successional state. The natural regeneration potential of a landscape scattered with forest fragments appears to be limited, as external seed rain is not able to fully compensate for the observed fragmentation-induced changes. Our findings suggest basic recommendations for the management of fragmented tropical forest landscapes. (C) 2011 Elsevier B.V. All rights reserved.

Energy substrate utilization during nightly vocal activity in three species of Scinax (Anura/Hylidae)

Anuran amphibians exhibit different patterns of energy substrate utilization that correlate with the intensity of vocal and locomotor activities. Given the remarkable differences among species in breeding and feeding strategies, and the different ways energy is used in the whole animal, the suggested correlations between calling and locomotor behavior and the level of energy substrates in the muscles responsible for such activities are more complex than previously reported. We explored the relationships between calling and locomotor behavior and energy supply to trunk and hindlimb muscles, respectively, within the ecologically diverse tree-frog genus Scinax. Specifically, we measured the relative amount of carbohydrates and lipids in these two groups of muscles, and in the liver of three species of Scinax that differ in vocal and locomotor performance, and compared our results with those of two other species for which comparable data are available. We also compared the contents of lipids and carbohydrates of conspecific males collected at the beginning and after 4 h of calling activity. The stomach content to potential feeding opportunities across species was also assessed in both groups of males. Scinax hiemalis and S. rizibilis exhibit comparatively low and episodic calling during long periods of activity whereas S. crospedospilus calls at higher rates over shorter periods. Male S. hiemalis had highest levels of trunk muscle glycogen followed by those of S. rizilbilis and S. crospedospilus, respectively. There was no correlation between total lipid content in trunk muscle and calling rate among different species, suggesting that other metabolic aspects may be responsible for the energetic support for vocal activity. The levels of lipids and carbohydrates in trunk and hindlimb muscles and liver of males collected at the beginning and 4 h into the calling period were similar across species, so the extent of energetic reserves does not appear to constrain vocal or locomotor activity. Finally, we found exceptionally high levels of carbohydrates and lipids in the liver of S. rizibilis, a trait perhaps related to a long and demanding breeding period.

Non-homologous sex chromosomes in two species of the genus Eigenmannia (Teleostei : Gymnotiformes)

The Neotropical genus Eigenmannia is a fish group with unknown species diversity where representatives possess a broad range of chromosomal sex determining systems namely XY/XX, X1X2Y/X1X1X2X2, ZZ/ZW as well as homomorphic sex chromosomes. To test the homology of two heteromorphic XY sex chromosome systems present in two sympatric populations, reciprocal cross-species FISH experiments were performed using probes derived by microdissection of X and Y chromosomes present in analyzed specimens of Eigenmannia virescens and Eigenmannia sp.2, respectively. While X and Y paint probes hybridized to species-specific sex chromosomes, in reciprocal cross-FISH both probes hybridized exclusively to autosomes. The result suggests multiple independent origins of the XY systems in the analyzed populations. Copyright (C) 2008 S. Karger AG, Basel.

Isolation and characterization of microsatellite loci for white-lipped peccaries (Tayassu pecari) and cross-amplification in collared peccaries (Pecari tajacu)

White-lipped peccaries, Tayassu pecari, are neotropical ungulates whose populations have been declining in numerous locations within their geographical distribution. Here we describe 16 microsatellite loci isolated from T. pecari and their cross-amplification in collared peccaries, Pecari tajacu. In 30 individuals of T. pecari, a total of 32 alleles were found in ten polymorphic loci, ranging from 2 to 8 alleles per locus with a mean of 3.2. The expected and observed heterozygosity ranged from 0.143 to 0.802 and from 0 to 0.704, respectively. Two loci deviated from Hardy-Weinberg equilibrium. In P. tajacu, nine loci were polymorphic with a mean of 3.2 alleles per locus. These molecular markers will be useful to study the genetic status of peccary populations and, consequently, to help their conservation.

Comparative Cytogenetics and Molecular Phylogeography in the Group Astyanax altiparanae - Astyanax aff. bimaculatus (Teleostei, Characidae)

The genus Astyanax comprises small characin fish of the neotropical region. The so-called `yellow-tailed characins` compose one of the most widely distributed Astyanax groups. A. altiparanae and A. aff. bimaculatus, are evolutionarily closely related and commonly found in several Brazilian hydrographic basins. In the present work, chromosomal data of specimens of A. altiparanae and A. aff. bimaculatus from 4 hydrographic basins in the states of Sao Paulo (Upper Tiete, Paranapanema, Ribeira de Iguape) and Rio de Janeiro (Guapimirim) are shown. All the populations showed 50 chromosomes, with different karyotypic formula. Although only a single Ag-NOR bearing chromosome pair was observed, all populations possess multiple cistrons of 18S rDNA. FISH with the 5S rDNA probe showed single signals at the interstitial position of one metacentric chromosome pair. C-bands are distributed in the terminal and interstitial regions of several chromosomes. However, the As-51 satDNA are frugally located in a few chromosomes of fishes from Upper Tiete, Paranapanema and Guapimirim Rivers, being absent in individuals of A. aff. bimaculatus from Ribeira de Iguape River basin. Beside these 4 populations, molecular phylogeography studies were also performed in individuals from Middle and Lower Tiete River basin and from 2 additional collection sites in the Paranapanema and Ribeira de Iguape River basins. The phylogeographic analysis using 2 mtDNA regions (totalizing 1.314 bp of ND2 and ATPase6/8 genes) of 8 populations of the group of `yellow-tailed characins` from 3 major hydrographic basins showed structuring of populations, suggesting a correlation between chromosomal (nuclear) and molecular (mitochondrial) data. Copyright (C) 2011 S. Karger AG, Basel

Coalescent analysis of mtDNA indicates Pleistocene divergence among three species of howler monkey (Alouatta spp.) and population subdivision within the Atlantic Coastal Forest species, A. guariba

We have used coalescent analysis of mtDNA cytochrome b (cyt b) sequences to estimate times of divergence of three species of Alouatta-A. caraya, A. belzebul, and A. guariba-which are in close geographic proximity. A. caraya is inferred to have diverged from the A. guariba/A. belzebul clade approximately 3.83 million years ago (MYA), with the later pair diverging approximately 1.55 MYA. These dates are much more recent than previous dates based on molecular-clock methods. In addition, analyses of new sequences from the Atlantic Coastal Forest species A. guariba indicate the presence of two distinct haplogroups corresponding to northern and southern populations with both haplogroups occurring in sympatry within Sao Paulo state. The time of divergence of these two haplogroups is estimated to be 1.2 MYA and so follows quite closely after the divergence of A. guariba and A. belzebul. These more recent dates point to the importance of Pleistocene environmental events as important factors in the diversification of A. belzebul and A. guariba. We discuss the diversification of the three Alouatta species in the context of recent models of climatic change and with regard to recent molecular phylogeographic analyses of other animal groups distributed in Brazil.

Comparative Genetic Diversity of Wild and Captive Populations of the Bare-Faced Curassow (Crax fasciolata) Based on Cross-Species Microsatellite Markers: Implications for Conservation and Management

The bare-faced curassow (Crax fasciolata) is a large Neotropical bird that suffers anthropogenic pressure across much of its range. A captive population is maintained for conservation management, although there has been no genetic screening of stocks. Based on the six microsatellite markers developed for Crax globulosa, the genetic variability of C. fasciolata and possible differences between a wild and a captive population were investigated. Only three loci were polymorphic, with a total of 27 alleles. More than half of these alleles were private to the wild (n = 8) or captive (n = 7) populations. Significant deviations from Hardy-Weinberg equilibrium were restricted to the captive population. Despite the number of private alleles, genetic drift has probably promoted differentiation between populations. Our results indicate that wild C. fasciolata populations are genetically impoverished and structured, but species-specific microsatellite markers will be necessary for a more reliable assessment of the species` genetic diversity.

Diet and food selection by small mammals in an old-growth Atlantic forest of south-eastern Brazil

Here we describe the stomach contents of nine small mammal species (seven rodents and two didelphid marsupials) co-occurring in an old-growth Atlantic forest area. For four terrestrial rodents, we also compared the importance of arthropods in the diet and the selection of arthropod groups by comparing consumption with availability. Small mammals and arthropods were sampled in a 36-ha grid containing 25 sampling stations spaced every 150 m, and 47 stomach contents were analysed. While plant matter was the predominant item in the stomach contents of two rodents (Oligoryzomys nigripes and Rhipidomys mastacalis), four species presented arthropods as the main food item (the rodents Brucepattersonius soricinus and Oxymycterus dasytrichus, and the marsupials Monodelphis n. sp. and Marmosops incanus) and three consumed more plant matter than arthropods, but had significant amounts of both items (the rodents Delomys sublineatus, Euryoryzomys russatus and Thaptomys nigrita). Our results suggest that differences in diet, coupled with differences in habit and microhabitat preferences, are important factors allowing resource partition among species of the diverse group of co-occurring terrestrial small mammals in Atlantic forest areas. Moreover, arthropods were not preyed opportunistically by any of the four terrestrial rodents, since consumption was not proportional to availability. Rather, selection or rejection of arthropod groups seems to be determined by aspects other than availability, such as nutritional value, easiness of capture and handling or palatability.

Variety matters: adaptive genetic diversity and parasite load in two mouse opossums from the Brazilian Atlantic forest

The adaptive potential of a species to a changing environment and in disease defence is primarily based on genetic variation. Immune genes, such as genes of the major histocompatibility complex (MHC), may thereby be of particular importance. In marsupials, however, there is very little knowledge about natural levels and functional importance of MHC polymorphism, despite their key role in the mammalian evolution. In a previous study, we discovered remarkable differences in the MHC class II diversity between two species of mouse opossums (Gracilinanus microtarsus, Marmosops incanus) from the Brazilian Atlantic forest, which is one of the most endangered hotspots for biodiversity conservation. Since the main forces in generating MHC diversity are assumed to be pathogens, we investigated in this study gastrointestinal parasite burden and functional associations between the individual MHC constitution and parasite load. We tested two contrasting scenarios, which might explain differences in MHC diversity between species. We predicted that a species with low MHC diversity would either be under relaxed selection pressure by low parasite diversity (`Evolutionary equilibrium` scenario), or there was a recent loss in MHC diversity leading to a lack of resistance alleles and increased parasite burden (`Unbalanced situation` scenario). In both species it became apparent that the MHC class II is functionally important in defence against gastrointestinal helminths, which was shown here for the first time in marsupials. On the population level, parasite diversity did not markedly differ between the two host species. However, we did observe considerable differences in the individual parasite load (parasite prevalence and infection intensity): while M. incanus revealed low MHC DAB diversity and high parasite load, G. microtarsus showed a tenfold higher population wide MHC DAB diversity and lower parasite burden. These results support the second scenario of an unbalanced situation.

Canga renatae, a new genus and species of Cyphophthalmi from Brazilian Amazon caves (Opiliones: Neogoveidae)

A new genus and species of Cyphophthalmi, Canga renatae gen. nov., sp. nov., is described in the family Neogoveidae from a system of caves in the Serra de Carajas, Para State, Brazil. Canga can be easily distinguished from other neogoveid genera by the presence of a dentate claw on leg I, a unique character among known cyphophthalmid species, and by the free coxa II, which is fused to coxae III and IV in all the other neogoveid species except for the North American Metasiro. The new genus also differs from other Neotropical neogoveids in the lack of a dorsal crest on the chelicerae and in the lack of opisthosomal glands. The finding of a neogoveid in the Para State greatly increases the known distribution of South American cyphophtalmids into the Eastern Brazilian Amazon forest.

Review of the Brazilian harvestman genus Roeweria Mello-Leitao, 1923 (Opiliones: Gonyleptidae)

The genus Roeweria Mello-Leitao, 1923 is revised and a variation on external morphological characters and male genitalia is presented for Roeweria virescens (Mello-Leitao, 1923). The monotypic genus Harpachylus Roewer, 1943 is a junior synonym of Roeweria Mello-Leitao, 1923 because its type-species, H. tibialis Roewer, 1943 is a junior synonym of the type-species Roeweria bittencourti Mello-Leitao, 1923. Roeweria garrincha sp. n. from Cananeia, Sao Paulo, Brazil, is described and can be distinguished from other members of the genus by the presence of a ventral process on the penis and by very large ventral apophyses on the apex of the male femur and patella IV.