11 resultados para newly recorded species

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


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In studies carried out off the north-eastern and south-eastern coast of Brazil, three species of Prosphaerosyllis were found: P. isabellae, which was already recorded for Brazilian waters; P. xarifae, a newly recorded species for the area; and P. brachycephala sp. nov., a new to science species. Prosphaerosyllis brachycephala sp. nov., is characterized by having swollen anterior part of the body, prostomium retractable within the peristomium and anterior segments, short antennae, short peristomial and dorsal cirri, and falcigers with short, unidentate blades throughout. All these species are herein described and compared to the most similar congeners.

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A cladistic analysis using parsimony under equal weights is applied to test the phylogenetic relationships of Itatiaya Mello-Leitao, previously described in Ctenidae. The data matrix comprised 25 taxa scored for a total of 47 characters. The cladistic analysis yielded two equally parsimonious trees of 124 steps. The consensus of the two most parsimonious trees is used to discuss the phylogenetic relationships and justify taxonomic modifications. The results indicate that this genus is a representative of Zoropsidae, which is newly recorded from the Neotropical region. The monophyly of Itatiaya is supported by three non-ambiguous synapomorphies and three homoplastic synapomorphies. A new diagnosis is provided for Itatiaya. Itatiaya pucupucu is placed as sister species to the remaining species of the genus. A polytomic clade composed of Itatiaya modesta, Itatiaya iuba, Itatiaya apipema and the clade formed by Itatiaya tacamby + Itatiaya pykyyra is supported by the presence of modified cylindrical gland spigots. Additionally, the male of I. pykyyra Polotow & Brescovit is described for the first time.

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It is known that large fragment sizes and high connectivity levels are key components for maintaining species in fragments; however, their relative effects are poorly understood, especially in tropical areas. In order to test these effects, we built models for explaining understory birds occurrence in a fragmented Atlantic Rain Forest landscape with intermediate habitat cover (3%). Data from over 9000 mist-net hours from 17 fragments differing in size (2-175 ha) and connectivity (considering corridor linkages and distance to nearby fragments) were ranked under a model selection approach. A total 1293 individuals of 62 species were recorded. Species richness, abundance and compositional variation were mainly affected by connectivity indices that consider the capacity of species to use corridors and/or to cross short distances up to 30 m through the matrix. Bird functional groups were differently affected by area and connectivity: while terrestrial insectivores, omnivores and frugivores were affected by both area and connectivity, the other groups (understory insectivores, nectarivores, and others) were affected only by connectivity. In the studied landscape, well connected fragments can sustain an elevated number of species and individuals. Connectivity gives the opportunity for individuals to use multiple fragments, reducing the influence of fragment size. While preserving large fragments is a conservation target worldwide and should continue to be, our results indicated that connectivity between fragments can enhance the area functionally connected and is beneficial to all functional groups and therefore should be a conservation priority. (C) 2008 Elsevier Ltd. All rights reserved.

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Goniosomatine harvestmen have strongly armed pedipalps, generally large bodies and, commonly, very long legs (sometimes more than 20 cm), and are distributed in the Brazilian Atlantic forest, from southern Bahia to Santa Catarina. Since they are conspicuous animals and individuals of some species tend to concentrate in caves (and also under rock boulders), they have been (and still are) the target of several studies, especially those focusing on reproductive and defensive behavior, population ecology, physiology, chromosomes, etc. In spite of their importance for biological studies (some species constitute important and frequently used models for these studies), the taxonomy of Goniosomatinae has faced some problems, including misidentification, a large number of undescribed species and the lack of a phylogenetic hypothesis for the relationships among its species (which would allow evolutionary studies to be made). The last taxonomic changes in the subfamily were made 60 years ago. Considering a taxonomic revision and cladistic analysis of the subfamily to be of paramount importance, the main scope of the present paper is to provide a cladistic analysis and taxonomic revision of the species of Goniosomatinae and a new arrangement of genera (and species). The main taxonomic changes are given as follows. Six genera are recognised within the subfamily: Goniosoma; the newly described genus Pyatan; the reestablished genera Serracutisoma, Heteromitobates and Mitogoniella; and Acutisoma. New generic synonyms include: Glyptogoniosoma = Goniosomella = Lyogoniosoma = Metalyogoniosoma = Xulapona = Goniosoma, Acutisomelloides = Pygosomoides = Spelaeosoma = Serracutisoma; and Acutisomella = Heteromitobates. Newly described species include: Goniosoma capixaba; G. apoain; Pyatan insperatum DaSilva, Stefanini-Jim & Gnaspini; Serracutisoma pseudovarium; S. fritzmuelleri; S. guaricana; Heteromitobates anarchus; H. harlequin; H. alienus; Mitogoniella taquara; M. unicornis; and Acutisoma coriaceum. New combinations include: Goniosoma macracanthum (Mello-Leitao, 1922); G. unicolor (Mello-Leitao, 1932); G. carum (Mello-Leitao, 1936); Serracutisoma proximum (Mello-Leitao, 1922); S. banhadoae (Soares & Soares, 1947); S. molle (Mello-Leitao, 1933); S. thalassinum (Simon, 1879); S. catarina (Machado, Pinto-da-Rocha & Ramires, 2002); S. inerme (Mello-Leitao, 1927); S. spelaeum (MelloLeitao, 1933); Heteromitobates inscriptus (Mello-Leitao, 1922); H. albiscriptus (Mello-Leitao, 1932); Mitogoniella modesta (Perty, 1833); and M. badia (Koch, 1839). Reestablished combinations include: Mitogoniella indistincta MelloLeitao, 1936 and Acutisoma longipes Roewer, 1913. New speci. c synonyms include: Acutisomella cryptoleuca = Acutisomella intermedia = Goniosoma junceum = Goniosoma patruele = Goniosoma xanthophthalmum = Metalyogoniosoma unum = Goniosoma varium, Goniosoma geniculatum = Goniosoma venustum; Goniosomella perlata = Progoniosoma minense = Goniosoma vatrax, Glyptogoniosoma perditum = Progoniosoma cruciferum = Progoniosoma tijuca = Goniosoma dentipes; Leitaoius iguapensis = Leitaoius viridifrons = Serracutisoma proximum; Acutisoma marumbicola = Acutisoma patens = Serracutisoma thalassinum; Progoniosoma tetrasetae = Serracutisoma inerme; and Acutisoma monticola = Leitaoius nitidissimus = Leitaoius xanthomus = Mitogoniella mutila = Acutisoma longipes. The following species are considered species inquirenda: Goniosoma lepidum Gervais, 1844; G. monacanthum Gervais, 1844; G. obscurum Perty, 1833; G. versicolor Perty, 1833; and Mitogoniella badia (Koch, 1839). The monotpic genus Goniosomoides Mello-Leitao, 1932 (and its species, G. viridans Mello-Leitao, 1932) is removed from Goniosomatinae and considered incertae sedis.

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Activities involving fauna monitoring are usually limited by the lack of resources; therefore, the choice of a proper and efficient methodology is fundamental to maximize the cost-benefit ratio. Both direct and indirect methods can be used to survey mammals, but the latter are preferred due to the difficulty to come in sight of and/or to capture the individuals, besides being cheaper. We compared the performance of two methods to survey medium and large-sized mammal: track plot recording and camera trapping, and their costs were assessed. At Jatai Ecological Station (S21 degrees 31`15 ``- W47 degrees 34`42 ``-Brazil) we installed ten camera traps along a dirt road directly in front of ten track plots, and monitored them for 10 days. We cleaned the plots, adjusted the cameras, and noted down the recorded species daily. Records taken by both methods showed they sample the local richness in different ways (Wilcoxon, T=231; p;;0.01). The track plot method performed better on registering individuals whereas camera trapping provided records which permitted more accurate species identification. The type of infra-red sensor camera used showed a strong bias towards individual body mass (R(2)=0.70; p=0.017), and the variable expenses of this method in a 10-day survey were estimated about 2.04 times higher compared to track plot method; however, in a long run camera trapping becomes cheaper than track plot recording. Concluding, track plot recording is good enough for quick surveys under a limited budget, and camera trapping is best for precise species identification and the investigation of species details, performing better for large animals. When used together, these methods can be complementary.

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So Paulo is the most developed state in Brazil and contains few fragments of native ecosystems, generally surrounded by intensive agriculture lands. Despite this, some areas still shelter large native animals. We aimed at understanding how medium and large carnivores use a mosaic landscape of forest/savanna and agroecosystems, and how the species respond to different landscape parameters (percentage of landcover and edge density), in a multi-scale perspective. The response variables were: species richness, carnivore frequency and frequency for the three most recorded species (Puma concolor, Chrysocyon brachyurus and Leopardus pardalis). We compared 11 competing models using Akaike`s information criterion (AIC) and assessed model support using weight of AIC. Concurrent models were combinations of landcover types (native vegetation, ""cerrado"" formations, ""cerrado"" and eucalypt plantation), landscape feature (percentage of landcover and edge density) and spatial scale. Herein, spatial scale refers to the radius around a sampling point defining a circular landscape. The scales analyzed were 250 (fine), 1,000 (medium) and 2,000 m (coarse). The shape of curves for response variables (linear, exponential and power) was also assessed. Our results indicate that species with high mobility, P. concolor and C. brachyurus, were best explained by edge density of the native vegetation at a coarse scale (2,000 m). The relationship between P. concolor and C. brachyurus frequency had a negative power-shaped response to explanatory variables. This general trend was also observed for species richness and carnivore frequency. Species richness and P. concolor frequency were also well explained by a second concurrent model: edge density of cerrado at the fine (250 m) scale. A different response was recorded for L. pardalis, as the frequency was best explained for the amount of cerrado at the fine (250 m) scale. The curve of response was linearly positive. The contrasting results (P. concolor and C. brachyurus vs L. pardalis) may be due to the much higher mobility of the two first species, in comparison with the third. Still, L. pardalis requires habitat with higher quality when compared with other two species. This study highlights the importance of considering multiple spatial scales when evaluating species responses to different habitats. An important and new finding was the prevalence of edge density over the habitat extension to explain overall carnivore distribution, a key information for planning and management of protected areas.

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A relatively large amount of variation occurs in the reproductive ecology of tropical snakes, and this variation is generally regarded as being a consequence of seasonality in climate and prey availability. In some groups, even closely related species may differ in their reproductive ecology; however, in others it seems to be very conservative. Here we explore whether characters related to reproduction are phylogenetically constrained in a monophyletic group of snakes, the subfamily Dipsadinae, which ranges from Mexico to southern South America. We provide original data on reproduction for Leptodeira annulata, Imantodes cenchoa, and three species of Sibynomorphus from southern, southeastern and central Brazil, and data from literature for other species and populations of dipsadines. Follicular cycles were seasonal in Atractus reticulatus, Dipsa, albifrons, Hypsiglena torquata, Leptodeira maculata, L. punctata, Sibynomorphus spp. and Sibon sanniola from areas where climate is seasonal. In contrast, extended or continuous follicular cycles were recorded in Dipsas catesbyi, D. neivai, Imantodes cenchoa, Leptodeira annulata, and Ninia maculata from areas with seasonal and aseasonal climates. Testicular cycles also varied from seasonal (in H. torquiata) to continuous (in Dipsa,5 spp., Leptodeira annulata, L. maculata, N. maculata, and Sibynomorphus spp.). Most dipsadines are small (less than 500 rum SVL), and females attain sexual maturity with similar relative body size than males. Sexual dimorphism occurred in terms of SVL and tail length in most species, and clutch size tended to be small (less than five eggs). Combat behavior occurs in Imantodes cenchoa, which did not show sexual size dimorphism. Reproductive timing, for both females and males, varied among species but in general there were no differences between the tribes of Dipsadinae in most of the reproductive characteristics, such as mean body size, relative size at sexual maturity, sexual size and tail dimorphism, duration of vitellogenesis or egg-carrying in oviducts.

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The order Scorpiones is one of the most cytogenetically interesting groups within Arachnida by virtue of the combination of chromosome singularities found in the 59 species analyzed so far. In this work, mitotic and meiotic chromosomes of 2 species of the family Bothriuridae were detailed. This family occupies a basal position within the superfamily Scorpionoidea. Furthermore, review of the cytogenetic data of all previously studied scorpions is presented. Light microscopy chromosome analysis showed that Bothriurus araguayae and Bothriurus rochensis possess low diploid numbers compared with those of species belonging to closely related families. Gonadal cells examined under light and in transmission electron microscopy revealed, for the first time, that the Bothriuridae species possess typical monocentric chromosomes, and male meiosis presented chromosomes with synaptic and achiasmatic behavior. Moreover, in the sample of B. araguayae studied, heterozygous translocations were verified. The use of techniques to highlight specific chromosomal regions also revealed additional differences between the 2 Bothriurus species. The results herein recorded and the overview elaborated using the available cytogenetic information of Scorpiones elucidated current understanding regarding the processes of chromosome evolution that have occurred in Bothriuridae and in Scorpiones as a whole.

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Hydrocoryne iemanja sp. nov. was found in an aquarium, growing on rhodoliths of coralline algae collected on the southeastern coast of Brazil (20 degrees 40`S 40 degrees 2`W). The colonies were reared through maturity in the laboratory. Each colony had up to 7 sessile, long and thin monomorphic zooids, very extensible and flexible, arising from a chitinous, hard dark-brown plate with minute spines. Medusae budded from near the basal part of hydrocaulus, and were released in immature condition, acquiring fully developed interradial gonads 5-7 days after release. Asexual reproduction by longitudinal fission was observed on the hydrocaulus of the polyps, both for those in normal condition and those with injuries. Fission started at the oral region, extending aborally, with a new hard plate formed in the basal part of hydrocaulus. When fission reached the new hard plate, the new polyp detached, becoming free and sinking to the bottom, starting a new colony. Detached polyps were morphologically indistinguishable from other polyps, being able to produce medusae. Mother and daughter polyps undertook subsequent fissions. This mode of longitudinal fission is distinct from other modes of longitudinal fission, a process known for a few species Of cnidarians. Further studies of this process may shed light on the understanding of the evolutionary pathways in Cnidaria and animals. Hydrocoryne iemanja sp. nov. is distinguishable from its two congeners by the distinct marginal tentacles of the medusae-short and with a median nematocyst knob-an unambiguous character useful even for the identification Of newly liberated medusae.

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Two new species of Pamphobeteus Pocock 1901 are described from Brazil: Pamphobeteus crassifemur sp. nov. and Pamphobeteus grandis sp. nov.; Pamphobeteus nigricolor, formerly described from Colombia, Ecuador and Bolivia, is recorded from Brazil and its distribution in Ecuador and Bolivia is questioned. A new type of stridulatory organ is described from legs III and IV of P. crassifemur sp. nov. The structure consists of spiniform setae. Stridulation occurs when the spider moves the legs III and IV, sometimes while shedding urticating hairs.

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Eight new species of the spider genus Chrysometa Simon, 1894 (Araneae, Tetragnathidae) are described and illustrated. Chrysometa nubigena n. sp., C. waikoxi n. sp., C. petrasierwaldae n. sp., C. santosi n. sp., C. yanomami n. sp., C. candianii n. sp., C. lomanhungae n. sp., and C. saci n. sp. Those species were collected in a study on the diversity of spider communities along altitudinal gradients in Brazilian Amazonia. C. saci was captured at the Serra do Tapirapeco (Barcelos), while all the other species are from the Pico da Neblina (Sao Gabriel da Cachoeira), the highest mountain in Brazil. We provide new records for C. boraceia, C. flava, C. guttata, C. minuta and C. opulenta, and we describe the male of C. minuta for the first time. We also present the first results on the diversity and altitudinal distribution of the species of Chrysometa at the Pico da Neblina and Serra do Tapirapeco. We sampled the first locality at six different elevations, and obtained 336 specimens distributed in 12 species. Richness and abundance, as well as relative importance peaked at the highest sites sampled (2,000 and 2,400 m). The three most abundant species showed a segregated distribution, being dominant or exclusively distributed in different altitudes. At the Serra do Tapirapeco, sampling at four different elevations up to 1200 m, we only obtained 40 individuals divided in four species, and there was no clear relation to altitude. Most of the new species were found at mid and high altitude sites, while species from lower altitude sites represented widespread species. The comparison with other neotropical spiders inventories highlights the high diversity recorded at Pico da Neblina, which could be assigned to the large environmental variation covered in this work and to the sampling of high-altitude environments. Inventories in the Andean region and other information in the literature also seem to support the association of Chrysometa with high altitude environments.