Abstract in English:This work describes the foraging techniques, body positions and behavior of free-ranging Ingram's squirrel Guerlinguetus ingrami Thomas, 1901 in a region of the Araucaria moist forest, in the Atlantic Forest of southern Brazil. The animals were observed using the "all occurrence sampling" method with the aid of binoculars and a digital camcorder. All behaviors were described in diagrams and an ethogram. We recorded five basic body positions, 24 behaviors, two food choices, and three feeding strategies utilized to open fruits of Syagrus romanzoffiana (Cham.), the main food source of Ingram's squirrels. We also observed a variance in the animals' stance, which is possibly influenced by predation risk, and discuss the causes of some behaviors.
Abstract in English:Aeglids are freshwater anomurans that are endemic from southern South America. While their population biology at the species-level is relatively well understood, intraspecific variation within populations has been poorly investigated. Our goal was to investigate the population biology of Aegla platensis Schmitt, 1942 from the Uruguay River Basin, and compare our data with data from other populations. We estimated biometric data, sex ratio, population density and size-class frequencies, and frequencies of ovigerous females and juveniles, from the austral spring of 2007 until autumn 2008. Sexual dimorphism was present in adults, with males being larger than females. Furthermore, males and females were significantly larger than previously recorded for the species. The overall sex ratio was 1.33:1 (male:female), and population density ranged from 1.8 (spring) to 3.83 ind.m-² (winter). Data from this population differ from published information about A. platensis in almost all parameters quantified except for the reproductive period, which happens in the coldest months, and a population structure with two distinct cohorts. Difference among studies, however, may be in part due to methodological differences and should be further investigated in order to determine their cause. In addition to different methodologies, they may result from ecological plasticity or from the fact that the different populations actually correspond to more than one species.
Abstract in English:The greatest current threat to terrestrial fauna is continuous and severe landscape modification that destroys and degrades animal habitats. This rapid and severe modification has threatened species, local biological communities, and the ecological services that they provide, such as seed dispersal, insect predation, and pollination. Bats are important pollinators of the Cerrado (woodland savanna) because of their role in the life cycles of many plant species. However, there is little information about how these bat species are being affected by habitat loss and fragmentation. We used radio-tracking to estimate the home ranges of Glossophaga soricina (Pallas, 1776) and Lonchophylla dekeyseri Taddei, Vizotto & Sazima, 1983. The home range of G. soricina varies from 430 to 890 ha. They combine shortrange flights of up to 500 m to nearby areas with longer flights of 2 to 3 km that take them away from their core areas. The maximum flight distance tracked for L. dekeyseri was 3.8 km, and its home range varies from 564 to 640 ha. The average distance travelled by this species was 1.3 km. Our data suggest that G. soricina and L. dekeyseri are able to explore the fragmented landscape of the Central Brazilian Cerrado and that they are likely to survive in the short- to medium-term. The natural dispersal ability of these two species may enable them to compensate for continued human disturbance in the region.
Abstract in English:We conducted a study on shell morphology variation among three populations of Happiella cf. insularis (Boëttger, 1889) inhabiting different areas (Jararaca, Caxadaço, and Parnaioca trails) at Vila Dois Rios, Ilha Grande, Angra dos Reis, state of Rio de Janeiro, Brazil. Linear and angular measurements, shell indices representing shell shape, and whorl counts were obtained from images drawn using a stereomicroscope coupled with a camera lucida. The statistical analysis based on ANOVA (followed by Bonferroni's test), Pearson's correlation matrix, and discriminant analysis enabled discrimination among the populations studied. The variable that most contributed to discriminate among groups was shell height. Mean shell height was greatest for specimens collected from Jararaca, probably reflecting the better conservation status of that area. Good conservation is associated with enhanced shell growth. Mean measurements were smallest for specimens from Parnaioca, the most disturbed area surveyed. Mean aperture height was smallest for specimens from Parnaioca, which may represent a strategy to prevent excessive water loss. Discriminant analysis revealed that the snails from Jararaca differ the most from snails collected in the two other areas, reflecting the different conservation status of these areas: shells reach larger sizes in the localities where the humidity is higher. The similarities in shell morphology were greater between areas that are more similar environmentally (Caxadaço and Parnaioca), suggesting that conchological differences may correspond to adaptations to the environment.
Abstract in English:Species richness and geographical distribution of Cyclopoida freshwater copepods were analyzed along the "La Plata" River basin. Ninety-six samples were taken from 24 sampling sites, twelve sites for zooplankton in open waters and twelve sites for zooplankton within macrophyte stands, including reservoirs and lotic stretches. There were, on average, three species per sample in the plankton compared to five per sample in macrophytes. Six species were exclusive to the plankton, 10 to macrophyte stands, and 17 were common to both. Only one species was found in similar proportions in plankton and macrophytes, while five species were widely found in plankton, and thirteen in macrophytes. The distinction between species from open water zooplankton and macrophytes was supported by nonmetric multidimensional analysis. There was no distinct pattern of endemicity within the basin, and double sampling contributes to this result. This lack of sub-regional faunal differentiation is in accordance with other studies that have shown that cyclopoids generally have wide geographical distribution in the Neotropics and that some species there are cosmopolitan. This contrasts with other freshwater copepods such as Calanoida and some Harpacticoida. We conclude that sampling plankton and macrophytes together provided a more accurate estimate of the richness and geographical distribution of these organisms than sampling in either one of those zones alone.
Abstract in English:Community-level network studies suggest that seed dispersal networks may share some universal properties with other complex systems. However, most of the datasets used so far in those studies have been strongly biased towards temperate birds, including not only dispersers, but also seed predators. Recent evidence from multi-taxon networks suggests that seed dispersal networks are not all alike and may be more complex than previously thought. Here, we used network theory to evaluate seed dispersal in a strongly impacted Atlantic Forest fragment in northeastern Brazil, where bats and birds are the only extant dispersers. We hypothesized that the seed dispersal network should be more modular then nested, and that the dispersers should segregate their services according to dispersal syndromes. Furthermore, we predicted that bat and bird species that are more specialized in frugivory would be more important for maintaining the network structure. The mixed network contained 56 plant species, 12 bat species, and eight bird species, and its structure was more modular (M = 0.58) then nested (NODF = 0.21) compared with another multi-taxon network and 21 single-taxon networks (with either bats or birds). All dispersed fruits had seeds smaller than 9 mm. Bats dispersed mainly green fruits, whereas birds dispersed fruits of various colors. The network contained eight modules: five with birds only, two with bats only, and one mixed. Most dispersers were peripheral, and only specialized frugivores acted as hubs or connectors. Our results strongly support recent studies, suggesting that seed dispersal networks are complex mosaics, where different taxa form separate modules with different properties, which in turn play complementary roles in the maintenance of the associated ecosystem functions and services.
Abstract in English:Evidence that the bill of the Toco Toucan, Ramphastos toco Statius Muller, 1776, has a specialized role in heat dissipation suggests a new function for the large and light-weight bill of the toucan family (Piciformes: Ramphastidae). A prediction of this hypothesis is that bill length in toucans will increase with body mass at a rate greater than the isometric expectation. This hypothesis was tested in a phylogenetic context with measurements of skeletal elements in adult males of 21 toucan species. In these species, 64.3% of variance in relative skeletal measurements was accounted for by the contrast between bill and body size. Maxilla length and depth increased with body mass at a greater than isometric rate relative to both body mass and other linear skeletal measures. By contrast, no such trend was seen in a parallel analysis of 24 hornbill species (Bucerotiformes), sometimes considered ecological equivalents of toucans. The unique relationship between bill size and body mass in toucans supports the hypothesis that the evolution of a heat dissipation function has been a persistent theme of bill evolution in toucans.
Abstract in English:Eupanthalis rudipalpa Amaral & Nonato, 1984 was described based on three incomplete, colorless specimens and has not been reported since its original description; the epithet rudipalpa means "hirsute palps", a characteristic that separates it from other congeneric species. Eupanthalis McIntosh, 1876 and Euarche Ehlers, 1887, and their respective type species, E. kinbergi McIntosh, 1876 and E. tubifex Ehlers, 1887, were considered synonyms (E. rudipalpa as a junior synonym of E. tubifex, a cosmopolitan species) by some authors, because both have sessile eyes and two or three antennae. Nonetheless, these two genera are, in fact, distinct. Their type species can clearly be separated using some prostomial features. We provide an emended diagnosis of Euarche, and re-instate E. rudipalpa, redescribing it based on a Brazilian specimen (original type specimens lost). Illustrations showing body pigmentation pattern and a key to all species of Eupanthalis are also provided.
Abstract in English:Neoseiulus HUGHES, 1948 is currently one of the largest genus of Phytoseiidae Berlese. Neoseiulus demitei sp. nov., a new species of phytoseiid mite from Rio Grande do Sul State, Brazil, is illustrated and described based on specimens collected on Tibouchina sp. (Melastomataceae) plants. This new species differs from others by having most of propodossomal setae reaching the base of nearby setae and a constriction of ventrianal shield at level of preanal pores. Nevertheless, this new species is the first of the species subgroup kennetti described from Brazil. A key of Neoseiulus species reported in Brazil is also included.
Abstract in English:Dubiaranea argenteovittata Mello-Leitão, 1943 was described from the state of Rio Grande do Sul, Brazil, based on a female. We describe and illustrate the male of the species for the first time, and provide the first records for the states of Santa Catarina and Paraná. The redescription and illustrations of the female is based on the holotype and new material from the type locality. New distributional records are also provided for the state of Rio Grande do Sul.
Abstract in English:Arapona furcata sp. nov. is described and illustrated based on a male specimen from Peru, department of Madre de Dios. This species can be recognized by the following features: 1) styles without a concavity on the ventral margin; 2) aedeagus robust and with a pair of long and slender preatrial processes; and 3) aedeagus with two apical processes, each with a sharp and hook-like apex. A key to the three known species of the genus is added.
Abstract in English:Laelius Ashmead includes 54 known nominal species worldwide. We present a revision of the Neotropical species of Laelius and provide keys for the identification of males and females of these species. We propose fourteen nomenclatural changes and additions. For the Neotropics, seven new species from Brazil are described and illustrated: Laelius arryni sp. nov. which has clypeus bearing median lobe with apical margin straight; propodeal disc with inner discal carina complete; aedeagus with apical lobes touching each other and inner margin with hook-shaped process, L. baratheoni sp. nov. which has propodeal disc with second pair of discal carinae incomplete; genitalia with paramere wing-shaped; with long setae around the margin and cuspis wide, L. lannisteri sp. nov. which has median lobe of clypeus with apical margin straight; mesopleuron with mesopleural suture distinct; genitalia with paramere slender and angled, cuspis wide, L. martelli sp. nov. which has pronotum with series of foveae posteriorly; genitalia with paramere slender and placed dorsally, aedeagus not reaching apex of paramere, L. targaryeni sp. nov. which has head with clypeus wide and with apical margin rounded; propodeal disc without longitudinal ridge between median and inner discal carinae; forewing with r-rs & Rs longer than Rs+M, L. tullyi sp. nov. which has head densely punctate; pronotal disc, mesoscutum and mesoscutellum rugulose; mesopleuron with mesopleural suture not fused with posterior fovea, L. starki sp. nov. which has mesoscutellar sulcus straight; mesopleuron with all foveae closed; genitalia with paramere club-shaped and with aedeagus wide. For the Nearctic region, Laelius areolatus (Rosmann & Azevedo, 2005) is a new junior synonym of Laelius pedatus (Say, 1836) and lectotypes for L. rufipes Ashmead, 1893, L. nigripilosus Ashmead, 1893, L. tricarinatus Ashmead, 1893, L. trogodermatis Ashmaed, 1893, and Mesitius nigripilosus Ashmead, 1895 are designated. We also propose the name Laelius billi Barbosa & Azevedo nom. nov. for Mesitius nigripilosus Ashmead, 1895 and re-erect Laelius huachucae (Evans, 1965) from L. nigripilosus (Ashmead, 1895). As result, Laelius now includes 61 species, 15 of which are from the Neotropical region.