ABSTRACT The family Pycnothelidae comprises medium to small-sized spiders that construct silk tubes under stones or logs or dig burrows in open environments. In Argentina, Acanthogonatus centralis Goloboff, 1995 and Stenoterommata platensis Holmberg, 1881 are two species commonly found in central region, associated to the mountainous grasslands or to the La Plata River Basin. The Tandilia mountainous grassland is an extended belt located southeastern Buenos Aires province, Argentina. Although some pycnothelid spiders are distributed close to this mountainous system, they are not recorded in Tandilia. Through niche modeling we attempt to evaluate the influence of bioclimatic variables in shaping the distribution of these species and explore their absence in the mountainous belt under past, present and future climatic conditions. We found that Tandilia is a non-suitable area for the establishment of the populations of these species with the exception of Stenoterommata platensis under a future scenario of climatic change.
ABSTRACT Mangroves are coastal ecosystems that exist in the transition zone between terrestrial and marine environments, typical of tropical regions, and they occur in areas with frequent tidal submersion. These ecosystems shelter the species Rhizophora mangle L. (Rhizophoraceae), a mangrove tree that has rhizophores, stem projections that serve as a substrate for a variety of encrusting, sedentary animals and macroalgal species. This study was carried out in an estuarine mangrove on the Acaraú River, located in northeastern Brazil, with the aim of determining the benthic community stablished over R. mangle rhizophores. Accordingly, five trees of this species were chosen, and subsequently, three rhizophores were selected from each tree, totaling fifteen sampled rhizophores, from which all associated macrobenthos were removed. All collected organisms were identified and rhizophores were evaluated for species richness, composition, density, diversity, frequency, equitability and dominance. In addition, vertical zonation of the organisms in rhizophores was determined. The benthic community was characterized by the predominant presence of the phylum Mollusca (Bivalvia and Gastropoda) and the phylum Annelida (Polychaeta). We showed the existence of a vertical zonation of the organisms in the substrate. Understanding the community structure in the rhizophores can facilitate more detailed and experimental studies to comprehend the distribution and even the biological interactions in these environments.
Lotic ecosystems are biodiverse environments that form different mesohabitats suitable for some species of crustaceans, such as those of the genus Hyalella, endemic to the Americas. In the state of Santa Catarina, anew species- Hyalella insulae- was recently described- the first insular species of Hyalella in Brazil, on the island of Florianopolis. The species was identified in the Municipal Natural Monument of Lagoa do Peri (MONA), south of the island, which has a large source of freshwater in the state, consisting of two watersheds: Cachoeira Grande and Ribeirao Grande. This study aims to analyze the spatial distribution of H. insulae in two mesohabitats (backwater and rapids) of these watersheds. Specimens were sampled in stretches of rifles and pools between winter/2010 and summer/2012, in three 1st to 3rd order streams inserted in the two watersheds, totaling 192 samples. It was observed that most samples with the presence of H. insulae occurred in the Cachoeira Grande watershed. The mean total abundance of H. insulae was higher in the pools stretches of Cachoeira Grande streams when compared to Ribeirao Grande. In the streams of both watersheds, in addition to males and females, juveniles of H. insulae were collected, which demonstrates that the species is reproducing in these streams. In addition, a higher concentration of dissolved oxygen and lower values of water temperature, water velocity, electrical conductivity and alkalinity were observed in Cachoeira Grande stream. This study demonstrated the preference of H. insulae for pools stretches of streams in Cachoeira Grande, which has primary and dense vegetation, unlike Ribeirao Grande, where areas with secondary vegetation and evidence of anthropic actions are observed in the surroundings. Thus, this research demonstrated the importance of studies regarding the distribution of endemic species, as well as the conservation and preservation of island streams and their biota.
ABSTRACT The genus Platyrrhinus Saussure, 1860 is one of the most speciose within the Phyllostomidae family in the Neotropical region, with 19 documented species worldwide, nine of which are found in Brazil. Platyrrhinus guianensis Velazco and Lim, 2014 was first recorded in the Guiana Shield, followed by a record in the Brazilian Amazon. This study represents the second record of P. guianensis in Brazil, specifically in the Maranhão (MA) Amazon biome (Turiaçu/MA - 01°39’36”S and 45°22’12”W). Morphological, craniodental, and molecular characters were employed for species identification. The specimen exhibited a dark brown dorsal fur, a conspicuous wide and white dorsal stripe, dark gray ventral fur, a forearm length of 38.5 mm, a short skull without a fossa in the scaly root of the zygomatic arch, with two stylar cusps on the posterior crest of the upper second premolar, one stylar cusp on the anterior crest of the lower second premolar, and upper internal incisors bilobed and convergent. Molecular results supported the morphological identification, confirming the occurrence of P. guianensis in the Maranhão Amazon. Molecular results provide the first public sequence of P. guianensis for the 16S rRNA gene and a new sequence for the COI gene, which will be useful in future studies for the species. These results supported the morphological identification, confirming the occurrence of P. guianensis in the Maranhão Amazon. This record extends the known distribution of this species approximately 1428.32 km to the east within the Amazon biome in Brazil.
Grazing intensity is one of the main factors that shape vegetation structure, influencing the grassland bird community. Tall grass birds, including several threatened species, are depending on low intensities or exclusion of grazing, which is rarely practiced in Pampa. In this study we evaluate how grazing intensities affects the bird community in Brazilian Pampa grasslands. We established three transect lines, one each grazing treatment (moderate and low intensity, and on an area with cattle exclusion). During 13 months, transects were sampled monthly to record the diversity and abundance of bird species. All three areas presented very similar species richness, ranging from 50 to 54 species, and diversity (H') ranging from 2.79 to 2.95. The abundance was favored by the decrease in intensity and the exclusion of grazing. In general, shortgrass bird species were more representative in the area under moderate grazing, while tallgrass birds were favored by low intensity and grazing exclusion. The taller and denser vegetation, in areas less impacted by livestock, was especially important for endangered species, such as Culicivora caudacuta Vieillot, 1818 and Sporophila cinnamomea Lafresnaye, 1839, providing shelter, perches and substrate for building and fixing nests. We corroborate the need for areas with distinct grazing intensities, forming a mosaic with different heights of vegetation, maintaining the grassland bird diversity. However, more areas with low intensity or exclusion of grazing are needed, on which several threatened species depend. Although, even these areas must be managed, avoiding the encroachment of excessive woody vegetation, which can lead to the deterioration of grassland vegetation, affecting the associated birdlife.
ABSTRACT The mangrove ecosystems are characterized by being one of the most productive, despite their poor soils, finding a great faunal richness. Meanwhile, pseudoscorpions are arachnids that inhabit all terrestrial ecosystems, and diverse in the tropics and subtropics. We evaluated the relationship of pseudoscorpions composition in mangrove forest fragments in the southern Gulf of Morrosquillo, using different metrics related to vegetation and land use. A total of 1063 individuals were collected, distributed in four families and eight species. Three indicator species of good conservation status were identified, Pachyolpium isolatum (Beier, 1931) a good indicator (A = 1.0; B = 0.93; p <0.001), and four detecting species of disturbed mangroves. The proximity to urban and tourist areas influences the composition of the community of the pseudoscorpion. The indicator capacity and the sensitivity demonstrated by the species make them a valuable argument and are considered as a tool that can indicate promptly the negative effects of certain management practices in the different mangrove forest fragments in the southern Gulf of Morrosquillo.
The Lear's Macaw (Anodorhynchus leari Bonaparte, 1856) is a Brazilian parrot globally threatened by extinction. Despite its threatened status (endangered), there is a scarcity of studies on its behavior. Understanding the behavior of this species is crucial to prevent inaccuracies in management and conservation strategies. This study aimed to delineate the behavioral repertoire of Lear's Macaw individuals residing at the Funda & ccedil;& atilde;o Parque Zool & oacute;gico de S & atilde;o Paulo under two distinct conditions: paired and in flocking. From September 2014 to February 2016, we conducted direct observations using all-occurrences sampling. An ethogram was compiled, encompassing 65 behavioral acts categorized into ten groups: maintenance, rest, locomotion, exploration, feeding, vigilance, socio-agonistic, socio-affiliative, reproduction, and stereotypic behaviors. Additionally, six vocalizations were identified based on spectrograms and associated with specific behavioral contexts: alarm, contact, pair cohesion, reproduction, and imitation. These findings provide a comprehensive overview of Lear's Macaw behavior in captivity. The ethogram and vocalization descriptions serve as a foundational resource for future studies, facilitating the refinement of tools employed in the conservation efforts for this species.
Symbiotic relationships are associations where two or more species live closely associated, including parasitism, phoresis, mutualism, and others. In mites, one of the most common associations occurs between larvae of Leptus (Erythraeidae), a cosmopolitan genus that parasitizes several groups of arthropods. However, in Brazil, these reports are scarce. In the present study, we recorded the number of ectoparasitic erythraeid mite larvae of the genus Leptus found associated to Opiliones of the species Gonyleptes fragilis Mello-Leitao, 1923 (Gonyleptidae) in an Atlantic Forest fragment (Cubatao, Sao Paulo, Brazil), collected over one year, between the four seasons. We recorded 405 mite larvae associated with 152 opilionid individuals. The intensity and prevalence of mite's infection, seasonal variation, mite's preference for body parts and host sex were the parameters used to determine host-parasite relationship. Mean infestation intensity (number of mites per individual) ranged from 0.3 to 11.3 with maximum observed intensity of 20 mites/individual. There was no sexual host preference and regarding seasonality, there were differences between infestation intensity and season with infestation being higher in summer compared to the other seasons. As for location, most mites were found in the median region of the dorsal shield, near the median frame of area III and IV. This study provides the first description of annual and seasonal variation in mite infestation on Opiliones in the Brazilian Atlantic Forest.
ABSTRACT This study aimed to assess population and reproductive aspects of the ampithoid amphipod Cymadusa filosa Savigny, 1816 in a region with pollution by petrogenic hydrocarbons. Sampling of Sargassum furcatum Kützing, 1843 fronds and the associated fauna was conducted in March, September and December 2007 and February 2008, on four rocky shores located on São Sebastião Island, southeastern Brazil. A total of 1372 specimens of C. filosa were recorded, including 934 juveniles, 274 females (60 ovigerous) and 164 males. Population mean density ranged from 1.27 to 6.40 ind/g with higher mean values in March 2007 and lower in December 2007 and February 2008. The total body length of males varied from 4.11 to 20.75 mm and of females from 3.58 to 20.22 mm. No significant difference was detected between male and female body length. The overall sex ratio significantly differed from 1:1 proportion and was skewed toward females (0.60:1). Ovigerous females occurred in higher proportion in February 2008 and presented mean fecundity of 26.01 ± 1.84 eggs/female (mean ± se), with great variation in the number of eggs found in the marsupium (between 1 and 56). Fecundity increased significantly with increasing female body length. The C. filosa population structure and reproduction were similar to those of populations in other locations, in Brazil and abroad indicating that pollution by petrogenic hydrocarbons in the São Sebastião Channel did not affect the population parameters of C. filosa in this region.
ABSTRACT Insects of the Ephemeroptera order have been used as bioindicators of water quality as they respond to countless anthropic impacts. In this study, we assessed the use of Ephemeroptera as bioindicators of streams impacted by agricultural activities. We collected Ephemeroptera nymphs in six streams with different uses and soil cover in their drainage areas located in the northern region of the Brazilian state of Rio Grande do Sul. Based on soil use and cover analysis, we categorized the streams as ‘natural’ (drainage area with >42% native arboreal vegetation) and ‘agricultural’ (drainage area with >72% agricultural use). We collected a total of 2,767 organisms, distributed into four families and eleven genera. We observed greater abundance (68%) and taxonomic richness (11 genera) of Ephemeroptera in the agricultural streams. The natural streams comprise 32% of the fauna collected, with eight genera. That pattern was especially determined by the Baetidae and Leptohyphidae families. The genera Caenis, Cloeodes, and Tricorythopsis were abundant in the agricultural streams. In this study, we observed that genera of Ephemeroptera are tolerant to environmental changes, particularly those caused by agricultural activities. Therefore, the use of the order in studies to assess water quality must be carried out with caution.
ABSTRACT In this work, the population dynamics and reproductive aspects of two sympatric Hyalella species in a river spring were analyzed in the northwestern state of Rio Grande do Sul, Brazil. The samplings were performed by one person, for ten minutes and using a hand net for one-year period (March 2018 to April 2019) and transported to the laboratory. All individuals sampled were sexed, measured, and separated by cephalothorax length (CC) size classes. Hyalella gauchensis Streck & Castiglioni, 2017 was 22.7 times more frequent and showed significantly greater mean cephalothorax when compared to Hyalella longipropodus Limberger, Graichen & Castiglioni, 2021. Males had a larger body size (CC) than females, although they occur in smaller numbers in both species. The total frequency distribution in CC size classes was bimodal in males and juveniles, and polimodal in females of H. gauchensis. In H. longipropodus the distribution as bimodal in males, females and juveniles. Both H. gauchensis and H. longipropodus had their breeding season and recruitment during the colder seasons of the year (fall and winter, respectively). However, there was a seasonal temporal separation of the intensity peaks between the two species, which could indicate different strategies and/or evolutionary adaptations for their coexistence.
ABSTRACT This is paper we analyze the diet and body condition factor (Mi) of three endemic species inside and outside an environmental protection area, to compare the effectiveness of the protection area in providing a greater spectrum of food items and greater environmental well-being to ichthyofauna. The study area comprised streams of the Ribeira do Iguape River basin, Campos Gerais National Park (CGNP), Paraná state and its surroundings. Eleven streams were sampled inside and outside, using electric fishing. A Permutational Multivariate Analysis of Variance to investigate the composition of food items and a Permutational Analysis of Multivariate Dispersions was used to investigate the variability between food items. The Scaled Mass Index (Mi) of the body condition was used to determine the relative condition factor of each individual of each species. Regarding the diet, there were no significant differences between inside and outside in the composition and variability of food items, this similarity may be associated with existing environmental degradation inside. However, the Mi was significant, and only one species presented greater well-being inside, because inside streams receive greater allochthonous intake of riparian vegetation, but, when it comes to the two species that perform the link of the aquatic food web with the terrestrial, the opposite occurred. These results indicate that the studied fragment, under anthropic pressures, is currently unable to conserve its biodiversity. The inside has no Management Plan, the manager must elaborate and implement it as a first step so that the situation can be reverted and the conservation effectiveness ensured in this highly threatened area, characterized by being one of the most important remnants of the Atlantic Forest, having relevant ecosystem services from a rare humid forest of Araucaria.
Neoptychodes hondurae trivittatus (Taschenberg, 1870) is synonymized with N. hondurae (White, 1858). The holotype of the former is illustrated for the first time. The identity of the holotype of N. cosmeticus Martins & Galileo, 1996 is commented. All species of Neoptychodes Dillon & Dillon, 1941 are illustrated and a key to species of the genus is provided.
ABSTRACT. Two muriqui species are currently described in the literature: the southern muriqui, Brachyteles arachnoides (E. Geofroy, 1806) and the northern muriqui, Brachyteles hypoxanthus (Kuhl, 1820). Nowadays, the distribution of the southern muriqui is restricted to forest patches of the states of Rio de Janeiro, São Paulo and Paraná, while the northern muriqui occurs in Espírito Santo, Bahia and Minas Gerais. Both are threatened species, but there are still many gaps in our knowledge of their occurrence, especially for southern muriquis in the state of RJ. The purpose of this work is precisely to identify the primary areas of occurrence of the muriqui in Rio de Janeiro through historical reports by naturalists, adventurers and others since the 16th century. Thus, allowing to assist in the establishment and conservation strategies of the species.
ABSTRACT The widely distributed species, Stenochrus portoricensis Chamberlin, 1922, is recorded for the first time from Costa Rica and Venezuela, and new occurrences from Brazil and Colombia are presented. Morphology of spermathecae from 14 localities is compared and illustrated. The need for studies to evaluate the potential status as an invasive species of S. portoricensis is commented on and a distribution map of the species in southern Central America and South America is given.
ABSTRACT The identity of the bird described from Paraguay by Félix de Azara as No. 372 Ypacahá del Pardo is confirmed as the immature plumage of the Spotted Rail Pardirallus maculatus maculatus (Boddaert, 1783). This description is the basis for the name Rallus rytirhynchos Vieillot, 1819 which is thus a junior subjective synonym and an available name. Rallus rytirhynchos Vieillot, 1819 is the type species of the genus Ortygonax Heine, 1890. Ortygonax Heine, 1890 is a junior subjective synonym of Pardirallus Bonaparte, 1856 and is also available for application.
RESUMO O jacurutu Bubo virginianus (Gmelin, 1788) tem ampla distribuição pela América, estendendo-se desde o Alasca e norte do Canadá, até o centro da Argentina e Uruguai. Apesar de relativamente comum, diferentes aspectos da história natural desta espécie ainda permanecem pouco conhecidos, sobretudo na Região Neotropical. Assim, o objetivo deste trabalho foi obter informações referentes à área de vida utilizada por B. virginianus, sua biologia reprodutiva e dieta no Pampa brasileiro. O estudo foi realizado entre abril de 2015 e abril de 2018, no município de Santa Margarida do Sul, região central do Pampa brasileiro, Rio Grande do Sul, Brasil. A área de estudo conta com capões de Eucaliptus spp., sob os quais a vegetação é predominantemente formada por gramíneas, com manchas de arbustos espinhosos em pontos específicos. Os arredores do capão principal são utilizados para criação extensiva de gado em campo nativo além de cultivos de soja e arroz. A coleta de dados foi baseada no acompanhamento visual dos indivíduos com ao menos uma observação quinzenal durante o período não reprodutivo, e ao menos uma observação semanal durante o período de utilização do ninho. Além do ninho, foram verificados os poleiros de descanso dos indivíduos monitorados e coletadas as egagrópilas regurgitadas, para posterior estudo de seus hábitos alimentares. A área de vida utilizada pelo casal foi estimada em 0,35 km² pelo método do MCP, ou 0,41 km² baseado em estimativas pelo método de Kernel. Os indivíduos parecem demonstrar interesse por locais limítrofes da área de vida durante a noite e preferindo a parte central da mesma para abrigo/descanso durante o dia. O tempo de utilização do ninho foi de três meses em todos os períodos reprodutivos. A estação reprodutiva da espécie está relacionada ao pico do inverno, com um a dois filhotes nascendo próximo ao final da estação. Os filhotes permaneceram na área de vida dos pais por um período de sete até dez de meses, dispersando durante os meses do outono do ano seguinte. Por fim, a dieta foi baseada em roedores, sobretudo Holochilus vulpinus (Brants, 1827) e aves, seguindo um padrão já conhecido para espécie.
The aim of the present study was to investigate the effect of dredging activities on the structure of the macrobenthic community of a port complex in São Luís do Maranhão (2°S, Brazil). Sampling was performed on four occasions: pre-dredging, dredging 1 (25% of the material dredged), dredging 2 (75% of the material dredged) and post-dredging. Total mean density was 430.8 ± 55.0 ind/m², with 147.76 ± 280.82 ind/m² at pre-dredging, 161.90 ± 285.67 ind/m² at dredging 1, 53.83 ± 72.15 ind/m² at dredging 2 and 67.29 ± 72.58 ind/m² after dredging, revealing a reduction during dredging 2. The most representative groups were Polychaeta, Oligochaeta, Crustacea and Mollusca. Lumbrineris sp. (Polychaeta) was present in all sampling periods and was the dominant species. Richness and Shannon diversity of the species were higher in the pre-dredging and post-dredging periods, with reductions during the dredging activities (dredging 1 and 2). Principal component analysis revealed a correlation with granulometry and heavy metals in the sediment. The dredging activities led to a reduction in the macrobenthic community. Moreover, post-dredging recovery was insufficient for the recovery of the community.
The aim of this study was to characterize the population and reproductive biology of the terrestrial and exotic amphipod Talitroides topitotum (Burt, 1934) in a forested area of the Universidade Federal de Santa Maria, Campus Palmeira das Missces, state of Rio Grande do Sul. The samplings were carried out monthly (April/2015 to March/2016) using pitfall traps that were installed on four transects (five traps in each), totalizing 20 collecting units/area. A total of 2,948 amphipods were collected: 1,066 juveniles (36.16%), 1,882 females (63.84%) from which 258 ovigerous females (8.7%). The monthly abundance of individuals varied considerably, a high relative frequency was observed in the colder seasons, with 28.9% of the individuals sampled in autumn and 58.4% in winter. Ovigerous females are significantly larger than non-ovigerous females. Frequency distribution in size classes was not normal for juveniles, non-ovigerous females and ovigerous females. The reproductive and recruitment periods were seasonal, with a peak in winter followed by autumn. Fecundity of T. topitotum varied from 1 to 8 eggs, mean of 3.54 & PLUSMN; 1.33 per female. The results of the reproductive and recruitment periods of T. topitotum in Palmeira das Missces showed in this work demonstrate that the species seems to be stable, with the presence of ovigerous females and juveniles, which proves that the species is reproducing in the area, although no males were sampled throughout the year.
ABSTRACT In this paper a new species of Diphya Nicolet, 1849, D. napo sp. nov. is described based on males and females from Ecuador. The female of Diphya bicolor Vellard, 1926 is described and illustrated for the first time and new records are presented. Oarces ornatus Mello-Leitão, 1935 and Azilia eximia (Mello-Leitão, 1940) are synonymized with D. bicolor, being A. eximia removed from the synonym of Azilia Keyserling, 1881 and being Cardimia Mello-Leitão, 1940 considered synonym of Diphya.
