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Ergasilus tipurus n. Sp. (copepoda: Ergasilidae), a parasite of Brazilian amazon fish species
No full textIntroduction Copepods are common components in all types of fish assemblages, being present in fishes of all ecosystems. The Ergasilidae Burmeister, 1835 is one of the biggest families in the order Cyclopoida Burmeister, 1834, with the majority of species found on freshwater fishes. Material and methods Ergasilus tipurus n. sp. is described from the nasal fossae of Calophysus macropterus and Sorubim lima captured in the rivers Guaporé and Mamoré in the State of Rondônia, Brazil, and from the nasal fossae and the gills of Rhaphiodon vulpinus collected from floodplain lakes of the Solimões River in the State of Amazonas, Brazil. Results The new species differs from all known species of Ergasilus from Brazilian waters by: (1) antennule setal formula 3:7:3:4:2:5; (2), having three-segmented first endopod of leg I; and (3) having leg V with a single well-developed segment with one middle distal setae, two distal setae placed laterally and two basal papillae, each provided with a simple seta. Discussion From all Ergasilus species described in the neotropics, this is the first species that can be found parasitizing the gills and nasal fossae of the reported hosts. © Witold Stefański Institute of Parasitology, Polish Academy of Sciences 2019
Cryptococcus gattii VGII isolated from native forest and river in Northern Brazil
No full textBackground: Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. In the northern region of Brazil, this disease is caused by Cryptococcus neoformans genotype VNI and Cryptococcus gattii genotype VGII. However, few environmental studies have been conducted in this large tropical area. Aims: This study was performed to isolate, genotype, and determine the frequency of cryptococcal agents in environmental samples near Manaus, Amazonas, Brazil. Methods: A total of 970 environmental samples (290 from soil, 290 from decaying plants, 5 from insects, 280 from the Negro river, and 105 from small streams within the city of Manaus) were collected and plated on Niger seed agar. In addition, 20 sub-cultures obtained from each positive sample were analyzed by PCR-RFLP (URA5) and PCR for genotyping and determination of mating type. Results: Six samples were positive for isolates from the C. gattii species complex. Of those, three samples were from Adolpho Ducke Forest Reserve and three were from the Negro river. All isolates were C. gattii genotype VGII (mating type MATα). Conclusion: Genotype VGII proved to be the most important genotype found in the environmental samples. The genotype VGII has been described as one of the most virulent and less susceptible to antifungals and responsible for important outbreaks. This is the first study to demonstrate isolation of C. gattii (VGII) from the Negro river. © 2019, Sociedade Brasileira de Microbiologia
Anuran species composition from Chaco and Cerrado areas in Central Brazil
Get PDFHerein, we present an updated inventory and the variations of frog communities’ composition from five areas of humid Chaco and Cerrado in municipality of Porto Murtinho, Mato Grosso do Sul state, Brazil. This municipality is located in an area with three ecoregions: Chaco, Cerrado and Pantanal. Through acoustic and visual nocturnal/diurnal and pitfall evaluations from a period of over five years, we recorded 31 species in the Cerrado and 29 species in the humid Chaco. About 90% of the species were previously registered in the municipality of Porto Murtinho. A non-metric multidimensional analysis based on a presence/absence matrix revealed a separation in our sampling sites and communities with Cerrado and humid Chaco characteristics. This peculiarity in the species composition must be related to the transition zone, with the presence of mixed species characteristics of Cerrado and humid Chaco in both areas in the municipality of Porto Murtinho experiences a high degree of deforestation pressure, which threatens both the Cerrado and humid Chaco vegetation. This highlights the importance of knowledge actions about the richness and composition of species, corroborating ecological tools to support conservation in this region. © 2019, Universidade Federal do Rio de Janeiro (UFRJ). All rights reserved
Three bird species new to Brazil from the serra da mocidade, a remote mountain in Roraima
Get PDFFrom 15 January to 06 February 2016, we conducted an expedition to the Serra da Mocidade, a remote and previously unexplored mountain range in extreme northern Amazonian Brazil. There we encountered three bird species never before documented in Brazilian territory: Grallaria guatimalensis (Grallariidae) was photographed, audio recorded, video recorded and a single specimen collected; Catharus aurantiirostris (Turdidae) was similarly documented and a series of specimens collected; and a single individual of Parkesia motacilla (Parulidae) was photographed. All were found in the understory of montane forest at 1000–1550 m elevation. We interpret each of these as most likely representing a regularly occurring population on Mocidade. However, each had probably been overlooked in Brazil for a different reason and represents a distinct distributional pattern. Adding these novelties to Brazil's previously published total of 1919 species clearly expresses the country's position among the most bird-rich in the world, perhaps the richest, and suggests that further exploration of Brazil's Amazonian mountains will yield more discoveries. © 2019, Sociedade Brasileira de Ornitologia. All rights reserved
O uso do valor calórico das sementes de Eugenia stipitata no crescimento da raiz e parte aérea sob condições ambientais adversas
No full textScreening and antifungal activity of a β-carboline derivative against cryptococcus neoformans and C. gattii
Get PDFBackground. Cryptococcosis is a fungal disease of bad prognosis due to its pathogenicity and the toxicity of the drugs used for its treatment. The aim of this study was to investigate the medicinal potential of carbazole and β-carboline alkaloids and derivatives against Cryptococcus neoformans and C. gattii. Methods. MICs were established in accordance with the recommendations of the Clinical and Laboratory Standards Institute for alkaloids and derivatives against C. neoformans and C. gattii genotypes VNI and VGI, respectively. A single active compound was further evaluated against C. neoformans genotypes VNII, VNIII, and VNIV, C. gattii genotypes VGI, VGIII, and VGIV, Candida albicans ATCC 36232, for cytotoxicity against the MRC-5 lineage of human fibroblasts and for effects on fungal cells (cell wall, ergosterol, and leakage of nucleic acids). Results. Screening of 11 compounds revealed 8-nitroharmane as a significant inhibitor (MIC 40 μg/mL) of several C. neoformans and C. gattii genotypes. It was not toxic to fibroblasts (IC 50 > 50 μg/mL) nor did it alter fungal cell walls or the concentration of ergosterol in C. albicans or C. neoformans. It increased leakage of substances that absorb at 260 nm. Conclusions. The synthetic β-carboline 8-nitroharmane significantly inhibits pathogenic Cryptococcus species and is interesting as a lead compound towards new therapy for Cryptococcus infections. © 2019 Kátia Santana Cruz et al
The Munduruku marmoset: A new monkey species from southern Amazonia
Get PDFAlthough the Atlantic Forest marmosets (Callithrix spp.) are among the best studied Neotropical primates, the Amazonian marmosets (Callibella humilis, Cebuella spp. and Mico spp.) are much less well-known. Even species diversity and distributions are yet to be properly determined because field data and materials currently available in scientific collections do not allow comprehensive taxonomic studies of Amazonian marmosets. From 2015 to 2018, we conducted 10 expeditions in key-areas within southern Amazonia where little or no information on marmosets was available. In one such region-the Tapajós-Jamanxim interfluve-we recorded marmosets with a distinctive pelage pigmentation pattern suggesting they could represent a new species. We tested this hypothesis using an integrative taxonomic framework that included phylogenomic data (ddRAD sequences), pelage pigmentation characters, and distribution records. We found that the marmosets of the northern Tapajós-Jamanxim interfluve have unique states in pelage pigmentation characters, form a clade (100% support) in our Bayesian and Maximum-Likelihood phylogenies, and occur in an area isolated from other taxa by rivers. The integration of these lines of evidence leads us to describe a new marmoset species in the genus Mico, named after the Munduruku Amerindians of the Tapajós-Jamanxim interfluve, southwest of Pará State, Brazil. Copyright © 2019 Costa-Araújo et al
Effects of forest fragmentation on community patterns of social wasps (Hymenoptera: Vespidae) in Central Amazon
No full textLandscape fragmentation is one of the greatest threats to environments globally, affecting all living organisms within fragments at many assembly levels. Despite such general assumptions, very few reports exist on the diversity patterns of Amazonian social wasps (Polistinae) in response to fragmentation. Our study aims at addressing how the community patterns of social wasp change from continuous to fragmented landscapes in the Amazon rainforest. We collected social wasps for a year (11 520 trap-hour effort) in a continuous forest and a highly disturbed urban forest fragment, located in Manaus, Brazil. We attracted wasps using sardine and orange juice traps, placed in 20 sampling plots. We collected 2742 wasps from 29 species. Agelaia pallipes, Angiopolybia pallens and Agelaia fulvofasciata were the most abundant species. We detected significant differences in overall abundance, species richness and species composition of social wasps between landscapes. Conversely, no difference in species diversity (effective number of species) was found between habitats. Despite the low quantity of exclusive species, the numbers of most species declined sharply in the fragmented habitat, while for one species (Polybia rejecta), abundance increased. Regarding the percentile of species contribution to dissimilarity between landscapes, five out of the first six species were highly abundant (>100 individuals), thus demonstrating that the observed pattern was very likely driven by common species. Additionally, our findings highlight that fragmentation threatens abundant species as much as rare species. We hope that our results encourage the use of social wasps as models in basic and applied ecological surveys and further efforts for conservation of pristine forest areas in the tropical region of South America. © 2018 Australian Entomological Societ
