Ephemeroptera (Insecta) from the metropolitan region of Santarém, Pará, Brazil / Ephemeroptera (Insecta) da região metropolitana de Santarém, Pará, Brasil

Abstract With the objective of improving the knowledge about Ephemeroptera in the North region of Brazil, the group's first survey was carried out for the metropolitan region of Santarém, Pará, Brazil. The specimens analyzed were collected from 2019 to 2020 in 27 aquatic environments distributed in the region. The nymphs were captured in the streams with aquatic entomological nets, in addition to manual collection on the substrates. Adults were collected using light traps and flight intercept traps. To complement the inventory, a bibliographic survey of species previously recorded in the area was carried out. For this, the Taxonomic Catalog of Fauna of Brazil, the website Ephemeroptera in South America and scientific articles were consulted. As a result, eight families, 23 genera and 31 species/morphospecies were recorded for the region, with 13 new records for Pará and 19 for the metropolis of Santarém. This study demonstrates the relevance of surveys for the knowledge of biodiversity and for understanding the geographic distribution of taxa.

Resumo Com o objetivo de aprimorar o conhecimento sobre Ephemeroptera na região Norte do Brasil, foi realizado o primeiro levantamento do grupo para a região metropolitana de Santarém, Pará, Brazil. Os espécimes analisados foram coletados de 2019 a 2020 em 27 ambientes aquáticos distribuídos na região. As ninfas foram capturadas nos riachos com redes entomológicas aquáticas, além da coleta manual nos substratos. Os adultos foram coletados por meio de armadilhas luminosas e armadilhas de interceptação de voo. Para complementar o inventário, foi realizado o levantamento bibliográfico das espécies previamente registradas na área. Para isso, foram consultados o Catálogo Taxonômico da Fauna do Brasil, o site Ephemeroptera na América do Sul e artigos científicos. Como resultado, oito famílias, 23 gêneros e 31 espécies/morfoespécies foram registradas para a região, sendo 13 novos registros para o Pará e 19 para a metrópole de Santarém. Este estudo demonstra a relevância dos levantamentos para o conhecimento da biodiversidade e para a compreensão da distribuição geográfica dos táxons.

Environmental integrity as a modeler of the composition of the Odonata community.

Human actions often alter natural environments, causing homogenization of micro-habitats and, consequently, the loss or replacement of species. Our research evaluates how the effects of environmental integrity and the physical and chemical characteristics of streams influence the adult Odonata community in a region of the Amazon, in western Pará. The data were obtained in 15 streams of first and second order in the municipality of Santarém, Pará, between October and December 2014 (dry season) and between March and May 2015 (rainy season). A total of 544 specimens were collected, distributed in 23 genera, 35 species. Significant differences were observed in the composition of Odonata based on the integrity of streams, and species are replaced as the habitat integrity gradient is reduced, with species that need more preserved conditions extinct locally, making room for generalist species. However, only Psaironeura tenuissima was an indicator of more preserved sites, while Argia sp.1 and Mnesarete smaragdina were indicative of altered sites. None of the variables had any influence on the richness or abundance of Odonata.

Contribution to the knowledge of Camillea (Ascomycota, Graphostromataceae) in the Amazon forest in Pará, Brazil

Three species of the Ascomycetes genus Camillea were recorded in a fragment of Amazon rainforest in the region of Santarém, Pará state, Brazil. The occurrence of C. leprieurii, C. cyclops and C. bilabiata expand the range of distribution of these species in the state. Camillea leprieurii has previous records in the regions of Marabá, Oriximiná, Itaituba and Novo Progresso, while C. cyclops had been recorded in the west of the state. This is the first record of C. bilabiata for Pará. We provide a morphological description of the specimens and an identification key for Camillea species found in Pará. (AU)

Morphology and distribution of the freshwater mussel Diplodon granosus, a rare and poorly understood species

Diplodon granosus was one of the first freshwater mussels to be described for South America. However, the status of the species was confusing for a long time, receiving different taxonomic treatments. In this paper, we redescribe the shell, with new data on the soft parts and information on the distribution and conservation of D. granosus, a rarely recorded species. The shell is thin, not inflated; the macrosculpture is composed only by granules that cover the whole shell, not forming bars; the microsculpture comprises short spikes. In the soft parts we highlight the few, weak and irregularly distributed lamellar connections of the outer demibranch and some features of the stomach, such as the distally enlarged minor typhlosole. There are records of D. granosus over a large area of South America, from Guiana to Argentina. However, most of these records are related to other species and the distribution of D. granosus is restricted to the north of South America in the basins of the Amazonas and Orinoco rivers, and coastal rivers in between. Despite this wide distribution, the species occurs in specific habitats, mainly streams (igarapés), resulting in an extremely fragmented occurrence. Thus, any disturbance to these habitats can threat this freshwater mussel. (AU)

Obtaining monokaryotic and dikaryotic mycelial cultures of two Amazonian strains of Geastrum (Geastraceae, Basidiomycota)

The high diversity of the genus Geastrum and the difficulty of obtaining mycelial cultures impairs the study of the ecophysiology and the exploration of the biotechnological potential of the taxon. In this study, different culture media were tested to obtain mycelial cultures for G. lloydianum and G. subiculosum collected in the Brazilian Amazon. Data on spore germination, and isolation of monokaryotic cultures and in vitro sexual reproduction are presented, as well as a brief morphological description of the cultures obtained. For both species, Potato Dextrose Agar (PDA) was the most promising of the tested culture media. The highest growth in agar culture ever recorded for this genus is reported (4.9 mm per week for G. lloydianum and 7.5 mm for G. subiculosum). In the PDA culture medium, spores germinated after 35-40 days of incubation and the isolation of monokaryotic cultures of the two species, as well as in vitro sexual crosses, were successfully performed. (AU)

Measurement of the Ecological Integrity of Cerrado Streams Using Biological Metrics and the Index of Habitat Integrity.

Generally, aquatic communities reflect the effects of anthropogenic changes such as deforestation or organic pollution. The Cerrado stands among the most threatened ecosystems by human activities in Brazil. In order to evaluate the ecological integrity of the streams in a preserved watershed in the Northern Cerrado biome corresponding to a mosaic of ecosystems in transition to the Amazonia biome in Brazil, biological metrics related to diversity, structure, and sensitivity of aquatic macroinvertebrates were calculated. Sampling included collections along stretches of 200 m of nine streams and measurements of abiotic variables (temperature, electrical conductivity, pH, total dissolved solids, dissolved oxygen, and discharge) and the Index of Habitat Integrity (HII). The values of the abiotic variables and the HII indicated that most of the streams have good ecological integrity, due to high oxygen levels and low concentrations of dissolved solids and electric conductivity. Two streams showed altered HII scores mainly related to small dams for recreational and domestic use, use of Cerrado natural pasture for cattle raising, and spot deforestation in bathing areas. However, this finding is not reflected in the biological metrics that were used. Considering all nine streams, only two showed satisfactory ecological quality (measured by Biological Monitoring Working Party (BMWP), total richness, and EPT (Ephemeroptera, Plecoptera, and Trichoptera) richness), only one of which had a low HII score. These results indicate that punctual measures of abiotic parameters do not reveal the long-term impacts of anthropic activities in these streams, including related fire management of pasture that annually alters the vegetation matrix and may act as a disturbance for the macroinvertebrate communities. Due to this, biomonitoring of low order streams in Cerrado ecosystems of the Northern Central Brazil by different biotic metrics and also physical attributes of the riparian zone such as HII is recommended for the monitoring and control of anthropic impacts on aquatic communities.

Black-fly assemblage distribution patterns in streams in disturbed areas in southern Brazil.

Black flies (Simuliidae) are considered to be pests in rural and in some urban areas in the south of Brazil due to the bites of females. Little information exists on the factors that contribute to Simuliidae distribution in these areas. We sampled 39 streams in the state of Rio Grande do Sul in September 2004 to address ecological aspects. Of the 18 species collected, those that occurred in more than 50% of the streams were: Simulium subnigrum Lutz 1910, Simulium pertinax Kollar 1882, Simulium subpallidum Lutz 1910 and Simulium incrustatum Lutz 1910. Species richness was not influenced by any of the environmental or geographical variables considered, and there was no pattern of species co-occurrence, corroborating the hypothesis of a stochastic distribution of the Simuliidae assemblage. When analyzed individually, only three of seven species with occurrence frequency >30% were related to any of the variables measured. The probabilities of occurrence of Simulium jujuyense Paterson & Shannon 1927 and S. pertinax were higher in streams with high values of water pH and electrical conductivity, whereas the opposite was observed for S. incrustatum. Therefore, due to stochastic distribution, the population studies of Simuliidae are more suitable for predicting the occurrence of species in rural areas than are studies of assemblages.

Species of Oukuriella Epler (Diptera, Chironomidae) inside freshwater sponges in Brazil

Espécies de Oukuriella Epler (Diptera, Chironomidae) no interior de esponjas de água doce no Brasil. Larvas de Oukuriella Epler, 1986 no interior de esponjas de água doce são registradas pela primeira vez no Brasil.

An illustrated key to nymphs of Perlidae (Insecta, Plecoptera) genera in Central Amazonia, Brazil

An illustrated key to nymphs of Perlidae collected in streams of Central Amazonia, Brazil is provided. Three genera are reported for this region: Macrogynoplax Enderlein, Anacroneuria Klapálek and Enderleina Jewett. Additional diagnostic characters are provided for Enderleina nymphs.