ABSTRACT
Abstract An inventory of Odonata was carried out in the southern half of the state of Rio Grande do Sul, Brazil, in the Pampa biome. Originally, this biogeographical region was covered mostly by open fields and grassland, with sections of higher vegetation surrounding water bodies and rocky hills. Today the landscape is fragmented due to agricultural activities, mainly cattle farming, rice crops and forest plantations. Our survey was conducted in three municipalities from this region, between March 2015 and April 2016. Aiming at a general overview of the species composition, our sampling sites were selected on a wide basis, including lakes, bogs, temporary water bodies, small streams and river sections. Eighty two species of Odonata were collected comprising 40 genera and seven families. The dominant families were Libellulidae (56,1%), Coenagrionidae (24,5%) and Aeshnidae (7,3%). We found a diverse odonate assemblage, adding 19 new species records for the state of Rio Grande do Sul.
Resumo Um inventário de Odonata foi desenvolvido na metade Sul do estado do Rio Grande do Sul, Brasil, no Bioma Pampa. Originalmente, esta região biogeográfica era coberta principalmente por campos abertos e pastagens, com seções de vegetação mais alta nas imediações de corpos d'água e elevações rochosas. Atualmente a paisagem se encontra fragmentada devido a atividade agrícola, entre as principais, a criação de gado, cultivo de arroz e silvicultura. A pesquisa foi desenvolvida em três municípios da região, entre Março de 2015 e Abril de 2016. Buscando uma visão geral da composição de espécies, os locais de amostragem selecionados incluíram lagos, banhados, corpos d'água temporários e seções de rio. Oitenta e duas espécies foram coletadas compreendendo 40 gêneros e 7 famílias. As famílias dominantes foram Libellulidae (55,1%), Coenagrionidae (24,5%) e Aeshnidae (7,3%). Nós encontramos uma grande diversidade nas comunidades de Odonata, adicionando 19 novos registros de espécies para o estado do Rio Grande do Sul.
ABSTRACT
Abstract A survey of Odonata was carried out in the National Forest FLONA - SFP, Northeastern region of the Rio Grande do Sul state, Brazil. This conservation unit is mainly covered by Mixed Ombrophilous Forest (MOF), a subtype of Atlantic Forest biome, being also areas covered in planted Pinus, planted Araucaria and open fields. Our sampling efforts were conducted in thirty aquatic environments inside this reserve during the period between January 2014 and November 2014. The sampling sites were selected randomly, comprehending lakes, bogs, small streams and river sections, all inserted in the four vegetation types occurring in the reserve. Fortysix species of Odonata were collected and grouped into 23 genera and seven families. The dominant families were Coenagrionidae (32%), Libellulidae (32%), Aeshnidae (12%), and, Calopterygidae and Lestidae (9%). As expected, the findings revealed the presence of a highly diverse Odonate assemblage, mainly represented by generalist species in the most human disturbed sectors (Pinus and Open fields) and some specialist species in the pristine forest. Two species were registered for the first time in the state of Rio Grande do Sul, Brazil: Libellula herculea Karsch, 1889 (Libellulidae) and Heteragrion luizfelipei Machado, 2006 (Heteragrionidae).
Resumo Uma pesquisa de Odonatas foi desenvolvida na Floresta Nacional de São Francisco de Paula (FLONA - SFP), Rio Grande do Sul, Brasil. Esta unidade de conservação é, em grande parte, coberta por Floresta Ombrófila Mista, um subtipo de floresta do Bioma Mata Atlântica, sendo também áreas cobertas com plantação de Pinus, Araucaria, além de áreas de campo aberto. Nossos esforços de coleta abrangeram 30 ambientes aquáticos dentro da reserva, no período de Janeiro de 2014 e Novembro de 2014. Os locais de coleta foram selecionados aleatoriamente, compreendendo lagos, banhados, pequenos arroios e seções de rio, todos inseridos nos quatro tipos de vegetação ocorrentes na reserva. Foram coletadas 46 espécies de Odonata, agrupadas em 23 gêneros e sete famílias. As famílias dominantes foram Coenagrionidae (32%), Libellulidae (32%), Aeshnidae (12%), e, Calopterygidae e Lestidae (9%). Como esperado, os resultados revelaram a presença de uma alta diversidade de Odonata, em sua maioria generalistas, encontrados nos setores mais impactados pelo homem (Pinus e Campos abertos) e algumas espécies especialistas na floresta primária. Duas espécies foram registradas pela primeira vez no estado do Rio Grande do Sul, Brasil: Libellula herculea Karsch, 1889 (Libellulidae) e Heteragrion luizfelipei Machado, 2006 (Heteragrionidae).
ABSTRACT
We present a key to the Costa Rican species of Pseudostigmatidae, comprising three genera with the following species: Megaloprepus caerulatus, Mecistogaster linearis, M. modesta, M. ornata and Pseudostigma aberrans. Pseudostigma accedens, which may occur in the region, is also included. For each species we give a brief account of morphology, phenology and life zone preferences, including distributional maps based on more than 270 records. These are not all of the known specimens from the area, but a high enough number to give a relatively good picture of the distribution and status of the species. We found M. caerulatus to be active during the first half of the year in seasonal, tropical semi-dry lowland forest and tropical moist forest at mid-elevation, but like M. linearis, M. caerulatus was active all year round in non-seasonal, tropical wet lowland forest and tropical moist forest at mid-elevation. Mecistogaster modesta also flew year round in non-seasonal, tropical wet lowland forest and tropical moist evergreen forest at mid-elevation, and likewise in seasonal and non-seasonal, tropical premontane moist forest. Only a few findings, however, have been made of M. modesta in seasonal, tropical semi-dry deciduous forest and seasonal, tropical moist evergreen forest. Mecistogaster ornata was missing entirely from non-seasonal, tropical wet lowland forest and non-seasonal, tropical moist forest at mid-elevation, while this species was active year round in seasonal, tropical dry lowland forest and tropical semi-dry forest, as well as in seasonal, tropical moist evergreen forest and tropical premontane moist forest, both at mid-elevation. Pseudostigma aberrans has so far been found too few times in Costa Rica for any indication of flight time preference.