RESUMO
Some groups of invertebrates from intermittent wetlands produce dormant stages in response to environmental fluctuations. Dormancy is a strategy to survive such fluctuations and to persist in extreme aquatic habitats, such as temporary habitats. We investigated the hatching responses of invertebrate dormant stages across different depths of sediment in intermittent ponds. Our hypotheses were: (1) the richness and abundance of invertebrate hatchlings decrease as the depth of the sediment column increases, and (2) the composition of invertebrate hatchlings varies over the wetland sediment depth. Four intermittent ponds were sampled in southern Brazil. One sediment column of 30 cm depth was collected in each pond and stratified into 1 cm thick slices for analysis of the dormant stages. A total of 1,931 hatchlings distributed among 31 taxa were collected from the sediment columns over the experiment. The total richness and abundance of hatchlings (after bdelloid taxa exclusion) were negatively related with the sediment depth. The composition of aquatic invertebrates varied among the different strata over the sediment depth. As intermittent wetlands are ecosystems extremely susceptible to climate variations, the results help to understand the resilience of aquatic resistant communities from different sediment strata after drought events. Supplementary Information: The online version contains supplementary material available at 10.1007/s13157-023-01675-6.
RESUMO
Abstract We recorded for the first time the lesser dung fly Maculantrops hirtipes (Macquart, 1844) from Brazil, state of Rio Grande do Sul. Twenty-five specimens were reared from the dung of Myocastor coypus (Molina, 1782), this is the first record of the feeding substrate for the genus Maculantrops and the second only for the Archiborborinae. In addition, we describe the puparium, provide an updated distribution map and additional photographs of the species.
Resumo Registramos pela primeira vez a mosca-do-esterco Maculantrops hirtipes (Macquart, 1844) no Brasil, no estado do Rio Grande do Sul. Vinte e cinco espécimes foram obtidos em amostras fecais de Myocastor coypus (Molina, 1782). Este é o primeiro registro do substrato alimentar para o gênero Maculantrops e o segundo apenas para subfamília Archiborborinae. Além disso, descrevemos o pupário, fornecemos um mapa de distribuição atualizado e fotografias adicionais da espécie.