First record of Dero (Aulophorus) bimagnasetus Harman (Oligochaeta) from Brazil and habitat characteristics

Annelid worms represent a significant part of freshwater benthic communities worldwide and Oligochaeta is a particularly species-rich group. Dero (A) bimagnasetus (Naididae) previously found and described from a small marsh in Surinam in 1974, has now been found for the first time in Barra Lake, MG, Brazil. Due to the scarce biological data and absence of ecological information in the literature regarding this species we are presenting morphological information on the specimens obtained and the physical and chemical characteristics of the habitat they were found. This species occurred only in the littoral zone of Barra Lake, in muddy, low oxygen, low conductivity and low organic matter sediment. The four individuals collected ranged 3.17-4.15 mm total length; 0.25 - 0.26 mm body width and 0.16-0.21 mm3 total volume. Considering the present anthropic pressures on freshwater biota and fast biodiversity losses worldwide it is now recognized that attention must be paid to low abundance species and the urgency for preservation of their habitats

First record of Dero (Aulophorus) bimagnasetus Harman (Oligochaeta) from Brazil and habitat characteristics

Annelid worms represent a significant part of freshwater benthic communities worldwide and Oligochaeta is a particularly species-rich group. Dero (A) bimagnasetus (Naididae) previously found and described from a small marsh in Surinam in 1974, has now been found for the first time in Barra Lake, MG, Brazil. Due to the scarce biological data and absence of ecological information in the literature regarding this species we are presenting morphological information on the specimens obtained and the physical and chemical characteristics of the habitat they were found. This species occurred only in the littoral zone of Barra Lake, in muddy, low oxygen, low conductivity and low organic matter sediment. The four individuals collected ranged 3.17-4.15 mm total length; 0.25 - 0.26 mm body width and 0.16-0.21 mm3 total volume. Considering the present anthropic pressures on freshwater biota and fast biodiversity losses worldwide it is now recognized that attention must be paid to low abundance species and the urgency for preservation of their habitats

Acute and Chronic Effects of Three Pharmaceutical Drugs on the Tropical Freshwater Cladoceran Ceriodaphnia silvestrii

Among emerging contaminants, pharmaceuticals are one of the most relevant groups of substances found in aquatic environment, due to their universal use, specific physical-chemical properties, and mode of action in aquatic organisms at low concentrations. Considering the magnitude of concentrations and the considerable small amount of information about their potential ecotoxicological effects on wildlife (especially towards organisms from tropical areas), the present study intended to assess the acute and chronic effects of three pharmaceuticals (the analgesic acetaminophen, the anti-inflammatory diclofenac, and the antihypertensive propranolol) in the tropical crustacean species Ceriodaphnia silvestrii. Results of acute exposures showed a considerable variation in toxicity among pharmaceuticals: acetaminophen (EC50 = 40.3 mg L−1) < diclofenac (EC50 = 37.9 mg L−1) < propranolol (EC50 = 3.17 mg L−1), C. silvestrii being more sensitive to the drug propranolol. Data of chronic toxicity tests showed the occurrence of reproductive adverse effects, but also stimulatory phenomena. Propranolol caused a significant increase in fecundity for the concentrations up to 0.0313 mg L−1, and the rate of population increase was significantly augmented from the lower concentration tested. Considering these results and the wide distribution of C. silvestrii in tropical regions, we suggest the use of this species to be used as test organism in ecotoxicity assays performed in such areas, especially for biomonitoring and/or the determination of effects of pharmaceutical drugs. © 2018, Springer International Publishing AG, part of Springer Nature.Acknowledgments We are grateful to the Brazilian Research Council (CNPq) for the financial support provided for this research project (No. 142131/2010-5). Bruno Nunes was hired under the program Investigador FCT, co-funded by the Human Potential Operational Program (National Strategic Reference Framework 2007–2013) and European Social Fund (EU). Sara Antunes was funded by a post-doctoral fellowship (SFRH/BPD/109951/2015) by Fundação para a Ciência e Tecnologia (Government of Portugal)