Rotifers in an area of the Pantanal de Marimbus, Chapada Diamantina, Bahia, Brazil: New occurrences for the state of Bahia

Abstract

Rotifers are predominant micrometazoans in continental aquatic ecosystems, in several biotopes, whether in plankton, periphyton and even in the hyporheic zone. The present study aimed to inventory the Rotifera assemblage in an area of the Pantanal de Marimbus, Baiano, in Chapada Diamantina, state of Bahia. Samples were collected in two periods: “high waters” and “low waters”. In each period, the samplings were carried out in plankton and periphyton (30 samples, each), totaling 60 samples per period. Were recorded 48 taxa infrageneric distributed in 13 families and 20 genera, with 11 taxa considered new occurrences for the state of Bahia. The Lecanidae family was the most representative in terms of richness (21 taxa), abundance and frequency of occurrence (%). Brachionidae, Trichocercidae, Lepadellidae and Synchaetidae also stood out in some of these mentioned attributes. The most expressive richness of Rotifera was observed in the planktonic biotope (44 taxa) when compared to the periphyton (37 taxa), and in the “high water” period (37 taxa) when compared to the “low water” period (34 taxa). The wetland of the Pantanal of Marimbus exhibits a great richness of Rotifera species, predominating non-planktonic forms, which may be due to the presence of aquatic macrophytes promoting the environmental heterogeneity and diversity of rotifers in this peculiar environment. Our results expand the known distribution for Rotifera species in Brazil and contribute to the knowledge of these micrometazoans in the state of Bahia, especially in the Pantanal de Marimbus with the first record of this group.