The effect of different stream environmental preservation levels, in 1st to 4th orders, over the richness, abundance, similarity in the composition and the potential of Baetidae (Ephemeroptera) species as bioindicators were investigated in a Cerrado region located in the state of Mato Grosso, Brazil. A total of twenty species/morphospecies were catalogued from the 1752 samples of nymphs, resulting in a new record for two species in Brazil. Values of Habitat Integrity Index (HII) were categorized among damaged, modified, and preserved environments. Species richness was different between sites, being greater in disturbed habitats. Total abundance was higher among preserved and altered environments, and differed significantly from the degraded areas. The NMDS analysis indicates that, in preserved and modified sites, the similarity in the composition of species differs from degraded areas. Four species showed a positive relationship with increasing values of HII. Baetidae showed environmental indicator species with different levels of preservation, with Zelusia principalis Lugo-Ortiz & McCafferty, 1998 and Baetodes sp. being indicators of preserved environments and Aturbina nigra Salles, Boldrini & Shimano, 2011, Callibaetis sp. 2, Camelobaetidius aff. janae, Paracloeodes binodulus Lugo-Ortiz & McCafferty, 1996 and Waltzoyphius roberti Thomas & Peru, 2002 as indicators of modified environments. The knowledge on the ecology of species advances in terms of providing subsidies for the biomonitoring of basins and the use of indicator species.
Abundance; richness; similarity; Index of Habitat Integrity; indicator species