Diversity and distribution of the annual killifishes of the family rivulidae in the Ribeira Valley and in the South Coast of São Paulo: a contribution for the conservation of semelparous species in a hotspot of the Southeastern Brazil

Abstract

Although freshwater and transitional systems have been found as the most threatened environments in the world due to anthropogenic actions (e.g., disorderly occupation, effluent discharges from agriculture and deforestation), there is still a large gap that needs to be addressed, with data that promote the conservation of areas of occurrence of species with restricted taxonomic and geographic resolution. In this context, the present study aims to diagnose the species belonging to the Rivulidae family (annual killifishes) in the Ribeira Valley and in the South Coast of São Paulo. It is intended to map the occurrence sites, based on historical records and field work, to characterize the occupied habitats and to evaluate the conservation status of the species, producing predictive graphs of habitat preference of the observed taxa, as well as obtaining their vulnerability in face to different pressure vectors. The results obtained could contribute directly to some of the goals proposed by the National Plan for the Conservation of Rivulid fish (PAN Rivulídeos), in the scope of research on the biology, behavior and distribution of the gruop, besides establishing a network of cooperation between researchers of entities such as the Museum of Zoology of the University of São Paulo (MZUSP) and two units of the State University of São Paulo (UNESP). It will be possible to fill an information gap of about ten years regarding the occurrence of Rivulidae species in the southeast region of São Paulo, confirming or not the occurrence of taxa previously observed and/or considered as having a potential occurrence in the area, with important consequences for its conservation. Estimates of abundance as well as assessments of the conservation status of the species recorded may contribute to discussions about the protection of rivulids and their occurrence sites in the area under consideration.