Comunidade de anfíbios anuros na Mata Atlântica da Reserva Natural Salto Morato, Paraná, sul do Brasil: diversidade, distribuição altitudinal e conservação

Abstract

This study addresses the composition and spatial variation of amphibians anurans community along an altitudinal gradient from 25 up to 918 m above sea level (m asl), in the Salto Morato Nature Reserve (RNSM), Paraná, southern Brazil. To collect the frogs the methodology used was transects with active search. A total of 41 frog species was recorded in the Salto Morato in this study. The most representative family was Hylidae (15 species, 36.6% of the total), followed by Brachycephalidae (eight species, 19.5%) and Bufonidae and Leptodactylidae (five species each, 12.2% each). Considering other previous studies in the RNSM, the data indicate that currently 54 frog species are recorded as occurring in the area, and most of these, are endemic to the Atlantic Forest (94.4% of total). This species richness in Salto Morato, corresponding to 36.5% of the 148 frog species recorded to occur in the state of Paraná, through the survey of studies conducted in the state, by this thesis. The frogs Ischnocnema sambaqui, Cycloramphus mirandaribeiroi and Brachycephalus tridactylus are endemic to the state of Paraná, the latter being a micro-endemic species to the RNSM, found only in the highest portion of the Reserve (800-930 m asl). None species of frog recorded in RNSM consists listed as endangered on the Red List (state, Brazilian and world). However, four frog species (Ischnocnema sambaqui, Cycloramphus mirandaribeiroi, Cycloramphus asper, Gastrotheca microdiscus and Hylodes heyeri) are categorized as "Data Deficient" (DD). The empirical richness of frogs showed a linear decrease with increased altitude in the RNSM and the greatest richness were recorded in lower altitudes up to 100 m asl (n = 24), decreasing to the region from the summit of the RNSM in 918 m asl (n = 13), especially with a considerable decline between 101-200 m asl (n = 14) and an increase in richness between 501-600 m asl (n = 20). The altitude (reflecting environmental parameters), the area, the ecotones (between different vegetation formations) and the Rapoport effect explained the richness and composition of frog species along the altitudinal gradient in the RNSM. On the other hand, the Middle Domain Effect did not explain the richness of frog species in the Reserve, that is, there was not greater species richness at intermediate altitudes by increasing the overlap of the distribution of the frog species. The high richness of frogs in the RNSM, combined with the high recorded endemic rates and also the presence of the populations of the species for which the currently available data did not allow define their conservation status, reinforces the importance of RNSM for the conservation and for the maintenance of frog populations and communities of the Atlantic Forest biome