An update of the geographical distribution of Hylodes pipilans (Canedo & Pombal, 2007), an endemic Torrent frog of the Brazilian Atlantic Forest, with comments on its conservation

The Brazilian Atlantic Forest (BAF) is hotspot for conservation priorities due to the high concentration and maintenance of biodiversity, comprising more than 600 species of amphibians, of which 88% are endemic to this biome. Many of these species are under some level of threat, especially those with restricted distributions to mountainous regions. Hylodes is the most speciose genus within Hylodidae, housing 26 recognized species of the diurnal frogs related to streams of forest massifs in the BAF. Hylodes pipilans is endemic to the state of Rio de Janeiro, considered restricted to the Serra do Orgaos mountains. Here, we updated its records based on fieldwork, bioacoustics analysis, and museum data, enhancing the species distribution comprehension. Additionally, we evaluate its occurrence inside of protected areas, updating information to subsidize conservation actions for this poorly known Torrent frog. We recorded individuals of H. pipilans in Parque Nacional da Serra dos Orgaos and Reserva Biologica do Tingua. The vocalizations analyzed were compatible with the bioacoustics traits of H. pipilans. Its distribution covers part of six municipalities in the Serra dos Orgaos Mountain range, northern portion of Serra do Mar, between 245 and 814 meters above sea level. The new record to the Reserva Biologica do Tingua is the species southernmost record. Despite the previous assessment on the conservation status of H. pipilans suggest as a least concern species, little is known about its occurrence extension, occupancy area, population trends, and ecological information. Thus, the present study is particularly important to enhance the understanding of altitudinal and geographic distribution range for H. pipilans. These will assist in the species conservation status reassessment.