The advertisement call of Physalaemus caete Pombal & Madureira, 1997 (Anura: Leptodactylidae: Leiuperinae), an endangered species endemic to Brazil’s northern Atlantic Forest

Foam-nesting frogs of the genus Physalaemus Fitzinger, 1826 have been long known for their diverse acoustic patterns (e.g., Barrio 1965; Bokermann 1966). Of the 49 species, the vocalizations of only three remain unknown to date (see Table 1 of Hepp Pombal 2020): P. caete Pombal Madureira, 1997, P. deimaticus Sazima Caramaschi, 1988, and P. insperatus Cruz, Cassini Caramaschi, 2008. Physalaemus caete is rare and narrowly distributed in Brazil's northern Atlantic Forest (Santos et al. 2016; Bernardo et al. 2017; Haddad et al. 2018), and an explosive breeder (EMS pers. obs.). For those reasons the species is classified in the endangered category of Brazil's red list of threatened species (ICMBio, 2018). Physalaemus caete was described in the late 1990s from the coastal region of the Brazilian state of Alagoas (Passo do Camaragibe) and reported for a second locality in Alagoas (Murici; Pombal Madureira 1997). Recently, the distribution was extended to a third locality (Paulista, state of Pernambuco; Santos et al. 2016). The distribution range of P. caete coincides with the "Pernambuco endemism center", a biogeographic subregion of coastal Atlantic Forest north of the Sao Francisco River (sensu Silva Casteli 2003). Here we describe the advertisement call of the Pernambuco population of P. caete and make comparisons with calls of congeners.