Abstract
The family Hylodidae contains 42 species allocated in the genera Crossodactylus (11 species),Hylodes (24 species) and Megaelosia (7 species). These species inhabit streams with small waterfalls in the Brazilian Atlantic Forest, occurring from Alagoas to Rio Grande do Sul States in Brazil, reaching Misiones, Argentina. Due to adaptations to waterfall environments, a plesiomorphic morpholog…