Physalaemus signifer species group

Several species in this group have pulsed call ( P. angrensis, P. atlanticus, P. bokermanni, P. crombiei, P. irroratus, P. moreirae, P. nanus, and P. obtectus) and show nonlinear regimes (acoustic features more complex than usually expected for simple oscillators; see Material and Methods above) such as subharmonics, deterministic chaos, and frequency jumps ( P. angrensis, P. atlanticus, P. bokermanni, P. camacan, P. crombiei, P. irroratus, P. moreirae, P. nanus, P. obtectus, P. signifer, and P. spiniger). All species, except P. bokermanni, have at least one call with structures long enough to make them sound, to the human ear, as nasal-like whines with high timbre; due to the energy concentrated in higher and dense harmonics.