Bioacoustics of Chiasmocleis avilapiresae

Distribution. Known from scattered localities in the Brazilian Amazon basin, south of the Solimões and Amazonas rivers, in the states of Amazonas , Mato Grosso , Pará , and Rondônia ( Fig. 9 ). Natural history. R.I. Crombie’s fieldnotes note that specimens from Nova Colina and Nova Brasília, Rondônia , were collected in primary forest or in clearings/pastures. Specimens occurred near isolated pools in stream flood plain, always on the bank of ponds distant 0.5–1 m from water, under leaves or pieces of bark. Crombie’s notes do not mention calling activity. Specimens from Anapu, Itaituba and from the type locality (Caxiuanã, Pará ) were collected in pitfall traps inside primary forest. Other microhylids collected in the same areas were Chiasmocleis jimi , Ctenophryne geayi , and Hamptophryne boliviana . Chiasmocleis avilapiresae occurs in sympatry with C. bassleri in at least three localities (Espigão do Oeste, Rondônia ; Aripuanã, Mato Grosso and Itaituba, Pará ). In Caxiuanã several specimens of the new species were found in stomachs of Ceratophrys cornuta , and one specimen was regurgitated by a Leptodactylus paraensis (M.A. Ribeiro-Jr, personal communication). A gravid female from the type locality contained approximately 1920 eggs. Advertisement call and tadpoles are unknown.