ECUADOR: No specific locality, WCAB 35452-3; "Napo-Pastaza," USNM 166571. _Napo_: Avila, UMMZ 92093; south slope Cordillera del Due, KU 123170; Lago Agrio, KU 125961-2 (skeletons), 126611-44, UMMZ 129326 (2); Limon Cocha, Rio Napo, KU 99210-6, UIMNH 63087-9, 63098, 63106-9, 63118-9, 64802-4, 64858, 87998-9, 88001-30, 88437-8, 88580, 88604-5, 89852-97, 89999-90000; Loreto, CAS-SU 11439, WCAB 36526; Puerto Libre, Rio Aguarico, KU 123190-1; Puerto Napo, UIMNH 55818-20; Rio Cotapino, UMMZ 92094; Rio Napo, UMMZ 92078; Santa Cecilia, AUM 8099, 8102, 8113-5, 8127-9, 8131, 8137, 8139-46, 8148, KU 105210-20, 109509-11, 111971, 122964-87, 123169, 126645. _Pastaza_: Canelos, BMNH 1947.2.13.42, KU 120915; Rio Alpayacu, UMMZ 92079; Rio Arajuno, USNM 166560-2, WCAB 40176; Rio Oglan, USNM 16655203, 166558; Rio Rutuno, USNM 166559; Rio Shilcayacu, below Puyo, USNM 166557; Rio Villano, USNM 166551. FRENCH GUIANA: No specific locality, MNHN 4629. _Inini_: Lunier River, MNHN 98/217. GUYANA: _Mazaruni-Potaro_: Kartabo, AMNH 70967-8, 70972, 70976. _Rupununi_: Shudi-kar-wau, AMNH 49255. _West Demerara_: Demerara Falls, BMNH 72.10.16.23, 72.10.16.37-8. PERU: _Loreto_: Estiron, Rio Ampiyacu, MZUSP 31033-4; Pebas, CAS-SU 3158, 3160; Roaboya, AMNH 43064. SURINAM: No specific locality, MCZ 2036, RMNH 11468. _Marowijne_: Camp 3, RMNH 13045-6; Wane Creek North, RMNH 11469-70. _Saramacca_: Right Coppename River, RMNH 11467. _Osteocephalus pearsoni_ BOLIVIA: _El Beni_: upper Rio Beni, below mouth of Rio Mapiri, MCZ 15565, UMMZ 57548, 67464-5; Rurrenbaque, UMMZ 57533. PERU: _Pasco_: Yaupi, KU 136312. _Osteocephalus taurinus_ BOLIVIA: _El Beni_: Ivon, BMNH 1967.2040; Reyes, UMMZ 57532. _La Paz_: San Ernesto, Mapiri District, BMNH 1901.8.2.54. _Santa Cruz_: Buenavista, AMNH 33951-2, 33958, BMNH 1927.8.1.19, 1927.8.1.118, FMNH 27091, UMMZ 63319-21, 63959(2), 63961(2), 66566(2), 66567, 66568(2), 66569 (2), 66570, 66571(2), 66575-6, 68196; Rio Mamore, 2 km N Boca Chapare, AMNH 79324; Sara, CM 3840-1; Surutu, CM 3814-5.