SYNALLAXIS CAQUETENSIS CHAPMAN, 1914 Synallaxis rutilans caquetensis Chapman, 1914: 621 (holotype AMNH 116376, an adult male from Florência, Caquetá, Colombia, examined by us). Synallaxis rutilans confinis Zimmer, 1935: 4 (holotype AMNH 312067, an adult male from Igarapé Cacao Pereira, right bank of the Negro River, Brazil, examined by us). Diagnosis: Synallaxis caquetensis differs from S. omissa in having the forehead, supercilium and face amber (36). Compared to S. dissors, S. caquetensis differs in having the upperparts chestnut (32) and, sometimes, the crown chestnut (32) or amber (36). Synallaxis caquetensis cannot be diagnosed morphologically in relation to S.rutilans and S.amazonica, because the rufous pattern of S. caquetensis is replicated to a greater or lesser extent in populations of S. rutilans and S. amazonica. Description: Throat sepia (119); breast amber (36), varying individually between chestnut (32) and robin rufous (340); abdomen and flanks olive brown (28), varying individually with elements of raw umber (123) as the secondary colour; rectrices sepia (119); back chestnut (32), varying individually between olive brown (28) and raw umber (223); crown varies individually between olive brown (28), amber (36) and chestnut (32); forehead, supercilium and face amber (36), varying individually to chestnut (32); wing-coverts chestnut (32), varying individually to amber (36); remiges Vandyke brown (121), varying individually to Vandyke brown (221); bill length 11.9–14.2 mm; bill depth 4.0– 4.8 mm; wing length 54.3– 60.8 mm; tail length 52.0–61.0 mm, with ten rectrices (see Tables 7, 8). Distribution: North-east Peru, eastern Ecuador, south-east Colombia and north-west Brazil, from the right bank of the Negro River to the left bank of the Amazonas/Solimões. The distribution of Synallaxis caquetensis is represented in Figures 1 and 4 by the red colour of Napo AE.

Published as part of Stopiglia, Renata, Barbosa, Waleska, Ferreira, Mateus, Raposo, Marcos A, Dubois, Alain, Harvey, Michael G, Kirwan, Guy M, Forcato, Giovanna, Bockmann, Flavio A & Ribas, Camila C, 2022, Taxonomic challenges posed by discordant evolutionary scenarios supported by molecular and morphological data in the Amazonian Synallaxis rutilans group (Aves: Furnariidae), pp. 65-87 in Zoological Journal of the Linnean Society 195 (1) on page 82, DOI: 10.1093/zoolinnean/zlab076, http://zenodo.org/record/6530667