Synallaxis omissa E. J. O. HARTERT 1901
Creators: name: Stopiglia, Renata
name: Barbosa, Waleska
name: Ferreira, Mateus
name: Raposo, Marcos A
name: Dubois, Alain
name: Harvey, Michael G
name: Kirwan, Guy M
name: Forcato, Giovanna
name: Bockmann, Flavio A
name: Ribas, Camila C
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Aves
Passeriformes
Furnariidae
Synallaxis
Synallaxis omissa

description: SYNALLAXIS OMISSA E.J.O. HARTERT, 1901
Synallaxis omissa E.J.O. Hartert, 1901: 71
(holotype AMNH 523598, adult female from Pará, Brazil, examined by us; see Remarks 4, 5 and 6 for comments).
Diagnosis: Synallaxis omissa differs from S. rutilans, S. amazonica, S. caquetensis and S. dissors in having the forehead, supercilium and face Vandyke brown (221) without any trace of rufous.
Description: Throat sepia (119); breast and abdomen hair-brown (119a) with or without cinnamon (39) elements; flanks olive brown (28) varying individually to hair-brown (119a); rectrices sepia (119); back hairbrown (119a) with variable traces of amber (36); crown, forehead, supercilium and face Vandyke brown (221); wing-coverts amber (36); remiges Vandyke brown (121); bill length 12.3–15.1 mm; bill depth 4.0– 5.1 mm; wing length 54.9–64.9 mm; tail length 58.0– 74.5 mm, with ten rectrices (see Tables 7, 8).
Distribution: Synallaxis omissa is entirely allopatric with S. rutilans, S. amazonica, S. caquetensis and S. dissors, being restricted to the area east of the right bank of the Tocantins River, in south-eastern Pará and northern and western Maranhão, Brazil. The geographic range of the species is restricted to the Belém AE [as defined by Haffer (1969)] and all records of S. rutilans in the state Maranhão are attributable to S. omissa. Distribution represented in Figures 1 and 4 by yellow colour of the Belém AE.
Remarks 4: According to E.J.O. Hartert (1901), the holotype of Synallaxis omissa, AMNH 523598, an adult female, was collected by Joseph Beal Steere (1842–1940), on 19 July 1897. LeCroy & Sloss (2000) highlighted that the correct year of collection was 1879 [not 1897, as reported by E.J.O. Hartert (1901)].
Remarks 5: The original description of S. omissa cited the type locality as Pará, Brazil (E.J.O. Hartert, 1901). Subsequently, Paynter & Traylor (1991: 66) considered this to be more precisely defined as ‘Belém’, and designated the coordinates 0127/4829 (USBGN) for the precise location. Restriction of the type locality of S. omissa to Belém, Pará, was corroborated by Papavero et al. (2008: 133) and is consistent with the species distribution east of the right bank of the Tocantins River based on the specimens we studied.
Remarks 6: Peters (1951: 91) stated that ‘The majority of the specimens of this race lack any trace of rufus on the head and underparts; occasional specimens however are coloured exactly like S. r. rutilans ’, and in fact, as previously reported, the underparts of S. rutilans and S. omissa can appear similar in respect of those specimens of the latter with cinnamon (39) colour on the breast and abdomen. However, S. omissa is diagnosed by the plumage of the head and contra Peters (1951), among all of the 317 specimens analysed by us (including those in the Museum of Comparative Zoology, where Peters was curator while preparing his Check-list of birds of the world in 1931–52), we have not located any individual of S. omissa with the coloration of S. rutilans (or S. dissors and S. caquetensis) on the head. In other words, none of the specimens showed any trace of amber (36) or cinnamon (39) on the head and face, whereas all individuals of S. rutilans, S. dissors and S. caquetensis analysed by us were well marked in this respect. It is important to note that S. omissa, although considered a subspecies of S. rutilans, has been distinguished to some extent as a unique biological entity by use of a unique vernacular name. Whereas the English name of all other taxa within the S. rutilans group is ruddy spinetail, sooty spinetail was used for S. omissa by del Hoyo & Collar (2016).
description: 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 81, DOI: 10.1093/zoolinnean/zlab076, http://zenodo.org/record/6530667