Xiphorhynchus vicinalis Todd, 1948

Raposo, Marcos A., Kirwan, Guy M., Fonseca, Odirlei, Selvatti, Alexandre Pedro, Höfling, Elizabeth & Stopiglia, Renata, 2025, Towards a more coherent taxonomy for the woodcreepers Xiphorhynchus guttatus and X. guttatoides (Aves: Passeriformes: Dendrocolaptidae), Zootaxa 5683 (4), pp. 492-512 : 506-507

Xiphorhynchus vicinalis Todd, 1948

Type material: The holotype of Xiphorhynchus vicinalis Todd, 1948 , is held at the Carnegie Museum of Natural History, Pittsburgh, CM P78061, an adult male, from Apacy, Rio Tapajós, Brazil, collected on 30 April 1920 by Samuel M. Klages ( Todd 1948).

Diagnosis: Like Xiphorhynchus eytoni , X. vicinalis differs from most species in the X. guttatus group by having the throat streaking generally whitish, the bill darker (blackish not silvery gray), and the dark cap more clear-cut. X. vicinalis differs from X. eytoni by morphometrics (see below) and by having overall buffier underparts, tinged clay-coloured ventrally, and, on average, heavier streaking on both surfaces.

Variation: An ecological division was suggested by the observations of Snethlage (1913) who reported X. vicinalis as being found in lowland usually flooded forests (e.g., the Rios Andirá, Ramos and Limão), and X. guttatoides in higher areas of drier forest, for example the Serra dos Parintins. Two specimens from Faro (on the Pará / Amazonas border) were also attributed, by Todd (1948), to X. vicinalis . Despite this locality being north of the Rio Amazonas, given the lack of precise label data, Zimmer (1934) left open the possibility that these specimens had been taken from the right (i.e., south) bank of the river. Hellmayr (1910) and Cory & Hellmayr (1925) suggested the presence of intermediates between X. guttatoides and X. vicinalis among those specimens collected on the right bank of the upper Rio Madeira (Salto Theotonio, Calama, Aliança) and in northern Mato Grosso (on the Rio Roosevelt), which had the bill colour and shape of X. guttatoides , despite being somewhat darker in plumage.

Morphometrics: Males of X. vicinalis have mean values larger than females, especially in wing and tail lengths. Culmen, wing and tail lengths of X. vicinalis are significantly longer than X. polystictus , and wing length is also significantly longer than X. guttatoides (see Tables 2 and 3).

Range: Confined to Brazil, where it occurs in the Rondônia and Tapajós areas of endemism, in the Madeira- Xingu interfluvium (see Figs. 3‒4 ).

Figures

FIGURE 3. Map depicting the distribution of plumage analyses: black circles, morphotype 1, green area, Atlantic Forest area of endemism (AE); white triangles, morphotype 2, purple area, Guiana AE; black diamonds, morphotype 3, red and grey areas, Napo-Inambari AE and Cerrado Biome, respectively; and grey squares, morphotype 4, yellow and blue AEs, Xingu-Belém and Rondônia-Tapajós, respectively, and grey and light green areas, Cerrado and Caatinga Biomes, respectively.

FIGURE 4. Map depicting results of taxognosis analyses and the taxonomic proposal: black circles, Xiphorhynchus guttatus; white triangles, X. polystictus; black diamonds, X. guttatoides; white stars, X. vicinalis; and grey squares, X. eytoni.