The genus Xiphorhynchus (Dendrocolaptidae) has 16 known species widely distributed in the Neotropics, especially in the Amazon, which is the center of distribution of several super-species of this genus. The present work is a taxonomic revision of two of these super-species of predominantly Amazonian distribution: X. p ardalotus / ocellatus and X. spixii / elegans. During the work we studied a total of 255 specimens of these two super-species deposited at the Museu Paraense Emílio Goeldi (MPEG), belonging to 10 taxa (pardalotus, caurensis, ocellatus, perplexus, weddellii, brevirostris, spixii, elegans, juruanus and ornatus). For each specimen, the following morphometric characters were measured with a Mutoyo digital pachymeter (in millimeters): lengths of (1) wing, (2) tail, (3) tarsus, (4) bill, (5) thickness and (6) width of the bill. Nine plumage characters were also incorporated into the analyses (length, height and width of pectoral, dorsal and cephalic spots, respectively). A multivariate analysis (PCA) of the studied taxa was performed based only on the characters that varied significantly among them. It was thus possible to determine that the super-species X. pardalotus / ocellatus is composed of the following valid taxa, which can be considered phylum-genetic species: pardalotus, ocellatus, weddellii and chunchotambo. In the case of X.spixii / elegans, it was possible to diagnose the following phylogenetic species: spixii, elegans, juruanus and ornatus. These results demonstrate the importance of taxonomic revisions for the recognition of new valid species and the consequent improvement of knowledge about biodiversity.
|
