Daniel Philippe
Well-known member
Azuaje-Rodríguez R.A., Weckstein J.D., Dispoto J.H., Patel S., Cacioppo J.A., Bates J.M., Marques Silva S. & Aleixo A., in press. Molecular systematics of the Amazonian endemic genus Hylexetastes (Aves: Dendrocolaptidae): taxonomic and conservation implications.
Abstract
Hylexetastes woodcreepers are endemic to the Terra Firme forests of the Amazon basin. Currently, most taxonomic sources recognize two species of Hylexetastes (H. perrotti and H. stresemanni), each divided into three subspecies. Some authors maintain that the subspecies H. perrotti be elevated to full species status. In particular, H. p. brigidai is endemic to the eastern Amazon, the second Amazonian area of endemism (Xingu) most affected by deforestation and habitat degradation. Consequently, the taxonomic status of H. p. brigidai is of special concern for conservation. Thus far, only morphological characters have been evaluated for the taxonomic delimitation of species and subspecies of Hylexetastes. We present a molecular phylogenetic analysis of all subspecies to help delimit Hylexetastes interspecific limits. Fragments of two mitochondrial (Cytb and ND2) and three nuclear genes (FGB5, G3PDH and MUSK) from 57 Hylexetastes specimens were sequenced. An ecological niche model was estimated to describe more accurately the potential distributions of taxa and to evaluate their vulnerability to ongoing deforestation. Phylogenetic analyses support the paraphyly of the polytypic H. perrotti as currently delimited and the elevation of H. p. uniformis to full species rank, as well as the presence of three Evolutionary Significant Units (ESUs) within this newly delimited species, including one grouping all H. p. brigidai specimens. Alternatively, under lineage-based species concepts, our results support at least five evolutionary species in Hylexetastes: H. stresemanni; H. undulatus; H. perrotii; H. uniformis; and H. brigidai. Each of these taxa and ESUs are distributed in different interfluvial areas of the Amazon basin, which have different degrees of disturbance. Because they occupy the most heavily impacted region among all Hylexetastes ESUs, regular assessments of the conservation statuses of H. p. brigidai and both H. uniformis ESUs are paramount.
Abstract
Hylexetastes woodcreepers are endemic to the Terra Firme forests of the Amazon basin. Currently, most taxonomic sources recognize two species of Hylexetastes (H. perrotti and H. stresemanni), each divided into three subspecies. Some authors maintain that the subspecies H. perrotti be elevated to full species status. In particular, H. p. brigidai is endemic to the eastern Amazon, the second Amazonian area of endemism (Xingu) most affected by deforestation and habitat degradation. Consequently, the taxonomic status of H. p. brigidai is of special concern for conservation. Thus far, only morphological characters have been evaluated for the taxonomic delimitation of species and subspecies of Hylexetastes. We present a molecular phylogenetic analysis of all subspecies to help delimit Hylexetastes interspecific limits. Fragments of two mitochondrial (Cytb and ND2) and three nuclear genes (FGB5, G3PDH and MUSK) from 57 Hylexetastes specimens were sequenced. An ecological niche model was estimated to describe more accurately the potential distributions of taxa and to evaluate their vulnerability to ongoing deforestation. Phylogenetic analyses support the paraphyly of the polytypic H. perrotti as currently delimited and the elevation of H. p. uniformis to full species rank, as well as the presence of three Evolutionary Significant Units (ESUs) within this newly delimited species, including one grouping all H. p. brigidai specimens. Alternatively, under lineage-based species concepts, our results support at least five evolutionary species in Hylexetastes: H. stresemanni; H. undulatus; H. perrotii; H. uniformis; and H. brigidai. Each of these taxa and ESUs are distributed in different interfluvial areas of the Amazon basin, which have different degrees of disturbance. Because they occupy the most heavily impacted region among all Hylexetastes ESUs, regular assessments of the conservation statuses of H. p. brigidai and both H. uniformis ESUs are paramount.
