Systematic review of the Cinnamon-throated Woodcreeper Dendrexetastes rufigula (Aves: Dendrocolaptidae) based on a multilocus phylogeography

Abstract

The Amazon is one of the most speciose regions in the world. Yet there are still undescribed and misidentified species, and scarce information about the biology of the described species in the region. Here, we evaluate for the first time the existence of genetically differentiated lineages within the polytypic species Dendrexetastes rufigula, an endemic Amazonian lineage. We identified three major evolutionary independent units using both mitochondrial (Cytb and ND2) and nuclear (G3PDH, BF5 and MUSK) markers that roughly corresponded to currently recognized subspecies. Although we found strong statistical support for the reciprocal monophyly of D. r. rufigula and D. r. devillei, we did not find reciprocal monophyly between D. r. moniliger and D. r. paraensis, which were paraphyletic. However, these two taxa grouped together in a clade with Bayesian but not bootstrap support. Moreover, clades D. r. rufigula, D. r. devillei, and D. r. moniliger/paraensis differed from each other by much higher mitochondrial genetic distances (between 1 and 2%), than that separating D. r. paraensis from D. r. moniliger (0.3 ± 0.1%). We add molecular evidence to the morphological data supporting that D. r. rufigula and D. r. devillei are highly diagnostic taxa that could be regarded as two distinct species. Conversely, although D. r. moniliger and D. r. paraensis are both genetically and morphologically distinct from either D. r. rufigula or D. r. devillei, D. r. moniliger and D. r. paraensis cannot be considered mutually independent evolutionary lineages. This result is particularly important from a conservation perspective, since D. r. paraensis is considered threatened in Brazil. Our results support that at least three main evolutionary lineages deserving evolutionary species status exist in the Cinnamon-throated Woodcreeper, and that the endangered lineage in the Belém area of endemism is a morphologically slightly distinct subset of a more widespread lineage endemic to southeastern Amazonia east of the Madeira River.