Phylogenomics and species delimitation of a complex radiation of Neotropical suboscine birds (Pachyramphus)

Mol Phylogenet Evol. 2018 Jan:118:204-221. doi: 10.1016/j.ympev.2017.09.013. Epub 2017 Sep 22.

Abstract

Phylogeographic studies within the Neotropics continue to uncover hidden diversity, the extent of which remains poorly known. In birds, molecular studies are producing evidence that species-level diversity is substantially underestimated. Many avian taxa comprise large complexes of subspecies that often represent species-level taxa by various criteria. One such group of Neotropical suboscine birds, the becards (Pachyramphus), ranges from Argentina through northern Mexico. Their taxonomic limits have been complex and controversial as the genus has bounced around a number of suboscine families. Additionally, the phylogenetic relationships within Pachyramphus are unresolved due to insufficient sampling of taxa and populations across species' ranges. We used target capture of ultraconserved elements for 62 individuals representing 42 taxa, and sequenced two mitochondrial genes and two nuclear introns covering 265 individuals of 51 taxa, including all recognized species, resulting in the most densely and completely sampled phylogenetic hypothesis for Pachyramphus to date. We delimited species using a traditional taxonomic approach and then tested them under a Bayesian multi-species coalescent framework. In doing so, we provide evidence for multiple young, previously undetected evolutionary lineages within Pachyramphus. Deep, well-supported branches and a high number of intraspecific lineages across the tree suggest that at least 50% of species diversity may be unrecognized.

Keywords: BP&P; Multi-species coalescent; Phylogenomics; Speciation; Ultraconserved elements; Underestimated diversity.

MeSH terms

  • Animals
  • Argentina
  • Base Sequence
  • Bayes Theorem
  • DNA, Mitochondrial / genetics
  • Genetic Loci
  • Genomics*
  • Likelihood Functions
  • Mexico
  • Passeriformes / classification*
  • Passeriformes / genetics*
  • Phylogeny*
  • Phylogeography
  • Species Specificity
  • Tropical Climate*

Substances

  • DNA, Mitochondrial