Tuesday, May 15, 2018

[Ornithology • 2017] Heliangelus zusii An Extinct Hummingbird Species That Never Was: A Cautionary Tale About Sampling Issues in Molecular Phylogenetics


Phylogenetic relationships among species and populations of AglaiocercusTaphrolesbia, the Rogitama hybrid hummingbird, and Heliangelus zusii based on sequences of the ND2 mitochondrial gene. Strongly supported nodes (0.95 Bayesian posterior probability, 80% maximum-likelihood bootstrap) are indicated with black dots. Although nodal support for deep branches is low, note that both the Rogitama bird and H. zusii have haplotypes closely allied to those of A. kingii from the Eastern Andes of Colombia, indicating they are both hybrids sharing A. kingii as female parent.
in Perez-Eman, Ferreira, Gutierrez-Pinto, et al., 2017.
 DOI:  10.1101/149898  

Illustrations courtesy of Lynx Edicions; Handbook of the Birds of the World, Vol. 15, 1999.

Abstract
The Bogota Sunangel (Heliangelus zusii) was described based on a historical specimen lacking locality data as a striking - and potentially extinct - new species of hummingbird more than two decades ago. However, it was considered a dubious taxon by some researchers until a molecular study with strong species-level taxon sampling revealed its phylogenetic affinities and validated its status as a distinct species. We reanalysed existing mitochondrial DNA data together with a new data set sampling multiple populations of the Long-tailed Sylph (Aglaiocercus kingii), a species broadly distributed in the Andes of South America. In contrast to previous work, we found that H. zusii shares a haplotype with specimens of A. kingii from the Eastern Cordillera of Colombia, which is phylogenetically nested within a clade formed by populations of A. kingii from the Colombian Andes. These results suggest that H. zusii is not a distinct species, but is most likely the result of hybridization between a female A. kingii and a male of another hummingbird species. These findings highlight the importance of thorough taxonomic and geographic sampling when assessing the likelihood of hybrid origin of an organism, particularly in cases potentially involving wide-ranging species in areas where deep phylogeographic structure is likely.
Keywords: Aglaiocercus, geographic sampling, Heliangelus zusii, hybridization, phylogeography.


Figure 1. (A) Geographic ranges of Aglaiocercus kingiiAcoelestis, and Taphrolesbia griseiventris in northern South America (polygons), and geographic provenance of specimens of these species and of the Rogitama hybrid hummingbird included in molecular phylogenetic analyses (dots and star).

Figure 1. (A) Geographic ranges of Aglaiocercus kingiiAcoelestis, and Taphrolesbia griseiventris in northern South America (polygons), and geographic provenance of specimens of these species and of the Rogitama hybrid hummingbird included in molecular phylogenetic analyses (dots and star).
(B) Phylogenetic relationships among species and populations of AglaiocercusTaphrolesbia, the Rogitama hybrid hummingbird, and Heliangelus zusii based on sequences of the ND2 mitochondrial gene. Strongly supported nodes (0.95 Bayesian posterior probability, 80% maximum-likelihood bootstrap) are indicated with black dots. Although nodal support for deep branches is low, note that both the Rogitama bird and H. zusii have haplotypes closely allied to those of A. kingii from the Eastern Andes of Colombia, indicating they are both hybrids sharing A. kingii as female parent.

 Illustrations courtesy of Lynx Edicions; Handbook of the Birds of the World, Vol. 15, 1999.



Jorge L. Perez-Eman, Jhoniel Perdigon Ferreira, Natalia Gutierrez-Pinto, Andres M. Cuervo, Laura N. Cespedes, Christopher C. Witt and Carlos Daniel Cadena. 2017. An Extinct Hummingbird Species That Never Was: A Cautionary Tale About Sampling Issues in Molecular Phylogenetics. bioRxiv. DOI:  10.1101/149898