A Global Molecular Phylogeny of the Small Puffinus Shearwaters and Implications for Systematics of the Little-Audubon's Shearwater Complex
Résumé
—A molecular phylogeny based on 917 base pairs (bp) of the mitochondrial (mt) DNA cytochrome-b gene was used to test and reassess the systematics and confl icting taxonomic treatments of the small, black-and-white Puffi nus shearwaters, including the P. assimilis–lherminieri species complex. Three geographically discrete clades were identifi ed in the North Atlantic, Southern (Australasia) and tropical Pacifi c and Indian oceans that contain most of the P. assimilis–lherminieri taxa. Together with four other lineages (P. puffi nus, P. opisthomelas, P. mauretanicus–P. yelkouan, P. newelli–P. myrtae), they form an unresolved polytomy. Puffi nus hu oni–P. gavia, P. nativitatis, and P. subalaris are basal to this. The phylogenetic positions of P. myrtae and P. subalaris are unexpected and warrant further investigation. None of the competing taxonomic treatments of the P. assimilis–lherminieri complex are supported. Instead, our phylogeny suggests that 14 taxa should be recognized, whereas fi ve others (loyemilleri, colstoni, nicolae, polynesiae, and atrodorsalis) are phylogenetically undiff erentiated from more widespread species (lherminieri, dichrous, and bailloni) and are probably not valid. Similarities in plumage and external morphological characters between unrelated species and diff erences between closely related species suggest that those traditional taxonomic characters are poor indicators of phylogenetic relatedness.