Phylogeny of the mourning wheatear Oenanthe lugens complex.

ABSTRACT

The phylogenetic relationship of many species and subspecies within the genus Oenanthe (wheatears) is still debated. Only recently molecular approaches have been used to clarify their basal taxonomy. One of the main unsolved groups is summarized under the name mourning wheatear O. lugens, which comprises depending on the underlying species concept 3-8 different taxa. These include the wheatears of the subspecies group lugens (halophila, lugens, persica), the subspecies group lugubris (lugubris, schalowi, vauriei), and the subspecies group lugentoides (lugentoides, boscaweni). In order to shed light on this unsolved issue we studied the taxonomy of the mourning wheatear complex by means of molecular markers and comparative morphometry. We found reasonable evidence to follow a narrow species concept treating all the three subspecies groups of the mourning wheatear in future as three independent taxonomic entities (super-species O. lugens, O. lugentoides, O. lugubris). Further within the subspecies group O. lugens we suggest treating halophila and lugens as members of the polytypic species O. lugens, while the Persian mourning wheatear O. persica merits the status of an independent monotypic species, endemic to the Iranian Plateau. Genetic and morphometric characters support a long separation of this form (a half to one Million years). For the black form "basalti" from Syria and Jordan our molecular data indicates a close relationship to lugens and this form is therefore probably best treated as a colour morph of lugens, adapted to the local habitat conditions. However, future behavioural studies have to show if there exist prezygotic barriers between both forms.