Old World Warblers (Sylviidae)

Isabelline Warbler (Hippolais opaca) - HBW 11, p. 636

French: Hypolaïs obscure German: Isabellspötter Spanish: Zarcero Bereber
Other common names: Western Olivaceous Warbler

Taxonomy: Hypolais[sic] opaca Cabanis, 1850, Senegal.
Recent molecular-genetic studies suggest that this species and H. caligata, H. rama and H. pallida are closer to Acrocephalus than to current congeners and could be placed in a separate genus, Iduna. Was formerly regarded as a race of H. pallida, but recent work has demonstrated substantial differences between the two in mitochondrial DNA (more than 9%), song, behaviour and morphology, and treatment as separate species seems warranted. Monotypic.

Distribution: Breeds N, E & S Spain, also NW Africa in Western Sahara, much of Morocco, and E along coastal range and N mountains in Algeria and Tunisia (S to S slopes of Atlas) apparently to coastal NW Libya; non-breeding W Africa.