A comprehensive taxonomic revision of the subalpine warbler complex has concluded that it contains three species-level taxa.
With Moltoni's Warbler already recognised as a split by the IOC, the most significant conclusion of the recently published research is therefore the recognition that Eastern and Western Subalpine Warblers should also be treated as full species in their own right.
Subalpine Warblers have long been the subject of scrutiny from scientists, but due to a number of unanswered questions – such as the exclusion of North African inornata from recent genetic studies – the much-anticipated three-way split hadn't yet been formally recognised.
However, this comprehensive new genetic study from Zuccon et al finally provides the confirmation needed, having used samples taken in the breeding season throughout the three species' ranges, crucially including North Africa. Significantly, this North African taxon, inornata, was found to be invalid, thus rendering Western Subalpine Warbler a monotypic species.
The authors recommend that the subalpine warbler complex is now classified as follows.
Moltoni's Warbler Sylvia subalpina. Monotypic; range extending across north-central Italy, Corsica, Sardinia and the Balearic Islands.
Western Subalpine Warbler Sylvia iberiae. Monotypic; North Africa (Tunisia to Morocco), Iberia, southern France, and north-west Italy.
Eastern Subalpine Warbler Sylvia cantillans. Polytypic, consisting of:
- Sylvia cantillans cantillans of southern Italy and Sicily;
- Sylvia cantillans albistriata of north-east Italy, the Balkans, Greece, and western Turkey.
Zuccon, D, Pons, J-M, Boano, G, & 14 others. 2020. Type specimens matter: New insights on the systematics, taxonomy and nomenclature of the subalpine warbler (Sylvia cantillans) complex. Zoological Journal of the Linnean Society. doi:10.1093/zoolinnean/zlz169