Eurasian Crag Martin - Taxonomy

Taxonomy

The Eurasian Crag Martin was formally described as Hirundo rupestris by Italian naturalist Giovanni Antonio Scopoli in 1769 and was moved to the new genus Ptyonoprogne by German ornithologist Heinrich Gustav Reichenbach in 1850. Its nearest relatives are the three other members of the genus, the Pale Crag Martin, P. obsoleta, the Rock Martin, P. fuligula, and the Dusky Crag Martin, P. concolor. The genus name is derived from the Greek ptuon (φτυον), "a fan", referring to the shape of the opened tail, and Procne (Πρόκνη), a mythological girl who was turned into a swallow. The specific rupestris means "of rocks", from the Latin rupes "rock". There are no generally recognised subspecies. Two races, Central Asian P. r. centralasica and P. r. theresae in the Atlas Mountains of Morocco, have been proposed, but the slight differences in size and colour show no consistent geographical pattern. Fossils of this species have been found in Late Pleistocene deposits in Bulgaria, and in central France in layers dated at 242,000 to 301,000 years ago.

The four Ptyonoprogne species are members of the swallow family of birds, and are placed in the Hirundininae subfamily, which comprises all swallows and martins except the very distinctive river martins. DNA studies suggest that there are three major groupings within the Hirundininae, broadly correlating with the type of nest built. The groups are the "core martins" including burrowing species like the Sand Martin, the "nest-adopters", which are birds like the Tree Swallow that utilise natural cavities, and the "mud nest builders". The Ptyonoprogne species construct an open mud nest and therefore belong to the last group; Hirundo species also build open nests, Delichon house martins have a closed nest, and the Cecropis and Petrochelidon swallows have retort-like closed nests with an entrance tunnel.

Ptyonoprogne is closely related to the larger swallow genus Hirundo into which it is often subsumed, but a DNA analysis showed that an enlarged Hirundo genus should logically contain all the mud-builder genera, including the Delichon house martins, a practice which few authorities follow. Although the nests of the Ptyonoprogne crag martins resembles those of typical Hirundo species like the Barn Swallow, the research showed that if Delichon, Cecropis and Petrochelidon are split from Hirundo, Ptyonoprogne should also be treated as a separate genus.