Systematics and Nomenclature of the Andean Swallow, "Petrochelidon" andecola

Abstract

Andean Swallow is a relatively little-known species inhabiting Puna zone (3,100-4,600 m) of Andes of Peru, northern Chile, and Bolivia, and possibly northwestern Argentina (FjeldsA and Krabbe 1990). It was described by Lafresnaye and d'Orbigny in 1837 from a Bolivian specimen in Paris Museum and, like most swallow species, was originally placed in all-encompassing Linnaean swallow genus Hirundo, with specific name andecola. It is a mediumsized swallow (mass 14-19 g; Turner and Rose 1989), weakly iridescent bluish or greenish above, and grayish-white below with a brownish throat. Since its original description, Andean Swallow has been moved about in a number of genera and its relationships debated. Sharpe (1885) synonymized andecola with Brown-bellied Swallow, which he identified with Hirundo of Gmelin, 1789, and placed in genus Atticora, then a sort of wastebasket genus for a miscellany of Neotropical swallows. Hellmayr (1935) considered Gmelin's name to be unidentifiable, and used next oldest species name for Brown-bellied Swallow (Petrochelidon murina Cassin, 1853), while adopting for it generic name Orochelidon proposed by Ridgway (1903). Although Ridgway mentioned only murina in differentiating Orochelidon from Atticora, Neochelidon, and Notiochelidon, Peters (1960) pointed out that, in a later publication, Ridgway (1904) included andecola in his new genus as well. Peters could find no characters to separate Orochelidon from Notiochelidon, and placed Brown-bellied Swallow, but not Andean Swallow, in Notiochelidon, where it remains in modern literature (Turner and Rose 1989). Meanwhile Berlepsch and Stolzmann (1896) had demonstrated that Sharpe was in error in synonymizing andecola with cinerea Gmelin (=murina Cassin), and that andecola was a good species. Possibly influenced by Sharpe, they placed andecola in Atticora. That large genus subsequently has been reduced to extent that it now includes only two species, fasciata and melanoleuca, both of which differ from andecola in several ways, including possession of long, forked tails. Chapman (1924) divided andecola into two subspecies, naming oroyae based on three adults and an immature bird from Oroya and Chipa, Peru, using color characters and greater bill width of oroyae in his diagnosis. With only a pair before him, Hellmayr (1935) was skeptical about validity of oroyae. Zimmer (1955) reexamined type series and not only verified Chapman's color characters, but found that oroyae had a significantly longer wing, a difference overlooked by both Chapman and Hellmayr. In his description of oroyae, Chapman (1924:12) made following comments: The cliff swallows form such an obviously natural group that I hesitate to add to their genus a species that does not wear their distinctive pattern of marking and which is not known to build their peculiar type of nest. But facts that I cannot find one good generic character separating this species from Petrochelidon and that in juvenal plumage andecola has upper tail-coverts strongly tinged with ochraceous-tawny indicate that it may be placed in this genus without undue violence to either systematic or biologic ornithology. Todd (1929), definitely a splitter at generic level, pointed out that Ridgway (1904; erroneously cited by Todd as 1902) had dismembered old genus Atticora Boie, placing each species in a monotypic genus except for andecola, which, as mentioned above, he placed in his recently described genus Orochelidon. Todd completed dismemberment of old Atticora by creating a new monotypic genus, Haplochelidon, for andecola. Todd stated he could not follow Chapman in referring this species to Petrochelidon, the very points he brings up arguing against such a disposition. Nevertheless, all subsequent authors have followed Chapman rather than Todd, and kept andecola either in Petrochelidon (Peters 1960) or in a broadened Hirundo that included Petrochelidon (Turner and Rose 1989, Sibley and Monroe 1990). Chapman (1924) had pointed out that it was not then known whether andecola built a typical Petrochelidon mud-pellet nest. In a landmark paper, Mayr and Bond (1943) presented a tentative reclassification of swallows, giving major importance to structure as a character. They mentioned fact that nesting habits of andecola were unknown, and went on to say: Its nidification should either prove or disprove its relationship with typical 'Petrochelidon.' If nesting habits of this swallow are like those of species included above under 'A', recognition of Todd's Haplochelidon would seem justified. Their category A included species with nest placed in a crevice among rocks or in a building, hole in a tree, or in a burrow; no mud used in construction. first description of nesting habits of Andean Swallow appeared in first Spanish-language edition of Las Aves de Chile by Goodall et al.