Gray-lored Broadbill Serilophus rubropygius is split from Silver-breasted Broadbill S. lunatus (Clements 2007:264)

Summary: The Gray-lored Broadbill is now recognized as a distinct species occurring west of the Ayeyarwady (Irrawaddy) River of Myanmar and in the eastern Himalayas.

Details: Serilophus rubropygius of the eastern Himalayas to western Myanmar was described to science as a new species, but without having been explicitly compared to S. lunatus of southeast Asia (Hodgson 1839). For many years rubropygius was treated as a full species and was thought to be sympatric with S. lunatus in the Chin Hills (Garthwaite and Ticehurst 1937), though no proof of sympatry has emerged (Dekker and Dickinson 2000), and most sources at least since Peters (1951) have treated rubropygius as one of several subspecies within lunatus. Nevertheless, there appears to be ample evidence of parapatry on either side of the Irrawaddy (Ayeyarwady) River between the single western taxon rubropygius and the lunatus group, all of which differ from rubropygius conspicuously and consistently in wing coloration and especially feather shapes, as well as in bare yellow skin in the lores and bordering the bill base, lacking in rubropygius. ML images show that both taxa occur in different parts of Yunnan, southwestern China. Though the simple vocalizations of rubropygius and lunatus seem very similar, and no genetic analysis including both is yet published, the strong evidence of striking differentiation in parapatry has led WGAC and Clements et al. (2023) to agree with HBW and BirdLife International (2022) and Gill et al. (2023; v.13.2) in considering rubropygius a distinct species from the lunatus complex.

English names: The English name Gray-lored Broadbill highlights one of the best distinguishing characteristics of Serilophus rubropygius from the more widely distributed Silver-breasted Broadbill S. lunatus, which has bare yellowish lores.