 The specific "cyanurus" is also derived from Greek, the roots being "kuanos", "dark-blue", and "oura", "tail".In the past generally treated as comprising two subspecies, "T. c. cyanurus" breeding in northern Asia and "T. c. rufilatus" breeding in the Himalaya, it is now increasingly being treated as monotypic, with "T. c. rufilatus" split off as a distinct species, Himalayan bluetail "T. rufilatus".The species has also been known by a variety of English and scientific names in the ornithological literature.