Common Firecrest - Taxonomy

Taxonomy

The kinglets are a small group of birds sometimes included in the Old World warblers, but frequently given family status, especially as recent research shows that, despite superficial similarities, the crests are phylogenetically remote from the warblers. The names of the family, Regulidae, and its only genus, Regulus, are derived from the Latin regulus, a diminutive of rex, "a king", and refer to the characteristic orange or yellow crests of adult kinglets. The Common Firecrest was first formally described by Dutch zoologist Coenraad Jacob Temminck in 1820 as Sylvia ignicapilla; the relatively late identification of this common European bird arose from a perception that it was just a variety of the Goldcrest. The species name is derived from Latin ignis "fire" and capillus "hair". The binomial is frequently given as R. ignicapillus due to a misunderstanding of Latin grammar.

There are two widely recognised subspecies of Common Firecrest, nominate R. i. ignicapilla and Mediterranean R. i. balearicus (Jordans, 1923). The latter form is found on the Balearic Islands and in north Africa, and is slightly paler below and greyer above than the nominate subspecies. Other subspecies have been claimed, including southeastern R. i. caucasicus, North African R. i. laeneni, and Crimean R. i. tauricus. The Madeira Firecrest, R. madeirensis, was formerly also considered to be a subspecies of the Common Firecrest, but phylogenetic analysis based on the cytochrome b gene showed that the Madeiran form is distinct at the species level. Cytochrome b gene divergence between the Madeira Firecrest and the European bird is 8.5%, comparable with the divergence level between other recognised Regulus species, such as the 9% between the Goldcrest and the Golden-crowned Kinglet. The island form also differs in morphology and vocalisations. The proposed split was accepted by the Association of European Rarities Committees (AERC) in 2003, although some authorities, like The Clements checklist, have not yet recognised the new species.

The Flamecrest or Taiwan Firecrest (Regulus goodfellowi) of Taiwan has sometimes been viewed as a race of the Common Firecrest; however, the Flamecrest's territorial song, which resembles those of the Himalayan races of the Goldcrest, and genetic data indicate that the Flamecrest is closely related to the Himalayan Goldcrest and only distantly to the two Firecrest species. The kinglets on the Canary Islands, which were also considered to be close to Firecrests, have now been shown to comprise two subspecies of Goldcrest.