The Ryukyu kingfisher (''Todiramphus cinnamominus miyakoensis'') is an enigmatic taxon of

tree kingfisher The tree kingfishers, also called wood kingfishers or Halcyoninae, are the most numerous of the three subfamilies of birds in the kingfisher family, with around 70 species divided into 12 genera, including several species of kookaburras. Th ...

. It is extinct and is only known from a single specimen. Its taxonomic status is doubtful; it is most likely a subspecies of the

Guam kingfisher The Guam kingfisher (''Todiramphus cinnamominus'') is a species of kingfisher from the United States Territory of Guam. It is restricted to a captive breeding program following its extinction in the wild due primarily to predation by the introd ...

, which would make its scientific name ''Todiramphus cinnamominus miyakoensis''. As the specimen is at the Yamashina Institute for

Ornithology Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...

, the question could be resolved using DNA sequence analysis; at any rate, the Guam kingfisher is almost certainly the closest relative of the Ryukyu bird. The IUCN considers this bird a subspecies and has hence struck it from its redlist. The one known bird, probably a male, was according to its label collected on

Miyako-jima is the largest and the most populous island among the Miyako Islands of Okinawa Prefecture, Japan. Miyako Island is administered as part of the City of Miyakojima, which includes not only Miyako Island, but also five other populated island ...

, the main island of the Miyako group, Ryūkyū Shotō, on February 5, 1887. While it is often and correctly stated that specimen labels may be incorrect or misleading, the locality, to the northwest of the extant populations of ''Todiramphus cinnamominus'', seems sound in a biogeographical sense. At least the specimen labels of Ryukyu collections by later Japanese collectors are usually very reliable; whether this is true for earlier collection too is not known. The only differences between the Miyako-jima bird and males of the Guam kingfisher (the nominate subspecies of the Micronesian kingfisher; presently only surviving in captivity) are the former's lack of a black nape band and the red feet (black in Guam birds). The bill color is unknown due to damage to the specimen, and supposed differences in the proportion of the

remiges Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tai ...

are almost certainly an artifact of specimen preparation. Indeed, the specimen was not recognized as distinct until some 30 years after its collection. If the bird was indeed a resident of the Miyako group (and as there was better habitat on neighboring

Irabu-jima ( Miyako: ''Irav''), is an island in Miyakojima, Okinawa Prefecture, Japan. The island is connected to Miyako Island by a bridge , which was completed in January 2015. Irabu Island is also connected via six bridges to Shimoji-shima. There are ...

, it is probable that it would have been found there too), it became extinct in the late 19th century. While this seems early, the population must have always been small as there never was much habitat available in historic times. Certainly, thorough research in the early 20th century failed to find the bird again. The reasons for the disappearance of the population would have been land clearance and draining of wetlands for agriculture.

References

Todiramphus Controversial bird taxa Extinct birds of Oceania Extinct animals of Asia Extinct animals of Japan Birds of the Ryukyu Islands Birds described in 1919 Taxa named by Nagamichi Kuroda {{Coraciiformes-stub