The yellow-bellied flyrobin (Cryptomicroeca flaviventris) is a species of passerine bird in the Australasian robin family Petroicidae. It is the only species in the genus Cryptomicroeca. The yellow-bellied flyrobin is endemic to New Caledonia, where it occurs on the island of Grande Terre. It occupies a range of habitats, including dry lowlands, woodland, Pinus and Pandanus forest, and humid forest from sea level up to .
The yellow-bellied flyrobin was described in 1860 by the French ornithologists, Jules Verreaux and Oeillet des Murs, from a specimen collected in New Caledonia. They coined the binomial name Eopsaltria flavigastra.[1] The English ornithologist, Richard Bowdler Sharpe, realised that the specific epithet was preoccupied, and in 1903 he proposed flaviventris as a replacement.[2] The species was long considered one of the yellow robins of the genus Eopsaltria.[3] However, a 2009 genetic study showed it to be nested within the flyrobin genus Microeca,[4] and hence it was moved to Microeca, and its common name was changed from yellow-bellied robin to yellow-bellied flyrobin in the online list of world birds maintained by Frank Gill and David Donsker on behalf of the International Ornithological Committee (IOC).[5] A more comprehensive genetic study of the family Petroicidae, published in 2011, found that the yellow-bellied flyrobin was divergent from the other members of Microeca, and instead was sister to a clade containing the Microeca and the torrent flyrobin.[6] The yellow-bellied flyrobin is now placed as the only species in the genus Cryptomicroeca that was introduced in 2012.[5] [7]
The yellow-bellied robin is a medium-sized Australasian robin, in length and weighing around . The plumage is similar to members of the genus Eopsaltria: dark olive-grey back, tail and wings, grey head and chest with a slightly lighter throat, and yellow belly and rump. The legs are grey.