''Boluochia zhengi'' was an

enantiornithean The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and cl ...

bird. It lived during the Early Cretaceous in the time span 121.6-110.6 mya ( late Aptian- early Albian) and is known from

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s found in the

Jiufotang Formation The Jiufotang Formation () is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms (see Jehol Biota). It is a member of the Jehol group. T ...

Liaoning ) , image_skyline = , image_alt = , image_caption = Clockwise: Mukden Palace in Shenyang, Xinghai Square in Dalian, Dalian coast, Yalu River at Dandong , image_map = Liaoning in China (+all claims hatched).svg , ...

province,

People's Republic of China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

. ''Boluochia'' was first described by Zhou in 1995.Zhou, 1995. "Discovery of a New Enantiornithine Bird from the Cretaceous of Liaoning, China". PalAsiatica 33(2):99-113 A re-analysis of the specimen by

Jingmai O'Connor Jingmai Kathleen O'Connor ( ''Zōu Jīngméi''; born August 26, 1983) is a paleontologist who works as a curator at the Field Museum in Chicago, Illinois. Biography O'Connor is from Pasadena, California. Her mother is a geologist. O'Connor says ...

and colleagues found that it was closely related to ''

Longipteryx ''Longipteryx'' is a genus of prehistoric bird which lived during the Early Cretaceous (Aptian stage, 120.3 million years ago). It contains a single species, ''Longipteryx chaoyangensis''. Its remains have been recovered from the Jiufotang Forma ...

'' and could be assigned to the family

Longipterygidae Longipterygidae is a family of early enantiornithean avialans from the Early Cretaceous epoch of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125-120 million years ago. Descr ...

.O'Connor, J.K., Zhou Z. and Zhang F. (In press). "A reappraisal of ''Boluochia zhengi'' (Aves: Enantiornithes) and a discussion of intraclade diversity in the Jehol avifauna, China." ''Journal of Systematic Palaeontology'', (published online before print 16 December 2010). While it was originally described as having a hooked, raptorial beak, the specimen is badly preserved, and further research suggested that it instead had a normal, toothed, and probably elongated snout like other longipterygids. Though the only known specimen is very poorly preserved, in nearly all features that can be compared between the two, ''Boluochia'' is indistinguishable from a juvenile specimen of ''Longipteryx''. Jingmai O'Connor and colleagues, in a 2010 re-study of the specimen, could find only one concrete feature to distinguish them: in ''Boluochia'', the fourth metatarsal diverges significantly from the others, causing the outer toe to be separated from the rest when perched. The researchers who noted this characteristic argued that it was not likely to be a deformity because it was present on both feet, and that it was not a juvenile characteristic, as it is not seen in known juvenile specimens of ''Longipteryx''.

References

Bird genera Early Cretaceous birds of Asia Longipterygidae Fossil taxa described in 1995 Jiufotang fauna {{paleo-bird-stub