''Shanweiniao'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of long-snouted

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 Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

s from

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

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 ...

. One

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

is known, ''Shanweiniao cooperorum''. There is one known

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 ...

, a slab and counterslab. The fossil is in the collection of the Dalian Natural History Museum, and has accession number DNHM D1878/1 and DNHM1878/2. It was collected from the Lower Cretaceous Dawangzhengzi Beds, middle

Yixian Formation The Yixian Formation (; formerly Romanization of Chinese, transcribed as Yihsien Formation or Yixiang Formation) is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans the Barremian stage of the Early Cretaceous. I ...

, from

Lingyuan Lingyuan () is a city in the west of Liaoning province in Northeast China, bordering Hebei province and Inner Mongolia. It is under the administration of Chaoyang City, which lies to the east-northeast. Administrative Divisions There are eight ...

in the

Liaoning Province ) , 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 , ...

, China. O'Connor et al. (2010) found that ''Shanweiniao'' is a close relative of ''

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 ...

'', '' Longirostravis'', and ''

Rapaxavis ''Rapaxavis'' a genus of enantiornithean bird. It has been found in the Jiufotang Formation in Liaoning, People's Republic of China. In 2006 a specimen was reported, discovered by Pan Lijun at Xiaioyugou near the town of Lianhe, and referred to ...

'', which together form a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

of long-beaked enantiornithean birds, the

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 ...

. The genus name ''Shanweiniao'' () means "fan-tailed bird" in Chinese. The authors report that ''Shanweiniao'' is the only known enantiornithean bird with a tail surface capable of generating lift, as in modern birds. They also report that only one other Mesozoic bird, '' Yixianornis grabaui'', which is a basal

ornithuran Ornithurae (meaning "bird tails" in Greek) is a natural group that includes modern birds and their very close relatives such as the ichthyornithines and the hesperornithines. This clade is defined in the ''PhyloCode'' by Juan Benito and collea ...

, has been reported with this fan-shaped tail feather morphology. In a subsequent publication O'Connor ''et al.'' (2016) stated that interpretations of the tail morphology of this species are speculative due to incomplete preservation of the feathers of the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

specimen. The authors noted that longipterygid enantiornithines like ''Shanweiniao'' had very robust

pygostyle Pygostyle is a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component o ...

s even by enantiornithine standards, while birds preserving clear evidence for aerodynamic rectricial arrangements (''

Sapeornis ''Sapeornis'' is a monotypic genus of avialan dinosaurs which lived during the early Cretaceous period ( late Barremian to early Aptian, roughly 125-120 mya). ''Sapeornis'' contains only one species, ''Sapeornis chaoyangensis''. Description ...

'', ''

Chiappeavis ''Chiappeavis'' is a genus of enantiornithean bird from Early Cretaceous of northeastern China. The only species is ''Chiappeavis magnapremaxillo''. ''Chiappeavis'' is classified within the family Pengornithidae. It is known from a single, almo ...

'', members of

Ornithuromorpha Euornithes (from Greek ' meaning "true birds") is a natural group which includes the most recent common ancestor of all avialans closer to modern birds than to the enantiornithines. This group was defined in the ''PhyloCode'' by Juan Benito and ...

) had relatively more delicate pygostyles. O'Connor ''et al.'' (2016) also reported presence of narrow spaces visible between some of the tail feathers of the holotype specimen of ''Shanweiniao cooperorum''. The authors considered it more likely that ''Shanweiniao'' had

rachis In biology, a rachis (from the [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachi ...

-dominated tail feathers similar to feathers present in ''

Paraprotopteryx ''Paraprotopteryx'' is a genus of enantiornithean birds from the Mesozoic of China.Zheng, X. Zhang, Z. & Hou, L. (2007) A new enantiornithine bird with four long rectrices from the Early Cretaceous of northern Hebei, China. ''Acta Geologica Sini ...

''. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

, ''cooperorum'', is after Carl and Lynn Cooper who donated funds to support the study of

Mesozoic The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian r ...

birds in China. Though originally interpreted as an arboreal bird, it appears to have been terrestrial in habits, ranking with taxa like

megapode The megapodes, also known as incubator birds or mound-builders, are stocky, medium-large, chicken-like birds with small heads and large feet in the family Megapodiidae. Their name literally means "large foot" and is a reference to the heavy leg ...

s and

lark Larks are passerine birds of the family Alaudidae. Larks have a cosmopolitan distribution with the largest number of species occurring in Africa. Only a single species, the horned lark, occurs in North America, and only Horsfield's bush lark occ ...

References

{{Taxonbar, from=Q7489119 Longipterygidae Early Cretaceous birds of Asia Yixian fauna Cretaceous China Fossil taxa described in 2009