''Songlingornis'' is a prehistoric

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

from the Early

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

. Its

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 preserved ...

s have been found in the Jiufotang Formation of

Liaoning Liaoning () is a coastal province in Northeast China that is the smallest, southernmost, and most populous province in the region. With its capital at Shenyang, it is located on the northern shore of the Yellow Sea, and is the northernmost ...

( PRC). The age of these rocks is somewhat disputed, but probably around the early

Aptian The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous Epoch or Series and encompasses the time from 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ago), a ...

, 125-120 million years ago. Only one

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, ''Songlingornis linghensis'', is known at present. It was a close relative of ''

Yanornis ''Yanornis'' () is an extinct genus of fish-eating Early Cretaceous birds. Two species have been described, both from Liaoning province, People's Republic of China, China: ''Yanornis martini'', based on several fossils found in the 120-million-ye ...

'' and together with this and ''

Yixianornis ''Yixianornis'' (meaning "Yixian Formation bird") is a bird genus from the early Cretaceous period. Its remains have been found in the Jiufotang Formation at Chaoyang (People's Republic of China) dated to the early Aptian age, around 120 million ...

'' forms a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

of early modern birds. It is sometimes considered to be the same genus as ''Yanornis'' (which, described after ''Songlingornis'', would then be merged into that

taxon In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

), but this is not universally accepted.Mortimer (2004)

Footnotes

References

* (2006): Insight into the evolution of avian flight from a new clade of Early Cretaceous ornithurines from China and the morphology of ''Yixianornis grabaui''. ''Journal of Anatomy'' 208 (3):287-308.
PDF fulltextElectronic Appendix
* (2004) Enantiornithine Bird with Diapsidian Skull and Its Dental Development in the Early Cretaceous in Liaoning, China. ''Acta Geologica Sinica'' 78(1): 1–7. * (1997) Mesozoic Birds of China, Phoenix Valley Provincial Aviary, Taiwan: 153 pp. * (2004): The Theropod Database

Retrieved 2013-MAR-02. Early Cretaceous birds of Asia Bird genera Songlingornithids Fossil taxa described in 1997 Jiufotang fauna {{paleo-bird-stub