PROFILPELAJAR.COM

Cuspirostrisornis; Temporal range: Early Cretaceous, 120 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
	Life restoration of Cuspirostrisornis houi amid ginkgoes and araucaria pines
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Clade:	Avialae
Clade:	†Enantiornithes
Family:	†Avisauridae
Genus:	†Cuspirostrisornis; Hou, 1997
Species:	†C. houi
Binomial name
	†Cuspirostrisornis houi; Hou, 1997

Cuspirostrisornis is a genus of enantiornithean bird. Only one species is known, Cuspirostrisornis houi, though some researchers believe this to be a synonym of the similar species Cathayornis yandica.^[1] It is known from one fossil found in the Jiufotang Formation in Liaoning province, People's Republic of China. The Jiufotang Formation is dated to the Early Cretaceous period, Aptian age, 120.3 +/-0.7 million years ago.^[2]

C. houi is known from a nearly complete fossil. The holotype fossil is in the collection of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, China. The fossil is given catalog number IVPP V 10897. It was collected in 1993 by Dr. Hou Lianhai and Hou Jinfeng, the illustrator at IVPP. It was collected from light gray mudstones approximately two kilometers west of Boluochi Village, Chaoyang County, Liaoning Province.^[3]

The holotype fossil is that of a small perching bird, with a skull about 27 millimeters (1 inch) long. There are five pairs of tiny teeth in the premaxilla, and another five pairs in the anterior dentary. It had a pointed snout which Hou identified as a beak proportionally similar to the beaks of the extant genus Motacilla, the wagtails. However, some have noted that there is no evidence that the snouts of tooth-bearing prehistoric birds such as most enantiornitheans would also have possessed a horny beak, at least in a toothed part of the snout.^[4] As Cuspirostrisornis had a toothed snout, the beak which Hou presumed was present in the genus is likely a misinterpretation, similar to the hooked beak which was erroneously stated to be present in Boluochia, one of many other enantiornitheans described in the same paper.

The ulna is large and derived, with the s-shape of modern flying birds. The sternum is large, carinate, and broad.^[3]

Etymology

The generic name comes from the Latin words for "pointed" and "beak", and the specific name refers to its describer, Mr. Hou Jinfeng, who is mentioned above.

References

^ Zhou Z. and Wang Y. (2010). "Vertebrate diversity of the Jehol Biota as compared with other lagerstätten." Science China: Earth Sciences, 53(12): 1894–1907. doi:10.1007/s11430-010-4094-9 [1] Archived 2013-10-29 at the Wayback Machine
^ He, H.Y., Wang, X.L., Zhou, Z.H., Wang, F., Boven, A., Shi, G.H., Zhu R.X. (2004). "Timing of the Jiufotang Formation (Jehol Group) in Liaoning, northeastern China, and its implications". Geophysical Research Letters 31(13): 1709.
^ ^a ^b Hou, Lianhai (1997) "Mesozoic Birds of China" Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China. Published by the Phoenix Valley Provincial Aviary of Taiwan. In Chinese, translated by Will Downs, Bilby Research Center, Northern Arizona University, January, 2001.
^ O'Connor, Jingmai K.; Chiappe, Luis M. (2011). "A revision of enantiornithine (Aves: Ornithothoraces) skull morphology". Journal of Systematic Palaeontology. 9 (1): 135–57. Bibcode:2011JSPal...9..135O. doi:10.1080/14772019.2010.526639. S2CID 86503357.