Ceramornis

Ceramornis is a genus of ornithuran dinosaurs from the Late Cretaceous. It lived shortly before the Cretaceous–Paleogene extinction event in the Maastrichtian, some 66 million years ago (mya).^[1] Its remains were found in the Lull 2 location, a Lance Formation site in Niobrara County, Wyoming. A single species is known, Ceramornis major, and even that only from a proximal piece of coracoid. This is specimen UCMP V53957, which was collected by a University of California team in 1958.^[2]

Size (lower middle right) compared to contemporary birds, pterosaurs, and a human

Ceramornis Temporal range: Late Cretaceous, 66 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Clade:	Avialae
Family:	†Cimolopterygidae
Genus:	†Ceramornis Brodkorb, 1963
Species:	†C. major
Binomial name
†Ceramornis major Brodkorb, 1963

Ceramornis has been placed in the family Cimolopterygidae together with Cimolopteryx and Lamarqueavis. Cimolopterygidae has sometimes been placed in the modern bird order Charadriiformes, based on quantitative analysis of its coracoid and comparison with other modern bird samples.^[3][4] However, there remains some uncertainty about the taxonomic position, as there is insufficient fossil material to be assessed by wide-scale cladistic analysis.^[5]

It is not certain that Charadriiformes was already distinct by the Maastrichtian.^[1]

References

1. Longrich, N. (2009). "An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada." Cretaceous Research, 30(1): 161-177.
2. Berkeley Natural History Museums: Specimen Account: V53957 (Ceramornis major). Retrieved 2007-NOV-04.
3. Federico L. Agnolin (2010). "An avian coracoid from the Upper Cretaceous of Patagonia, Argentina". Stvdia Geologica Salmanticensia. 46 (2): 99–119.
4. "†Ceramornis Brodkorb 1963 (shorebird)". Paleobiology Database. Retrieved 3 February 2023.
5. Mortimer (2004)