Heishanoolithus

Heishanoolithus Temporal range: Early Cretaceous PreꞒ Ꞓ O S D C P T J K Pg N
Egg fossil classification
Basic shell type:	Ornithoid
Morphotype:	Ornithoid-ratite
Oofamily:	†Elongatoolithidae
Oogenus:	†Heishanoolithus Zhao and Zhao, 1999
Oospecies
†H. changii Zhao and Zhao 1999 (type)

Heishanoolithus is an oogenus of Elongatoolithid fossil egg from the Shahai Formation in Liaoning. It is known only from seven eggshell fragments. It is most notable for having a very thin eggshell (1.2-1.3 mm thick), the dense covering of nodes on the eggshell surface, and for its relatively thin mammilary layer (making up only one eighth of the eggshell thickness).^[1] While no remains of Heishanoolithus have been associated with skeletal remains, strong evidence links Elongatoolithid eggs to Oviraptorosaurs.^[2]

References

1. Zhao H. and Zhao Z. (1999) "A New Form of Elongatoolithid Dinosaur Eggs from the Lower Cretaceous Shahai Formation of Heishan, Liaoning Province." Vertebrata PalAsiatica, 37(4): 278-284.
2. Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications. Archived 2016-03-04 at the Wayback Machine" (Doctoral dissertation, Montana State University, Bozeman).