Elongatoolithus

Elongatoolithus Temporal range: Late Cretaceous PreꞒ Ꞓ O S D C P T J K Pg N
Elongatoolithus excellens nest in CosmoCaixa Barcelona.
Egg fossil classification
Basic shell type:	Ornithoid
Morphotype:	Ornithoid-ratite
Oofamily:	†Elongatoolithidae
Oogenus:	†Elongatoolithus Zhao, 1975
Type oospecies
†Elongatoolithus andrewsi Zhao, 1975
Oospecies
See text

Elongatoolithus is an oogenus of dinosaur eggs found in the Late Cretaceous formations of China and Mongolia. Like other elongatoolithids, they were laid by small theropods (probably oviraptorosaurs), and were cared for and incubated by their parents until hatching. They are often found in nests arranged in multiple layers of concentric rings. As its name suggests, Elongatoolithus was a highly elongated form of egg. It is historically significant for being among the first fossil eggs given a parataxonomic name.