Oogenus: Youngoolithus ZHAO 1979
Etymology: In honor of C. C. Young and Greek, oo, "egg" and Greek, lithus, "rock or stone."

Oospecies: xiaguanensis ZHAO, 1979
Etymology: In reference to Xiaguan Town, Xiaguan Basin, Neixian County, Henan Province, China.

Holotype: IVPP V 5783 (Field number 75029)

Locality: 0.5 km northeast of Houzhuang Village, Xiaguan Town, Xiaguan Basin, Neixian County, Henan Province, China.

Horizon: Unnamed Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material: 16 eggs.

Referred material:

XIAOSI, LIWU, CHENG, ZOU, PANG, QANG, CHEN, ZHEN, WANG, LIU, XIE & JIN, 1998

Locality: Houying, Xixia County, Henan Province, China.

Horizon: Zoumagang Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material:

Number: Not given: Eggs and eggshells.

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Oospecies: xipingensis XIAOSI, LIWU, CHENG, ZOU, PANG, QANG, CHEN, ZHEN, WANG, LIU, XIE & JIN, 1998
Etymology: In reference to where the specimens were found, Xiping.

Holotype: Slice no. 1-37/93127

Locality: Xiping, Diangou of Yangcheng, Xixia County, Henan Province, China.

Horizon: Zoumagang Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material: Eggs and eggshells.

Paratype:

Slice section No. 1-72/95GD-F-1: