BETWEEN GRAHAM AND ROOKS COUNTIES
LOWER SMOKY HILL MEMBER
NIOBRARA FORMATION
SANTONIAN OR CAMPANIAN STAGE
SENONIAN SUBEPOCH
GULF EPOCH
LATE CRETACEOUS
STEM: TETRAPODA GOODRICH, 1930
SUPERCLASS: AMNIOTA HAECKEL, 1866
CLASS: REPTILIA LAURENTI, 1768
SUBCLASS: DIAPSIDA OSBORN, 1904
SUPERLEGION: NEODIAPSIDA BENTON, 1985
LEGION: ARCHOSAUROMORPHA HUENE, 1946
SUPERCOHORT: AVEMETATARSALIA BENTON, 1999
COHORT: PROLACERTIFORMES CAMP, 1945 NOVA
SUPERORDER: TAPINOPLATIA PETERS, 2000
GRANDORDER: CHARACIOPODA PETERS, 2000
MICRORDER: FENESTRASAURIA PETERS, 2000
ORDER: PTEROSAURIA KAUP, 1834
SUBORDER: EUPTERODACTYLOIDEA BENNETT, 1994
Superfamily: PTERANODONTIDEA Marsh, 1876
Family: NYCTOSAURIDAE Bennett, 1989
*Nyctosaurus nanus
= Pteranodon nanus