MONTANA

NATRON COUNTY

"MESAVERDE" FORMATION

JUDITHIAN AGE

CAMPANIAN STAGE

SENONIAN SUBEPOCH

UPPER GULF EPOCH

LATE CRETACEOUS

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: REPTILIA LAURENTI, 1768

SUBCLASS: DIAPSIDA OSBORN, 1903

INFRACLASS: NEODIAPSIDA BENTON, 1985

LEGION: LEPIDOSAUROMORPHA BENTON, 1983

SUBLEGION: LEPIDOSAURIA HAECKEL, 1866 (DUMERIL & BIBRON, 1839)

MAGNORDER: SQUAMATA, OPPEL, 1811

SUPERORDER: LACERTILIA OWEN, 1842

GRANDORDER: SCINCOGEKKONOMORPHA SUKHANOV, 1961

MICRORDER: SCINCOMORPHA CAMP, 1923

ORDER: ANGUIMORPHA FURBRINGER, 1900

SUBORDER: DIPLOGLOSSA COPE, 1864

INFRAORDER: OPHISAUROMORPHA ALIFANOV, 2000

Family: ANGUIDAE Gray, 1825

Subfamily: GLYPTOSAURINAE Marsh, 1872

Tribe: MELANOSAURINI Sullivan, 1979

Odaxosaurus piger

INFRAORDER: THECAGLOSSA COPE, 1890

PARVORDER: MONSTERSAURIA NORELL & GAO, 1977

Superfamily: VARANOIDEA Gray, 1827 (sensu Camp, 1923)

Family: MOSASAURIDAE Gervais, 1853

Infrafamily: NATANIA

Subfamily: RUSSELLOSAURINAE

Tribe: PLIOPLATECARPINI Dollo, 1884 (sensu Russell, 1967)

Platecarpus sp