NEBRASKA
SAUNDERS COUNTY
NEAR VALPARAISO
ADOLPH REZAC FARM
GRANEROS SHALE
MIDDLE CENOMANIAN STAGE
UPPER MIDDLE GALLIC SUBEPOCH
LOWERMOST GULF EPOCH
MIDDLE CRETACEOUS
STEM: TETRAPODA GOODRICH, 1930
SUPERCLASS: AMNIOTA HAECKEL, 1866
CLASS: REPTILIA LAURENTI, 1768
SUBCLASS: DIAPSIDA OSBORN, 1904
INFRACLASS: EURYAPSIDA COLBERT, 1945
SUPERORDER: SAUROPTERYGIA OWEN 1860
GRANDORDER: EOSAUROPTERYGIA emend RIEPPEL, 1994
ORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835
SUBORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835
INFRAORDER: PLESIOSAUROMORPHA NOVA
EUPLESIOSAURIA O’KEEFE, 2001
Superfamily: ELASMOSAUROIDEA Cope, 1869
Family: ELASMOSAURIDAE Cope, 1869
Subfamily: STYXOSAURINAE Otero, 2016
*Styxosaurus rezaci
= Thalassomeodon haningtoni