Genus: Umoonasaurus KEAR, SCHROEDER & LEE, 2006
Etymology: Antakirinja, indigenous name for the Coober Pedy area, 'Umoona', and Greek, sauros, "lizard."

Species: demoscyllus KEAR, SCHROEDER & LEE, 2006
Etymology: Greek, demos, "of the people" and Greek, Scyll, a sea monster of classical mythology; referring to the type locality and purchase of the holotype specimen by public donations.
= Leptocleidus sp KEAR, 2006b

Holotype: AM F99374

Locality: Zorba Extension Opal Field, west of Coober Pedy, South Australia State, Australia.

Horizon: Bulldog Shale, Marree Subgroup.

Biostratigraphy: Correlates to the Cyclosporites hughesii, Crybelosporites stratus zones/Odontochitina operculata, Diconodinium davidii, and Muderongia tetracantha zones.

Age: Late Aptian-Early Albian Stage, Early Gallic Subepoch, Late Early Cretaceous Epoch, Late Early Cretaceous.

Material: Skull and skeleton.

Note: Two sections of gastric mass (sample 1, sample 2), total of 60 gastroliths, and associated 17 osteichthyan vertebrae.

Note: Opalized.

Referred material:

Locality: Andamooka opal fields, South Australia State, Australia.

Horizon: Bulldog Shale, Marree Subgroup.

Biostratigraphy: Correlates to the Cyclosporites hughesii, Crybelosporites stratus zones/Odontochitina operculata, Diconodinium davidii, and Muderongia tetracantha zones.

Age: Upper Aptian-Early Albian Stage, Early Gallic Subepoch, Upper Early Cretaceous Epoch, Upper Lower Cretaceous.

Material:

SAM P23841: Skeleton.

Note: Opalized.

 

Locality: Curdimurka area, Lake Eyre South, South Australia State, Australia.

Horizon: Bulldog Shale, Marree Subgroup.

Biostratigraphy: Correlates to the Cyclosporites hughesii, Crybelosporites stratus zones/Odontochitina operculata, Diconodinium davidii, and Muderongia tetracantha zones.

Age: Upper Aptian-Early Albian Stage, Early Gallic Subepoch, Upper Early Cretaceous Epoch, Upper Lower Cretaceous.

Material:

SAM P31050: Fragmentary skeleton.

 

Locality: Neales River Region, Oodnadatta, South Australia State, Australia.

Horizon: Bulldog Shale, Marree Subgroup.

Biostratigraphy: Correlates to the Cyclosporites hughesii, Crybelosporites stratus zones/Odontochitina operculata, Diconodinium davidii, and Muderongia tetracantha zones.

Age: Upper Aptian-Early Albian Stage, Early Gallic Subepoch, Upper Early Cretaceous Epoch, Upper Lower Cretaceous.

Material:

SAM P410550: Skeleton of a juvenile.

 

= Leptocleidus sp KEAR, 2006b

Locality: Andamooka, west of Lake Torrens, Eromanga Basin, north-eastern South Australia State, Australia.

Horizon: Bulldog Shale, Marree Subgroup.

Biostratigraphy: C. hughesii and C. striatus zones/O. operculata, D. davidii, and M. tetracantha zones.

Age: Lower Aptian-Lower Albian Stage, Middle Gallic Subepoch, Upper Early Cretaceous Epoch, Early Cretaceous.

Material:

SAM P15980: Fragmentary skeleton of a juvenile.

SAM P39915: Skeleton.

Note: Has a fused terminal 'pygostyle' of the terminal caudal vertebrae, Pathologic?