The Wallumbilla Formation is a Lower Cretaceous geologic formation found in Australia. Plesiosaur

Plesiosaur

Plesiosauroidea is an extinct clade of carnivorous plesiosaur marine reptiles. Plesiosauroids, are known from the Jurassic and Cretaceous Periods...

 remains are among the fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s that have been recovered from its strata.

The formation is present in the Northern Territory, Queensland, South Australia, and New South Wales. It is a sedimentary unit, principally made up of mudstone and siltstone, with calcareous concretions. Its maximum thickness is 600 meters. Its age is somewhere from Aptian

Aptian

The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...

 to Albian

Albian

The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...

, that is between 113 and 98 Mya. The formation is part of the Wilgunya Sibgroup, which in turn is part of the Rolling Downs Group of the Eromanga

Eromanga Basin

The Eromanga Basin is a large Mesozoic sedimentary basin in central and northern Australia. It covers parts of Queensland, the Northern Territory, South Australia, and New South Wales, and is a major component of the Great Artesian Basin...

 and Surat Basin

Surat Basin

The Surat Basin is a part of the Great Artesian Basin of Australia. The Surat Basin extends across an area of 270,000 square kilometres and the southern third of the basin occupies a large part of northern New South Wales, the remainder is in Queensland. It comprises Jurassic through to Cretaceous...

s. The named beds are: Coreena, Doncaster, Jones Vally, Ranmoor, and Trimble Members.

Paleofauna

Placeholder Placeholder Placeholder may refer to:In language:* Placeholder name, words that can refer to objects or people, whose names are unknown or irrelevant* Filler text, shares some characteristics of a real written text, but is random or otherwise generated... s of the Placeholder Formation
Genus	Species	Location	Stratigraphic position	Abundance	Notes	Images
Notopala Notopala Notopala is a genus of large, freshwater snails with an operculum, aquatic gastropod mollusks in the family Viviparidae, the river snails or mystery snails.- Description :... Cotton, 1935	† Notopala albascopularis (Etheridge, 1902)	White Cliffs, New South Wales White Cliffs, New South Wales White Cliffs is a small town in outback New South Wales in Australia, in Central Darling Shire. White Cliffs is around 255 km northeast of Broken Hill, 93 km north of Wilcannia. At the 2006 census, White Cliffs had a population of 119....			the oldest freshwater snail Freshwater snail A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions.... in Australia