The Grenfell fossil site is a paleontological

Paleontology

Paleontology "old, ancient", ὄν, ὀντ- "being, creature", and λόγος "speech, thought") is the study of prehistoric life. It includes the study of fossils to determine organisms' evolution and interactions with each other and their environments...

 site of late Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

 age in the central west of New South Wales

New South Wales

New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...

, Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. It was discovered in the late 1970s and lies near the town of Grenfell

Grenfell, New South Wales

Grenfell is a country town in the Central West of New South Wales, Australia, in Weddin Shire. It is 370 kilometres west of Sydney and five hours' drive from the city. It is close to Forbes, Cowra and Young. At the 2006 census, Grenfell had a population of 1,994.-History:Prior to European...

, some 370 km west of Sydney

Sydney

Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...

, and has been the subject of ongoing investigations by the Australian Museum

Australian Museum

The Australian Museum is the oldest museum in Australia, with an international reputation in the fields of natural history and anthropology. It features collections of vertebrate and invertebrate zoology, as well as mineralogy, palaeontology, and anthropology...

.

The Grenfell site is important as the youngest locality for Devonian fossil

Fossil

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

s in New South Wales, containing a diverse range of placoderm

Placodermi

Placodermi is a class of armoured prehistoric fish, known from fossils, which lived from the late Silurian to the end of the Devonian Period. Their head and thorax were covered by articulated armoured plates and the rest of the body was scaled or naked, depending on the species. Placoderms were...

, acanthodian

Acanthodii

Acanthodii is a class of extinct fishes, sharing features with both bony fish and cartilaginous fish. In form they resembled sharks, but their epidermis was covered with tiny rhomboid platelets like the scales of holosteans...

 and sarcopterygian

Sarcopterygii

The Sarcopterygii or lobe-finned fishes – sometimes considered synonymous with Crossopterygii constitute a clade of the bony fishes, though a strict classification would include the terrestrial vertebrates...

 fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

es. The fossils are found in the Hunter Siltstone formation, of which there are extensive outcrops in the hills around Grenfell. The fish are mainly disarticulated but not extensively damaged, indicating transport after death by running water for a short distance.

Fossil fauna

Sarcopterygians found include Eusthenodon gavini, Mandageria fairfaxi, Cabonnichthys burnsi, Yarimba thomsoni, Grenfellia meemanae and Holoptychius

Holoptychius

Holoptychius is an extinct genus of porolepiform lobe-finned fish from the Devonian period. It is known from fossils worldwide.Holoptychius was streamlined predator about long, which fed on other bony fish. Its rounded scales and body form indicate that it could have swum quickly through the water...

sp. The placoderm genera Bothriolepis

Bothriolepis

Bothriolepis was the most successful genus of antiarch placoderms, if not the most successful genus of any placoderm, with over 100 species found on every continent.-Description and palaeobiology:...

, Remigolepis, Groenlandaspis

Groenlandaspis

Groenlandaspis is an extinct genus of armored placoderm.Groenlandaspis was a member of the Order Arthrodira, the most successful group of placoderms which also included the superpredator Dunkleosteus...

and Grenfellaspis are also present.