Australia: The Land Where Time Began

A biography of the Australian continent 

The first dinosaur bone, the Cape Paterson Claw, to be found in Australia, was found at a nearby site, Cape Paterson, in 1903, though it was not completely described until 1906. There is a spectacular rock formation known as Eagle Rock. The Flat Rock fossil site is on the coast of Victoria about 150 km southeast of Melbourne. The Dinosaur Dreaming dig site began in 1994. The rocks of the area, along the Strzelecki coastline, have been dated to the Early Cretaceous, between 120 and 115 million years ago.

At least 5 different types of dinosaur have been found in this area, and birds, mammals, reptiles and fish. The fossils in the site were deposited in a river, many of the bones being washed into the river from the surrounding valley.

Dinosaurs

Qantassaurus intrepidus, a hypsilophodontid, bipedal, about 1.8 m long and about 50 cm at the hip, about the size of a small wallaby. The description of this species is from a fragment of a lower jaw. The jaw differed from the that of other members of its family in having 12 teeth instead of the 14 teeth usually found in the family. The smaller number of teeth suggests its snout was shorter than in other family members.

Serendipaceratops arthurcclarkei, based on a fragmentary bone from the forearm that appears most closely similar to that of Leptoceratops from Canada. All other known ceratopsians come from Asia and North America.

Based on the presence of very small dinosaur bones it is believed the site may have been a dinosaur nesting area. Ankylosaurs and theropod remains have also been found in the area.

An ankle bone (talus) that has been found is very similar, if not actually identical, to that of Allosaurus. Whether or not it is the bone of an allosaurid is disputed, but there is little doubt that if had been discovered in the Northern Hemisphere it would have been assigned to an Allosaurus. There is also a problem with the age of the Cape Paterson fossil, it came from a deposit that was 25 million years younger than any known Allosaurus in the Northern Hemisphere. The animal it came from was small for an allosaurid, being about 5-6 m long and about 2 m high at the hip. The known allosaurids from the Northern Hemisphere were up to double the size of the Australian fossil. Whether or not the talus came from an Allosaurus is being debated, but if it isn't an Allosaurus it would be from the same family or even the same genus. It was the youngest known representative of its lineage.

Fulgatherium, a bone that is very similar to bones at Lightning Ridge from the same genus.

Amphibians

The jawbone of a labyrinthodont was found, a labyrinthodont, that had been believed to have gone extinct 90 million years earlier in the Triassic. It is the youngest known labyrinthodont in the world.

Koolasuchus, a labyrinthodont, an ambush predator,

Pterosaurs

Some teeth and bones found in the area are believed to be from pterosaurs

Aquatic reptiles

Teeth from small freshwater plesiosaurs have been found, as well as bones of primitive, short-necked turtles.

Mammals

Ausktribosphenous nyktos, order Ausktribophenos, an insectivorous mammal about the size of a mouse. A 17 mm long jaw with 4 teeth of this animal that were found in 1997 were similar to those of placentals, but placentals were not believed to have been present at such an early time. It's description as a placental has been disputed and agreement has not been reached on whether it was placental or monotreme. This animal was similar to modern shrews. A very similar jaw from the area was called Bishops. The 2 mammals found in this area are among the oldest known in the world. See monotremes.htm, slightly older mammals are known from Canada.

Among the many mammal jaws found at the site were of Teinolophus truslen, the oldest and smallest known monotreme.

A jaw fragment with a tooth is believed to represent a group of extinct mammals, Multituberculates.

Fish

There are many fish fossils in these deposits.

Birds

There is one bird bone found at Flat Rock, as well as a number of other possible bird bones that are being studied. Other Early Cretaceous evidence of birds have been found at Koonwarra, 40 km to the north.

Sources & Further reading

John A Long, Dinosaurs of Australia and New Zealand, University of New South Wales Press