Serendipaceratops arthurcclarkei
Rich & Vickers-Rich 2003

Click image to enlarge
Leptoceratops
Colourised Image

Information
PRONOUNCED
    Seh-ren-dip-pah-sair-ah-tops
MEANING
    Pleasant surprise horned face
CLASSIFICATION
    ?Neoceratopia, Ceratopia, Marginocephalia
    Cerapoda, Genasauria, Ornithischia
AGE
    Early Cretaceous (Aptian) 115 MYA
FORMATION
    Wanthaggi Formation (Strzelecki Group)
    Also Otway Group
SIZE
    2 metres (7 feet) long?
LOCATION
    Inverloch, Victoria

In 1994 a fossil ulna (lower arm bone) was described by Drs Tom Rich and Patricia Vickers-Rich, after having been found in Early Cretaceous deposits in the Strzelecki group in Victoria a few years earlier. While in North America the two palaeontologists showed the ulna to several ceratopian experts. When laid next to the ulna of Leptoceratops gracilis from the Late Cretaceous (Maastrichtian) of Canada, it was generally agreed that the two bore a striking resemblence. In 2003 it was formally named Serendipaceratops arthurcclarkei.

The bone itself is about 16 centimetres long and is missing the olecranon process (otherwise known as the "funny bone"). Like all ceratopian ulnae it is short and deep, and is mediolaterally flattened. No other known type of dinosaur has an ulna like this, although it can not be ruled out that the Australian specimen may represent an as-yet unknown type of dinosaur that was found only in Australia, and that came to resemble ceratopians in at least this particular bone by chance. A second similar ulna, although only half the size, was recovered from Dinosaur Cove, dating to around 106 MYA.

This reconstruction is based entirely on Leptoceratops gracilis from the Late Cretaceous of Canada. It gives a good impression of what the "average" small protoceratopian would have looked like.

The Australian bone, if it is ceratopian, presents a problem. The earliest neoceratopian, Protoceratops andrewsi from Monglia, first appears in the fossil record about 30 million years after the date for the Australian material. Leptoceratops itself, which this bone most closely resembles, comes from the latest Late Cretaceous about 65 million years ago, which is around 50 million years later than the Australian bone. If the Australian material is accepted as ceratopian then it would place the origins of the neoceratopia much earlier than once thought, and on the opposite side of the planet.

(Neoceratopia refers to most ceratopians, or horned dinosaurs, more advanced than Psittacosaurus, including protoceratopians and the later true horned dinosaurs like Triceratops)

Ulnae comparison
Australian ulna
The Australian ulna compared
to Leptoceratops gracilis
Click image for larger version


Rich, T.H. and P.Vickers-Rich 1994 Neoceratopsians and ornithomimosaurs: dinosaurs of Gondwanan origin? Research and Exploration 10:129-131.

Rich, T.H. & P.Vickers-Rich 2003. Protoceratopsian? ulnae from the Early Cretaceous of Australia. Records of the Queen Victoria Museum No. 113.


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