?Caenagnathid

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Caenagnathid

Information
PRONOUNCED
    Kay-nag-narth-id
MEANING
    "Strange jaw" family
CLASSIFICATION
    ?Oviraptorosauria, Maniraptora, Tetanurae, Theropoda
AGE
    Early Cretaceous (Albian) 106 MYA
FORMATION
    Otway Group
SIZE
    2-3 metres (6-10 feet) long?
LOCATION
    Dinosaur Cove, Victoria

Caenagnathids, and oviraptorosaurs in general, were bizarre looking theropod dinosaurs with toothless, almost parrot-like jaws. They are mostly known from the Late Cretaceous of Asia and North America, although fragmentary evidence from Australia and South America may indicate a Gondwanan origin for oviraptorosaurs. Microvenator celer is a possible primitive oviraptorosaur dating to about the same time as the Australian material, although from North America.

Vertebra Possible caenagnathid material in the form of a lower jaw fragment (right surangular, NMV P186386) and perhaps a vertebra (NMV P186302) were found at Dinosaur Cove in Southern Victoria (Otway ranges), dating to around 106 MYA. The jaw fragment shows similarities with that of dromaeosaurs, but is closer to that of caenagnathid oviraptorosaurs due to a pronounced medial inflection of the coronoid process. The isolated vertebra also shares some dromaeosaur and oviraptorosaur features, such as single pleurocoels on each side of the dorsal centrum (most other theropod groups have paired pleurocoels). Most other oviraptorosaur material is much younger (Late Cretaceous), however those species seem to have already been highly specialised by that time, perhaps suggesting that the oviraptorosaur line branched off from other theropod groups much earlier.

This reconstruction, based on extremely fragmentary material, is a "best guess" at what a primitive oviraptorosaur may have looked like. I have based it on Chirostenotes elegans (a Late Cretaceous North American caenagnathid), and on the more primitive Microvenator.

Re-evaluation of the Kakuru kujani tibia suggests that it may be similar to that of Ingenia yanshi, an oviraptorosaur from the Late Cretaceous (Campanian-Maastrichtian) of Mongolia. If so then perhaps this group was quite widespread throughout Southern Australia during the Early Cretaceous.


Currie, P.J., P.Vickers-Rich and T.H.Rich 1996 Possible oviraptorosaur (Theropoda, Dinosauria) specimens from the Early Cretaceous Otway Group of Dinosaur Cove, Victoria Alcheringa 20:73-79


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