Kakuru kujani
Molnar and Pledge 1980

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Colourised Image

See photographs of the type material.

    Rainbow serpent
    Incertae Sedis, Theropoda
    Early Cretaceous ?110 MYA
    Maree Formation
    1.5 to 2 metres (5 to 6.5 feet) long
    Andamooka, South Australia

Kakuru is known from an opalised almost complete tibia (shin bone). It was dug up somewhere in the opal fields of Andamooka in South Australia, and was first noticed in a shop window by palaeontologist Neville Pledge of the South Australian Museum in 1973. The fossil was sold, and remained in private hands for 30 years, until being bought by the South Australian Museum for $22,000 in 2004. The generic (first) name is from an Aboriginal legend and means "rainbow serpent", probably because being opalised the minerals sparkle with many colours in some places. The species (second) name is a variant spelling of the Guyani tribe which inhabited the area around Andamooka.

It was a small, perhaps carnivorous theropod about 1.5 to 2 metres (5 to 6 feet) in length. The above reconstruction comes out at 1.7 metres, with a short Avimimus-like tail. The structure of the tibia suggests that it belongs to a completely new family of theropod dinosaurs, unknown of anywhere else in the world. The tibia, when reconstructed, was found to be in two main sections which were separated by only a small gap of missing material. It measures 323 mm (about 13 inches) in total length. In form it resembles Calamospondylus foxii and Coelurus gracilis, especially in the distal (lower) end. In general proportions the tibia is similar to Microvenator celer and Ornitholestes hermanni.

Re-evaluation of the material may suggest a similarity between the tibia of Kakuru and that of the oviraptorosaur Ingenia yanshi, especially in the overall shape of the astragular groove, perhaps indicating that Kakuru may belong somewhere in the oviraptorosauria. An undescribed tibia and astragalus from Africa are also said to closely resemble the Kakuru material.

Morphing Animation So, how did I manage to reconstruct a dinosaur from a single incomplete bone? The distal (lower) end of the tibia is diagnostic for most theropods. Kakuru's tibia, although unique, closely resembles that of the bird-like Avimimus portentosus from the Late Cretaceous of Mongolia in some aspects. It is also similar to that of coelurosaurs and modern slender-legged wading birds. Since it seems to resemble Avimimus and Ingenia, with proportions similar to Microvenator, I took skeletal reconstructions of Avimimus and Microvenator (an oviraptorosaur of about the same age as Kakuru) and used morphing software to generate a theoretical skeletal reconstruction midway between the two.

The result is an interesting reconstruction of a small long-legged theropod, although of course being based on a single bone its accuracy is hard to determine.

Kakuru Tibia
The type specimen of Kakuru. Used with permission from the former owner

Long, J. & B.Choo 1998 Yet more on Australian dinosaurs. Dinonews 12:4-5. Western Australian Museum

Molnar, R.E. & N.S.Pledge 1980 A new theropod dinosaur from South Australia. Alcheringa 4:281-287.

Norman, D.B. 1990 Problematic Theropods: Coelurosaurs. In D.W.Weishampel, P.Dodson & H.Osmolska (eds), The Dinosauria. University of California Press, Berkeley. pp.280-317