Kakuru
Encyclopedia
Kakuru is a genus
of theropod dinosaur
from the early Cretaceous Period.
Kakuru is known primarily from a single fossil
ized tibia
, which had been fossilized through a rare process in which the bone through hydration
turned to opal
. The bone has been dug up at the opal fields of Andamooka, South Australia
. The opalized tibia was exhibited by a gem shop in 1973 and by chance brought to the attention of paleontologist Neville Pledge. The owner at the time, a certain A. Fleming, allowed pictures and two casts to be made but eventually the specimen was sold at an auction to an anonymous buyer. It was presumed lost to science. In 2004 however, the South Australian Museum
succeeded in procuring the fossil for $22,000.
Kakuru was formally named in 1980 by Pledge and Ralph Molnar
. The type species
is Kakuru kujani. The generic name is that of a Rainbow Serpent
of Australian Aboriginal mythology
. The specific name is that of the local aboriginal tribe, the Kujani or Guyani.
One of the casts is the plastoholotype, SAM P17926. The specimen was discovered in the marine Marree Formation dating from the Aptian
. Apart from the tibia, the find included some small probable fibula fragments. Later a foot digit was referred that might have come from the same species, specimen SAM P18010, but the assignment is dubious. The tibia is broken into about ten larger pieces and roughly 33 centimetres long. It is very slender in build and shows the impression of the ascending process of the astragalus
, an ankle bone itself lost. The process seems to have been very long and narrow.
Kakuru is believed to have been carnivorous, was bipedal and about two to three meters in length. This small dinosaur seems to have had long, slender legs.
Due to the paucity of the remains it has been difficult to establish the phylogenetic position of Kakuru. Molnar and Pledge gave no more precise determination than a Theropoda
incertae sedis
. The tibia provides two indications: its gracile form and the tall height and narrow width of the astragalar process. Both seems to point to the Coelurosauria
, perhaps the Oviraptorosauria
. However, in 2005 Oliver Rauhut pointed out that the Abelisauroidea also have a high ascending process of the astragalus.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of theropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
from the early Cretaceous Period.
Kakuru is known primarily from a single fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
ized tibia
Tibia
The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....
, which had been fossilized through a rare process in which the bone through hydration
Mineral hydration
Mineral hydration is an inorganic chemical reaction where water is added to the crystal structure of a mineral, usually creating a new mineral, usually called a hydrate....
turned to opal
Opal
Opal is an amorphous form of silica related to quartz, a mineraloid form, not a mineral. 3% to 21% of the total weight is water, but the content is usually between 6% to 10%. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most...
. The bone has been dug up at the opal fields of Andamooka, South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
. The opalized tibia was exhibited by a gem shop in 1973 and by chance brought to the attention of paleontologist Neville Pledge. The owner at the time, a certain A. Fleming, allowed pictures and two casts to be made but eventually the specimen was sold at an auction to an anonymous buyer. It was presumed lost to science. In 2004 however, the South Australian Museum
South Australian Museum
The South Australian Museum is a museum in Adelaide, South Australia, founded in 1856. It occupies a complex of buildings on North Terrace in the cultural precinct of the Adelaide Parklands.-History:...
succeeded in procuring the fossil for $22,000.
Kakuru was formally named in 1980 by Pledge and Ralph Molnar
Ralph Molnar
Ralph E. Molnar is a paleontologist who had been Curator of Mammals at the Queensland Museum and more recently associated with the Museum of Northern Arizona. He is also a research associate at the Texas natural Science Centre. He co-authored descriptions of the dinosaurs Muttaburrasaurus, Kakuru,...
. The type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
is Kakuru kujani. The generic name is that of a Rainbow Serpent
Rainbow Serpent
The Rainbow Serpent is a common motif in the art and mythology of Aboriginal Australia. It is named for the snake-like meandering of water across a landscape and the colour spectrum caused when sunlight strikes water at an appropriate angle relative to the observer.The Rainbow Serpent is seen as...
of Australian Aboriginal mythology
Australian Aboriginal mythology
Australian Aboriginal myths are the stories traditionally performed by Aboriginal peoples within each of the language groups across Australia....
. The specific name is that of the local aboriginal tribe, the Kujani or Guyani.
One of the casts is the plastoholotype, SAM P17926. The specimen was discovered in the marine Marree Formation dating from the Aptian
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...
. Apart from the tibia, the find included some small probable fibula fragments. Later a foot digit was referred that might have come from the same species, specimen SAM P18010, but the assignment is dubious. The tibia is broken into about ten larger pieces and roughly 33 centimetres long. It is very slender in build and shows the impression of the ascending process of the astragalus
Astragalus
Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere...
, an ankle bone itself lost. The process seems to have been very long and narrow.
Kakuru is believed to have been carnivorous, was bipedal and about two to three meters in length. This small dinosaur seems to have had long, slender legs.
Due to the paucity of the remains it has been difficult to establish the phylogenetic position of Kakuru. Molnar and Pledge gave no more precise determination than a Theropoda
Theropoda
Theropoda is both a suborder of bipedal saurischian dinosaurs, and a clade consisting of that suborder and its descendants . Dinosaurs belonging to the suborder theropoda were primarily carnivorous, although a number of theropod groups evolved herbivory, omnivory, and insectivory...
incertae sedis
Incertae sedis
, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...
. The tibia provides two indications: its gracile form and the tall height and narrow width of the astragalar process. Both seems to point to the Coelurosauria
Coelurosauria
Coelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. In the past, it was used to refer to all small theropods, although this classification has been abolished...
, perhaps the Oviraptorosauria
Oviraptorosauria
Oviraptorosaurs are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot - like skulls, with or without bony crests atop the head...
. However, in 2005 Oliver Rauhut pointed out that the Abelisauroidea also have a high ascending process of the astragalus.
External links
- Kakuru kujani on Alphalink.com.au by Molnar and Pledge, 1980.
- The Theropod Database on Kakuru