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Science News

Hunt for the "Magpie Fiddler".

South Australian Museum scientists are on the hunt for a rare relative of the stingrays, the Magpie Fiddler.

The ray is known from only a handful of specimens all found in the waters of Gulf St Vincent. First described by scientists nearly 50 years ago, the Magpie Fiddler is a striking black and white ray that reaches almost one metre in length.

Local Adelaide region fishers are familiar with the Southern Fiddler, which is often caught on fishing lines set for King George Whiting in the shallow waters of the Gulf St Vincent. The Magpie Fiddler is a close relative of this more common Southern Fiddler.

So far specimens of the Magpie Fiddler have only been seen in the Gulf St Vincent and in the nearly 50 years since coming to the notice of scientists only one has ended up in the South Australian Museum scientific collection.

Because virtually no specimens have been available for study, museum scientists have not been able to verify that the Magpie Fiddler is indeed a separate species from the more common Southern Fiddler. Some doubts have arisen since the initial description of the species in 1954. However, because of the advancements associated with DNA technology it is now possible to test the status of the magpie fiddler.

The South Australian Museum is a world leader in using DNA technology to solve problems in biodiversity research. The essential requirement for this research is tissue samples from individuals of the problem species. From these samples, museum scientists can isolate the DNA sequences that reveal the identity of each species.

The South Australian Museum is now starting a large research program aimed at compiling DNA profiles of the fishes of South Australia. The case of the Magpie Fiddler is just the first of many identification problems of South Australian fishes that remain unsolved.

The museum is seeking the help of all South Australian fishers by asking them to keep a lookout for both the rarer Magpie Fiddler and the common Southern Fiddler as both are needed for the comparison of DNA profiles.

Anyone catching a fiddler can assist this project by either bringing it to the museum within hours of capture, or shipping it frozen or chilled. Specimens can also be handed into National Parks offices that have freezer facilities in Mt Gambier, Port Lincoln, Ceduna or Murrayâs Lagoon on Kangaroo Island.

SA Museum Contacts:

Stephen Donnellan, (82077479, Evolutionary Biology Unit)

Mark Hutchinson (82077461, Vertebrate Department)

Terry Sim (82077473, Collection Manager of Fishes)

Mike Gemmell (82077406, Information Services)

Scientists from the South Australian Museumâs Mammal Section and Evolutionary Biology Unit and students from the University of Adelaideâs Molecular Biosciences and Environmental Biology Departments have recently solved the mystery of how many species of common dolphin are present in southern Australian waters. The study, funded in part by a grant from the Sea World Research and Rescue Foundation Inc, investigated the molecular make-up, and the shape and size of skulls and skeletons of common dolphins that died from various causes and were found along the southern coast of Australia.

Click here for the full story and an identifcation guide for dolphins in South Australia.

12th October, 2001
110 million year old fossil CAT scan ö world first

Rare images were captured today of a 110 million year old ichthyosaur, in what was a world first. With the help of the Royal Adelaide Hospital CAT scans were performed to aid in research.

Ichthyosaurs were fast swimming marine reptiles resembling dolphins. The ichthyosaur lived in Australiaâs Inland Sea while Dinosaurs dominated earth in the Early Cretaceous period.

Ben Kear, Palaeontologist, South Australian Museum and George Kourlis, Senior Radiographer, Royal Adelaide Hospital performed the CAT scans this morning which produced amazing images and revealed structures of the ichthyosaur that have never been seen before.

From the cat scans taken Ben will be able reconstruct soft tissue to see how the marine reptile lived 110 million years ago. The scans have provided important clues to the animalâs biology, behaviour and how it might have lived. These include features such as:

• It was deaf

• It had excellent vision

• Details about a possible skin sensory system that may have allowed it to pick up electrical signals in the water (like a shark)

• What the brain would of looked like

As well as vital research and information the cat scans will produce 3D images that will be used for display in the South Australian Museumâs new Fossil Gallery, the first stage of which is now open.

4th October 2001
Rare 30 million year old plant fossil identified

A rare and spectacular 30 million year old plant fossil which consists of rare and very delicate fern frond fragment has been identified by Professor Bob Hill, Head of Science at the South Australian Museum, Dr Mike Macphail from the Australian National University and Dr Greg Jordan, University of Tasmania.

The rare discovery was found in a fossil deposit in North Western Tasmania two years ago. Tasmania has provided a wealth of plant fossil data, demonstrating the link Australia had with other Southern continents when part of the super continent Gondwana.

The exciting feature about this identification is that these fern frond fragments are identical with a living South American species Lophosoria quadripinnata even though they are remote both in space and time. Outside of South America the fern is now globally extinct.

The exciting aspect of this discovery is that the Tasmanian fossil fronds belong to this living species from South America. For this to be correct the living species Lophosoria quadripinnata must have survived unchanged in both Australia and South America for at least 50 million yearsö an occurrence that changes the way we think about the duration of the species..

Paper now in press:
Hill, R.S., Macphail, M.K. & Jordan, G.J. in press. Macrofossils associated with the fossil fern spore Cyantheacidites annulatus and their significance for Southern Hemisphere biogeography. Review of Palaeobotany and Palynology.

17th August, 2001
Dolphin remains found in whale stomach

Scientists from the South Australian Museum, lead by research scientist Sue Gibbs, have confirmed the remains of at least three dolphins have been found in the stomach of a young male killer whale, most of which had been cut with a blade, indicating human involvement.

The killer whale (Orcinus orca) washed up dead on the beach at Emu Bay, Kangaroo Island, on December 7, 1999. Three weeks previous to this the same whale was reported to be stranded in shallow water at Tulka, near Port Lincoln.

When found, the animal had been dead for some time and due to decomposition, cause of death has never been established. South Australian Museum staff, assisted by the RSPCA and National Parks and Wildlife Officers, collected the skeleton of the whale and samples for further investigation.

The recent examination of the stomach contents of the killer whale, in March 2001, revealed more than 20kg dolphin pieces . The remains included intact flippers, many bones, chunks of blubber and the skin from the head of a dolphin.

It is believed the dolphin pieces may have been used as bait, a practice not unknown in South Australia. In the early 1990âs, under state law, fishermen appeared in court charged with having on board pieces of at least four common dolphins used as bait.

Hiding for 33 years in the Museum

It doesn't happen often that species are brought back from the dead but this is did occur recently at the Museum. While looking at skulls of the swamp rat Rattus lutreolus in the mammal collection, the Curator noticed, through the side of the plastic container, a skull from Kangaroo Island that didn't look quite right. Closer inspection revealed that it wasn't a true rat (Rattus spp.) at all, yet there are no native rodents which are not true rats on Kangaroo Island.

Excitement built as the possibilities were considered but extra care was needed as it is easy to make a mistake when one really wants "a good find". Fortunately there was also a study skin from the same animal and when this was checked it was quite clear what the animal was a heath rat Pseudomys shortridgei. It had been collected in 1967 on the edge of Flinders Chase National Park. At the time it was collected, it was believed to have been the first record of the swamp rat for Kangaroo Island!

Until this amazing discovery, the only specimens of heath rats in South Australia were subfossils from the Southeast, Kangaroo Island, Eyre Peninsula and Yorke Peninsula. Subfossils can be hundreds or even thousands of years old so from only these records one cannot say whether a species occurred in South Australia when Europeans arrived. Obviously this one did but it took over 150 years to discover this.

This exciting find reaffirms what we behind the scenes at the Museum already know but which is often overlooked by other scientists and the public. Specimens must be taken and lodged in permanent collections. They are available for scientists to study (and often reidentify) sometime down the track. Long live curators who still dabble in the collections under their care!

22nd March 2000:
First Triassic fossil amphibian found in South Australia

A recent fossil discovery at Leigh Creek has excited palaeontologists, who have identified it as part of a labyrinthodont amphibian from the late Triassic Period.

The find is the first record of this group of animals in South Australia, and the first record for the late Triassic Period in Australia.

The South Australian Museum's Curator of Fossils, Neville Pledge, said he had been hoping for such a discovery for more than 30 years. (Previously, the only vertebrate animal fossils known from the locality were two partial fish, one found nearly 50 years ago.) The identification was confirmed recently by fossil amphibian expert, Dr Anne Warren of La Trobe University, Melbourne, and the South Australian Museum's Curator of Herpetology, Dr Mark Hutchinson.

The fossil was discovered last December by bulldozer driver Danny Gilbert while removing shale overburden at Flinders Power's Leigh Creek coal mine. Mr Gilbert then notified Team Leader Roger Kennewell, who assisted in the recovery of the fossil. They passed it on to the mine-site geologist, Dr John Bamberry, who realised its significance and sent it to the South Australian Museum. "I was amazed that the fossil was found," Dr Bamberry said later. "The fossil was found on the night shift, not the easiest conditions to see in!"

The specimen appears as a mass of brownish material against a grey shaly background. It is not, at this stage, easily interpreted, due to sediment still covering parts of the bone. It is about 30 cm long and almost as wide, with a broad semicircular mass at one end and several apparent ribs and part of the back-bone, and represents the shoulder region and part of the body of the animal. Unfortunately, the large head and the limbs and tail were not found. This means that scientists will be unlikely to be able to give the animal a proper scientific name unless another specimen is found. It is estimated that the animal would have been about 2 metres long in life, with a broad head, nearly twice as wide as the present fragment.

Labyrinthodont amphibians were amongst the first vertebrate animals to leave the water to live on dry land, late in the Age of Fishes - the Devonian Period, some 370 million years ago. They reached their peak in the Triassic Period about 210-260 million years ago, and in most places died out at the end of that time. In Australia, they are best known from the early Triassic, but have also been found in younger rocks in Queensland (Jurassic age) and Victoria (Cretaceous age - the youngest in the world). But, until now, they had not been found in late Triassic rocks in Australia. First indications suggest that the Leigh Creek fossil is quite similar to these younger species.

The fossil has been given to the South Australian Museum for the State Collection, and is available for photographing at the Museum.