Australian_Geographic_-_December_2015_AU_

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N AUGUST I LED an AG Society
Scientific Expedition to Lightning
Ridge. It was the first fossil dig we
have hosted, and one of the most
exciting specimens we helped study
was a new meat-eating dinosaur, the
largest ever discovered in Australia.
Originally found by opal miners in
the 1990s, the fossil has only recently
been studied by Dr Phil Bell, palaeon-
tologist at the University of New
England in Armidale, NSW. The fossil
was discovered underground at the
Carters Rush opal field, and consists
of a giant claw from the hand; parts of
the arm, hip and foot; pieces of ribs;
and a whole bunch of other fragments.
“When I started looking at this
fossil last year, I immediately recog-
nised it was something new and
important. Comparing it with other
Australian and South American
dinosaurs it became clear this was a
megaraptorid – a relatively rare group
mostly known from Argentina,” says
Phil, who has published a study on the
find in the journal Gondwana Research.
Calculations suggested that the animal
would have been about 7m in length,
making it Australia’s biggest known
carnivorous dinosaur – bigger than
previous record-holder Australovenator,
described in 2009 from a fossil found
at Winton in Queensland.

There were just enough clues in
the new bones to identify the dinosaur


  • dubbed ‘Lightning Claw’ – as a
    megaraptorid. It would have been a
    large and slender predator that
    prowled the waterways and flood-
    plains of this region of the superconti-
    nent of Gondwana 110 million years
    ago, during the Cretaceous period.
    One unique feature of Lightning Claw
    is its massive claws, which may have
    been used like grappling hooks to
    ensnare prey – it lacked the powerful
    jaws of other carnivores, such as T. r e x.
    The fossil, mostly formed of
    blue-grey ‘potch’, or common opal,
    also displays flashes of precious opal
    when moved in the light. In 2005
    Lightning Ridge locals Rob and
    Debbie Brogan, who had acquired the
    dinosaur, donated it to the Australian
    Opal Centre (AOC), which has the
    world’s largest public collection of
    opalised fossils (see AG 124). The
    original specimen was almost certainly
    more complete, but wasn’t immedi-
    ately recognised as a fossil, and parts
    were destroyed or lost in the mining
    process. Phil – who has been working
    for several years alongside Jenni
    Brammall and Dr Elizabeth Smith of
    the AOC – has chosen not to officially
    name the animal as a new species until
    more complete fossils are found.


A new dinosaur is the biggest carnivore ever found Down Under.


“It’s another little piece of the
puzzle for Australian dinosaurs,” says
Dr Steve Salisbury, from the Univer-
sity of Queensland. It also cements
the idea that megaraptorids were
the dominant carnivores here in the
Cretaceous. Megaraptorids are
medium-sized meat-eaters – includ-
ing Megaraptor and Australovenator –
that lived on Gondwana at this time.
Australian dinosaurs have often
been thought of as aberrant or relict
species, living on the periphery of the
regions that produced new groups of
dinosaur, but Phil argues the new find
contests that notion. “Lightning Claw...
is the oldest member of this group of
megaraptorid dinosaurs,” he says. “The
evidence now points to an Australian
origin for this group – so they first
appeared here and branched out,
colonising other parts of the super-
continent, such as South America.”
Several other dinosaurs have been
described from Lightning Ridge
fossils, but each consists of just a
single bone. Lightning Claw is the
most complete Australian carnivore
known after Australovenator.

JOHN PICKRELL is the editor of AUSTRAL-
IAN GEOGRAPHIC. AGS-supported research will
continue on our 2016 Lightning Ridge fossil dig:
http://www.australiangeographic.com.au/issue

All hail ‘Lightning Claw’


Cretaceous carnivore.
This 7m killer once prowled
along Lightning Ridge’s
swamps, lakes and rivers.

AGS-supported research


JULIUS CSOTONYI


Turn to page
99 to participate
in our Gobi Desert
fossil dig scientific
expedition!

NATUR E

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