Dinosaur Dreaming report 2003

[Dann Pigdon <dannj@alphalink.com.au>]

D I N O S A U R   D R E A M I N G
  Flat Rocks Site Report 2003


Yep, it's that time of year again. The time: the Early Cretaceous. The
place: south eastern Victoria, Australia. Your mission, if you choose to
accept it... okay, enough of that. To the goods already.

Two more mammal jaw fragments brings the total to 23 found over the last
10 years, representing at least three genera (the micro-monotreme
Teinolophos, and the ausktribosphenes A.niktos and Bishops). One of last
season's specimens appears to be another Teinolophos. Although it lacks
teeth, it preserves the back part of the jaw that is missing in the type
specimen. It is currently being studied by Prof. James Hopson of the
Uni. of Chicago, and Anne Musser of the Uni. of New South Wales, along
with Tom Rich himself. This specimen indicates that the lower jaw of
Teinolophos was comprised of four bones; the dentary, and facets that
indicate three additional bones that had been reduced to splints. This
is the first monotreme mandible to show anything but a single bone (the
dentary). This seems to indicate that monotremes split from the
ancestors of placentals and marsupials well before they split from each
other, perhaps indicating that marsupials are closer to placentals than
either are to monotremes.

Four small hypsie dentaries were recovered; three of them with only one
tooth each. The weird thing is it's the same tooth in each case. They're
too gracile to be Qantassaurus, so they're either new species, or
existing types known only by femora. All dentaries are about 4cm in
length, and the tooth types are different from Leaellynasaura,
Atlascopcosaurus or Qantassaurus.

Five more theropod teeth were found, bring the total from this area to
around 70. Prelimiary studies by Phil Currie on 40 of the teeth from
previous seasons indicates at least four distinct taxa were present. A
recent article about two small claws found in Queensland said: "Until
now, evidence of Australian coelurosaurs - raptors the size of a turkey
- had been limited to fossilised footprints, such as those at Lark
Quarry, 110 km (68 miles) southwest of Winton." Obviously they chose to
ignore the Victorian finds. Queensland can have its giants - the least
they can do is credit Victoria with the small stuff!

A single ankylosaur tooth resembling that of Minmi was found. Anky teeth
are rare in these deposits; only about 6 so far. Dermal ossicles however
are known in their hundreds. One of the purported anky teeth has a
divided root. Ankylosaur specialist Dr Tatyana Tomanova from the
Paleontological Institute, Moscow, will visit later this year to take a
look at the material.

Some small gracile bones have been tentatively classified as a bird
humerus and perhaps a pterosaur tibia. The bird furcula found last year
has been studied by a 3rd year Geoscience student (I would assume at
Monash University), who concluded that it most closely resembles that of
enantiornithines (no surprise there; Nanantius is known from
Queensland).

Many of the fossils prepared from previous seasons form part of a
travelling exhibit that is currently in the Fukui Prefectural Dinosaur
Museum in Japan. In fact there was a strong Japanese contingent in this
years fieldwork, since the Dinosaur Dreaming crew members were teaching
Japanese volunteers how to identify fossil bone amongst the coal and
plant fragments in the matrix. The amateur Japanese palaeontologist
Kenji Baba was also interested in the training proceedures themselves,
since he has worked similar deposits in Japan. The group of seven
Japanese volunteers was led by Dr Yoshitaka Yabumoto from Kitakyushu
Museum.

The presence of Raul Vacca, a Patagonian preparator in Australia to
mount a cast of Cryolophosaurus (which I believe is currently on display
in Woolongong near Sydney), made the season a truly international event
(expecially given the Riches American accents). The mounted skeleton
will also end up in Japan.

There is also interesting news on the palynological front. Apparently
the biodiversity of pollen/spores in deposits from the periglacial (or
cryoturbational) periods is low to moderate. Biodiversity of
pollen/spores in the longer and slightly warmer intervening periods
appears to be moderate to fair. The Flat Rocks deposits represent one of
the colder (periglacial) periods. There are still three more
cryoturbation sites near Flat Rocks that have yet to be sampled for
pollen. So far a total of 33 species of pollen/spores are known from
several sampling points around Flat Rocks, with 47 species from the
Kilcunda Cliff site alone (which is representiative of the warmer
intervening periods). More samples from different areas should clarify
things further.

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Dann Pigdon                   Australian Dinosaurs:
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://www.alphalink.com.au/~dannj/
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