An unusual new neosauropod dinosaur from the - PowerPoint PPT Presentation

Title: An unusual new neosauropod dinosaur from the


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An unusual new neosauropod dinosaur from the
Lower Cretaceous Hastings Beds Group of East
Sussex, England Michael P. Taylor and Darren
Naish School of Earth and Environmental
Sciences University of Portsmouth Portsmouth PO1
3QL ltdino_at_miketaylor.org.ukgt
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freaky
An unusual new neosauropod dinosaur from the
Lower Cretaceous Hastings Beds Group of East
Sussex, England Michael P. Taylor and Darren
Naish School of Earth and Environmental
Sciences University of Portsmouth Portsmouth PO1
3QL ltdino_at_miketaylor.org.ukgt
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Where to discover new dinosaurs (I)
Mike Benton at SVPCA 2005 suggested countries
such as Mongolia and Argentina ...
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Where to discover new dinosaurs (II)
... but the best unexplored territory is
still the basement of the Natural History Museum.
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Meet BMNH R2095
A single, partial mid-to-posterior dorsal
vertebra. That's not much material, but
Sauropod dorsals are very
diagnostic. This specimen
is highly apomorphic.
Briefly described by Lydekker (1893) when no-one
knew anything about sauropods. Subsequently
overlooked.
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Where it's from
Precise locality information is not preserved (if
it was ever recorded). Lydekker (1893) just said
from the Wealden of Hastings. But known to
have been collected by Rufford. Better documented
Rufford specimens are known to be from East
Cliff and Ecclesbourne Glen (both east of
Hastings)
R2095
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Age

• Stratigraphic information is not preserved.
• Units exposed both East Cliff and
• Ecclesbourne Glen are part of the
• Ashdown Beds Formation
• R2095 probably from Ecclesbourne Glen
• It is closer to Hastings than is East Cliff
• Most of Rufford's specimens are from
• Ecclesbourne Glen.
• Ashdown Beds Formation exposure at
• Ecclesbourne Glen is Berriasian

R2095
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A long-overdue closer look at the specimen
Left and right lateral
200 mm
Anterior
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A long-overdue closer look at the specimen
Anterior and posterior
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So what is it?
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So what is it? 1. Sauropoda
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So what is it? 2. Eusauropoda
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So what is it? 3. Neosauropoda
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So what is it? 4. a unique Neosauropod
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Similarities between sides
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Similarities and differences between sides
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Similarities and differences between sides
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Reconstruction
Parapophysis can be identified at junction
of laminae. Positions of diapophysis and
zygapophyses can be deduced from trajectories of
laminae. Condyle curvature inferred from
cotyle. High location of parapophysis indicates
posterior position.
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So what kind of Neosauropod is it?
Classic diplodocoids (Diplodocidae
Dicraeosauridae)
?
?
Diplodocoidea
Rebbachisauridae
Neosauropoda
Camarasauridae
Brachiosauridae
Macronaria
Titanosauria
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Is it a classic diplodocoid?
Diplodocus carnegii holotype CM 84, dorsal
8 (Hatcher 1901, Plate VII, reversed)
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Is it a classic diplodocoid?
Diplodocus carnegii holotype CM 84, dorsal
8 (Hatcher 1901, Plate VII, reversed)
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Is it a classic diplodocoid?
Diplodocus carnegii holotype CM 84, dorsal
8 (Hatcher 1901, Plate VII, reversed)
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Is it a rebbachisaur?
Rebbachisaurus garasbae holotype,
posterior dorsal (photo by Fabio Dalla Vecchia,
reversed)
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Is it a rebbachisaur?
Rebbachisaurus garasbae holotype,
posterior dorsal (photo by Fabio Dalla Vecchia,
reversed)
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Is it a rebbachisaur?
Rebbachisaurus garasbae holotype,
posterior dorsal (photo by Fabio Dalla Vecchia,
reversed)
Prezygapophyses close together
Laterally diverging prezygapophyses
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Is it a camarasaur?
Camarasaurus grandis holotype YPM 1901, posterior
dorsal (Ostrom McIntosh 1966, Plate 25)
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Is it a camarasaur?
Camarasaurus grandis holotype YPM 1901, posterior
dorsal (Ostrom McIntosh 1966, Plate 25)
Stupid and ugly
Stupid and ugly
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Is it a brachiosaur?
Brachiosaurus brancai holotype HMN SII,
D7 (Janensch 1950, Figure 56, reversed)
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Is it a brachiosaur?
Brachiosaurus brancai holotype HMN SII,
D7 (Janensch 1950, Figure 56, reversed)
?
?
?
?
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Is it a brachiosaur?
Brachiosaurus brancai holotype HMN SII,
D7 (Janensch 1950, Figure 56, reversed)
?
?
?
?
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Is it a titanosaur?
Neuquensaurus autralis MCS-5/20-22, D9 (Salgado
et al. 2005, Figure 4)
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Is it a titanosaur?
Neuquensaurus autralis MCS-5/20-22, D9 (Salgado
et al. 2005, Figure 4)
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Is it a titanosaur?
Neuquensaurus autralis MCS-5/20-22, D9 (Salgado
et al. 2005, Figure 4)
Internal structure camerate
Camellate
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So what is it?
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So what is it?
It seems to represent a completely new group (or
a very highly derived member of a known
group) ... what we used to call a new family
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How big was R2095?
Centrum proportions are similar to Brachiosaurus
brancai holotype HMN SII, D7 B. brancai is
estimated 25m long (Paul 1988) If isometrically
similar, R2095 would be 15m. B. brancai
is estimated 35000 kg (average of several
sensible published estimates). R2095
would be 7500 kg. (About the mass of a
big elephant)
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How big was R2095?
Longer and lighter if similar to Diplodocus
carnegii CM 84 D. carnegii is 27m long and 1200
kg (Wedel 2005). Centrum proportions differ,
so assume length proportional to centrum
length gt R2095 is 20m long assume mass
propotional to centrum length x cotyle height x
width gt R2095 masses 2300 kg
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Sauropods of the Hastings Beds Group
Humerus
Cetiosaurus brevis Pelorosaurus conybeari
(pending ICZN petition)
Pelorosaurus becklesi (actually generically
distinct and titanosaurian)
Humerus
Ulna
Radius
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Sauropod diversity goes nuts!
Dorsal vertebrae of Tendaguria tanzaniensis
holotype MB.R.2092.1-2, NB4, NB5 (Bonaparte,
Heinrich and Wild 2000)
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Sauropod diversity goes nuts!
Agustinia ligabuei Bonaparte 1999 Reconstruction
by Mudyryknow J.R., from The Dinosauricon http//d
ino.lm.com/images/display.php?id2268 It might
be some kind of titanosaur ...
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Sauropod diversity goes nuts!
Agustinia ligabuei Bonaparte 1999 Reconstruction
by Mudyryknow J.R., from The Dinosauricon http//d
ino.lm.com/images/display.php?id2268 It might
be some kind of titanosaur ... ... but
Titanosauria is the new Cetiosauridae
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Sauropod diversity goes nuts!
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I'd like to thank everyone who's made tonight
possible ...
My co-author Doctor Darren Naish Philip James
Rufford for finding and donating the specimen
Everyone who's ignored it for 113 years Sandra
D. Chapman (Natural History Museum) for access to
the specimen. Nick Pharris (University of
Michigan) for etymological assistance. We used
English translations of several papers from the
very useful Polyglot Paleontologist
web-site http//ravenel.si.edu/paleo/paleoglot/in
dex.cfm Thanks are due specifically to the
following translators Sebastián Apesteguía
(Bonaparte 1999a), Matthew T. Carrano
(Bonaparte 1986b), William R. Downs (Young and
Zhao 1972), Matthew C. Lamanna (Bonaparte and
Coria 1993, del Corro 1975 and Lavocat 1954)
Jeffrey A. Wilson (Salgado and Coria 1993). In
addition, portions of Janensch 1914 were
translated by Gerhard Maier. David M. Martill
(University of Portsmouth) reviewed the
manuscript. Mathew J. Wedel (UCMP) reviewed
this presentation.