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Re: New Deinocheirus specimens found, indicating basal ornithomimosaur

Absolutely right, Tom. With the official paper not out yet, I couldn't use the 
images we saw at SVP. I recommended a photo of the holotype arms instead, but 
apparently the photo editor made a different choice. The new Deinocheirus looks 
drastically different.

- Brian 

Sent from my iPhone

> On Nov 4, 2013, at 6:43 PM, "Thomas R. Holtz, Jr." <tholtz@umd.edu> wrote:
> The illustration does NOT match the new discovery. Deinocheirus does not
> simply look like a larger, heavier Gallimimus.
>> On Mon, November 4, 2013 7:41 pm, Ben Creisler wrote:
>> From: Ben Creisler
>> bcreisler@gmail.com
>> For a much more detailed description of the find and the presentation
>> of the new Deinocheirus material, see Brian Switek's latest posting
>> for Laelaps:
>> http://news.nationalgeographic.com/news/2013/11/131104-dinosaur-hands-arms-body-mongolia/
>>> On Mon, Nov 4, 2013 at 10:21 AM, Ben Creisler <bcreisler@gmail.com> wrote:
>>> From: Ben Creisler
>>> bcreisler@gmail.com
>>> Now that the embargo on the SVP meeting abstracts has expired a number
>>> of notable items can be mentioned, pending formal scientific papers.
>>> Technical Session IX (Friday, November 1, 2013, 9:30 AM)
>>> LEE, Yuong-Nam, Korea Institute of Geoscience and Mineral Resources,
>>> Daejeon,
>>> Korea, Republic of (South); BARSBOLD, Rinchen, Paleontological Center,
>>> Ulaanbaatar,
>>> Mongolia; CURRIE, Philip, University of Alberta, Edmonton, AB, Canada;
>>> KOBAYASHI, Yoshitsugu, Hokkaido University Museum, Sapporo, Japan; LEE,
>>> Hang-
>>> Jae, Korea Institute of Geoscience and Mineral Resources, Daejeon,
>>> Korea, Republic of
>>> (South)
>>> The holotype of Deinocheirus mirificus was collected by the
>>> Polish-Mongolian Palaeontological Expedition at Altan Uul III in 1965.
>>> Because the holotype was known mainly on the basis of giant forelimbs
>>> with scapulocoracoids, Deinocheirus has remained one of the most
>>> mysterious dinosaurs. Two new specimens of Deinocheirus were
>>> discovered in the Nemegt Formation of Altan Uul IV in 2006 and Bugin
>>> Tsav in 2009 by members of the Korea-Mongolia International Dinosaur
>>> Expedition (KID). Except for the skull, middle dorsal and most of the
>>> distal caudal vertebrae, the right forelimb, left manus, and both
>>> pedes, the remaining parts of the skeleton (Mongolian Paleontological
>>> Center [MPC]-D 100/127) including a left forelimb clearly identifiable
>>> as Deinocheirus were collected. The humerus (993 mm in length) is
>>> longer than the 938 mm humerus of the holotype. The Altan Uul IV
>>> specimen (MPC-D 100/128) is a subadult Deinocheirus (approximately 72%
>>> of MPC-D 100/127), which consists of post-cervical vertebrae, ilia,
>>> ischia, and hind limbs. Both specimens provide important
>>> paleontological evidence for exact postcranial reconstruction of
>>> Deinocheirus mirificus. Cladistic analysis indicates that Deinocheirus
>>> is a basal member of Ornithomimosauria, but many new unique skeletal
>>> features appear to be quite different from other ornithomimosaurs.
>>> These include extreme pneumaticity of tall, anterodorsally oriented
>>> distal dorsal neural spines (7~8 times taller than centrum height)
>>> with basal webbing, fused sacral neural spines forming a midline plate
>>> of bone that extends dorsally up to 170% of the height of the ilium,
>>> ventrally keeled sacral centra, a well-developed iliotibialis flange,
>>> a posterodorsally projecting posterior iliac blade with a concave
>>> dorsal margin, a steeply raised anterior dorsal margin of the ilium,
>>> an anteriorly inclined brevis shelf, vertically well-separated iliac
>>> blades above the sacrum, an completely enclosed pubic obturator
>>> foramen, triangular pubic boot in distal view, vertical ridges on
>>> anterior and posterior edges of medial surface of the femoral head,
>>> and a robust femur that is longer than tibiotarsus. These features
>>> suggest that Deinocheirus (unlike other ornithomimosaurs) was not a
>>> fast-running animal, but a bulky animal with a heavily built pelvis
>>> and hind limbs. However, the dorsal ribs are tall and relatively
>>> straight, suggesting that the animal was narrow-bodied. A large number
>>> of gastroliths (>1100 ranging from 8 to 87 mm) were collected from the
>>> abdominal region of MPC-D 100/127, suggesting Deinocheirus was an
>>> herbivore.
>>> ==
> Thomas R. Holtz, Jr.
> Email: tholtz@umd.edu    Phone: 301-405-4084
> Office: Centreville 1216
> Senior Lecturer, Vertebrate Paleontology
> Dept. of Geology, University of Maryland
> http://www.geol.umd.edu/~tholtz/
> Fax: 301-314-9661
> Faculty Director, Science & Global Change Program, College Park Scholars
> http://www.geol.umd.edu/sgc
> Fax: 301-314-9843
> Mailing Address:    Thomas R. Holtz, Jr.
>            Department of Geology
>            Building 237, Room 1117
>            University of Maryland
>            College Park, MD 20742 USA