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© 2010 Dinosauria International Ten Sleep Report Series No. 1
A
B
C
Fig 16 A. posterior caudals with associated chevrons terminating in an unusual pathology displaying bone overgrowth in DQ-SB.
B. close up of the left side. C. close up view of right side of terminal caudal.
the actual specimen could not be examined while in plaster
jackets. All five specimens are, at present, in various states
of preparation and cannot be described individually in
more detail at this time. Many of the photographs presented
here reflect these various states. What follows is, therefore,
a preliminary description from a work-in-progress. Future
reports are planned which will include complete descriptions
with comparisons of and new specimens. Also planned is a
phylogenetic study incorporating cladistic methodology.
DQ-BS = “Brontodiplodocus”, Table 1, Figs: 1, 5 - 8, 19, and
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This specimen marks the first skeleton to be found
with a skull preserved intact and articulated to a nearly
complete series of cervical vertebrae. The skull, lower jaws,
and the five cervical vertebrae complete with ribs are kept in
situ in the original matrix block. The skeleton is estimated
to be 80-90% complete, and the free-standing mount is 24.68
m. (81 feet) in length, in contrast the reconstructed skull
is approximately 36 cm (14.17 inches) long. Preliminary
observations suggest the individual was a young adult when
it died. However, the exact age of this individual is under
investigation at the Division of Paleontology, American
Museum of Natural History. This study will rely on taking a
thin section of sclerotic bone for dating, a first for sauropod
paleobiology.
The intact skull displays all the delicate cranial bones
largely without distortion (Figs. 4 & 5). Although displaced,
even the fragile sclerotic bones are preserved complete in
their orbital cavity. The pear shaped orbital opening is
relatively large and extends anterior-ventrally with a slight
constriction located at the anterior margin created by a bulge
on the lacrimal. The extended shape of the orbit is in some
ways reminiscent of the condition present in large derived
theropods (Chure 1998). The lower jaws are preserved
articulated. Only the premaxillae were displaced during
excavation and cannot be seen in the accompanying photo.
In addition to the orbit and nasal openings, the preantorbital,
antorbital, supratemporal, and lateral temporal fenestrae
are all complete and without distortion. The interfenestra
bridge (Witmer 1997) dividing the preantorbital from the
antorbital fenestrae is well preserved. Resting above the
occipital condyle are the small and rarely found proatlas
bones, which are preserved in situ along with the atlas.
The occipital condyle is ventrally positioned nearly at a
right angle to the long axis of the skull, as in all Morrison
diplodocids. Numerous teeth are scattered in the matrix
block preserving the skull. The crown of an unworn tooth
is slightly compressed labial-lingual and tapers towards the
apex with an outline that is narrow spatulate. A slight lingual
curve exists on the crown and on that surface a faint ridge
running down its length is discernable. The root is nearly
cylindrical in cross section.
Every bony process, spine, and rib along the
cervical series is preserved on the thirteen vertebrae that
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