Tyrannosauroidea Osborn, 1905
lengi Hutt, Naish, Martill, Barker and Newbery 2001
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was much smaller than Tyrannosaurus but the skull, shoulder
and limbs were similar. The teeth in the premaxilla are D/U-shaped
in cross-section, with denticulations that continue over the tip
and the rostral carinae bear denticles for less than half the length
of the denticle-bearing part of the caudal carinae. There is a denticle
size difference index (DSDI) of c. 1.5, with between 13-20 denticles
per 5mm. The premaxilla is blunt with a vertical anterior border
and the maxilla is peculiar in that it has a posteriodorsally located
antorbital fossa border, with the part of the maxilla anterior to
this laterally flat. The nasals are fused.
manus is elongate and slender, with digit II nearly 95% the length
of the humerus, and has three well-developed metacarpals, and the
hindlimbs are gracile. The carpals not reduced to simple elements
as in tyrannosaurids.The humerus has a well-developed deltopectoral
crest and there are a series of internal hollows. The coracoid has
a prominent mediolaterally-wide, subcircular glenoid directed caudally,
but the coracoid foramen is absent. The scapulae have an expanded
dorsal end. The tibia is elongate with a weakly developed cnemial
crest (projecting process on the proximal part of the front surface
of the tibia, to which lower leg muscles are attached) and a robust
fibular crest. The cervical vertebrae are pleurocoelous, as is the
first sacral vertebra.
of element fusion elsewhere in the skeleton suggests that it is
a subadult, so it may be bigger than 4 metres in length. Numerous
character states are shared with tyrannosaurids, suggesting that
Eotyrannus is a basal tyrannosauroid and as such one of the
Material is rare, so please report it if you find some...
do I know if I've found a bone?