Lambeosaur (Hypacrosaurus) Ulna & Radius with Metal Stand - Montana

This is an awesome radius and ulna of a Hadrosaur (Hypacrosaurus sp.), collected from the Two Medicine Formation of Montana. The bones were collected this last summer and have been nicely prepared from the hard rock surrounding them. They comes with a custom metal display stand that holds the bones in position.

The bones were found fractured and fragmented within the rock, each of which required crack repair and gap fill restoration. The proximal end of the ulna required the most restoration, with the majority of the restoration in the form of gap fill where the bone crumbled away. Crack repair and glue stabilization continues through the diaphysis of the bone. The cracks with significant gap fill restoration are closest to the distal end of the bone. While the distal end of the ulna is weathered, there is no indication of any repair or restoration.

The radius has the least amount of restoration of the two bones, with most in the form of gap fill in repaired cracks. These repaired cracks are centralized throughout the diaphysis of the bone. The striated appearance of the bone can be attributed to geologic forces that resulted in countless fractures. The proximal and distal ends are weathered and each required crack repair along the same edge.

Measurments:
Ulna - 19.7" long
Radius - 19.2" long
Bones and stand - 22.4" tall

Comes with the pictured custom metal display stand.

Hypacrosaurus is a very large, Lambeosaurini Hadrsosaur that would have been almost as large as the Tyrannosaurs that it lived alongside. Like Corythosaurus, it had a tall, hollow rounded crest, although not as large and straight. It is known from the remains of two species that spanned 75 to 67 million years ago, in the Late Cretaceous of Alberta, Canada, and Montana, United States, and is the latest hollow-crested duckbill known from good remains in North America. It is estimated to have been around 9.1 meters (30 feet) long and to have weighed up to 4-5 tons.

 Hypacrosaurus drawing by wikipedia user debivort. Creative Commons License
Hypacrosaurus drawing by wikipedia user debivort. Creative Commons License

The Two Medicine Formation is a geographical formation in Central Montana and Southern Alberta, Canada. The formation is predominantly sandstone laid down by rivers and deltas during the Campanian Age of the Cretaceous about 80-75 million years ago. Approximately two thousand feet thick on the western edge, it lies on top of the Virgelle Sandstone formation and under the Bearpaw Shale. It is located between the Front Range of the Rocky Mountains and the Sweetgrass Arch, a tectonic fold feature 40-90 miles east of the Front Range.

The Two Medicine is the same age as the Judith River Formation found further east. It was laid down further inland from the Western Interior Seaway, while the Judith River Formation was deposited along the coast. The Two Medicine contains much of the same dinosaur fauna, but fewer reptiles, amphibians and aquatic fossils.

A view of the Two Medicine Formation quarry operated by Northwest Montana Fossils where much of our Two Medicine dinosaur material has been found.
A view of the Two Medicine Formation quarry operated by Northwest Montana Fossils where much of our Two Medicine dinosaur material has been found.

DETAILS
SPECIES
Hypacrosaurus sp.
LOCATION
Pondera County, Montana
FORMATION
Two Medicine Formation
SIZE
Height on Stand: 22.4" tall
CATEGORY
SUB CATEGORY
ITEM
#192749
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