3.4" Fossil Ceratopsian (Achelosaur) Caudal Vertebra - Montana

 
 
 
This is a 3.4" Ceratopsian (Achelosaur) caudal (tail) vertebra from the Two Medicine Formation of Montana.

There are repaired cracks with some minor gap fill restoration through the pedicles. The centrum is missing a section of bone along one edge, though there is no repair or restoration. A neat feature of this specimen is the vertebral arch that remained intact through the preservation process. The rock it was found in has been left within the vertebral foramen to ensure structural integrity.

Comes with the pictured metal display stand.


Ceratopsians are a group of plant-eating dinosaurs from the Cretaceous characterized by a bony frill on the back of the skull and a unique upper beak bone, called a rostral. Ceratopsians ranged in size from 1 meter (3 ft) and 23 kilograms (50 lb) to over 9 meters (30 ft) and 9,100 kg (20,100 lb). Triceratops is by far the best-known ceratopsian to the general public.

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.
FOR SALE
$495
DETAILS
SPECIES
Achelosaur sp.
LOCATION
Pondera County, Montana
FORMATION
Two Medicine Formation
SIZE
3.4 x 2.8", 4.4" tall on stand
CATEGORY
SUB CATEGORY
ITEM
#148795
GUARANTEE
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