488.3 to 251.3 MYA

Scientific Classification














de Montfort 1808

Catalog Number: CG-0106

The genus Bellerophon is chock full of different species. This particular specimen was found in the soft punky later over top of the limestone, right after I found a specimen of Pulchratia. I often find pieces of these, however nothing with detailed ornamentation like this example.

Next I will have to determine the species. The Fossilworks website lists approximately 126 named species for Bellerophon. One avenue is to check local research from the Glenshaw formation or regional research from the Brush Creek Limestone and see if any have been reported with illustrations or photographs.

P. D. de Montfort’s Illustration from 1808

In 1808 at the age of 42, Pierre Denys de Montfort published what is known at the first written report of the genus. His publication, Conchyliologie systématique, et classification méthodique des coquilles (Systematic conchology, and methodical classification of shells) was an attempt at classification of shells. He calls this conchology, which appears to be an antiquated term in modern times. Interestingly, this was during the reign of Napoleon Bonaparte.

An illustration accompanies the listing, showing a wound shell that appears wider than my example. However, with this genus having so many different species, it’s likely correct. In his opening description, it calls it a shell rolled upon itself with a “very oval mouth”. This is very fitting.

Generic characters. Shell free, univalve, septate, rolled on itself and in a depressed spiral, forming the shuttle; the last turn containing all the others; very oval mouth, receiving in its middle the back of the shell j united partitions, pierced by a siphon.

Translated into English from P. D. de Montfort. 1808. Conchyliologie systématique, et classification méthodique des coquilles, Page 51

But it looks like a Cephalopod

That is quite true. It has the same coiled shell that a cephalopod possesses. With the fine ornamentation, I even considered this was an Ammonoid, but this appears to be very much a gastropod. Cephalopod’s have sections or septa in their shells which the fill with gasses in order to float. A gastropod shell is just hollow all the way through. They don’t close off sections of shell as it grows.

A long lived genus

Going by the numbers on Fossilworks, the first examples of Bellerophon appear in the late Cambrian. It died out shortly after the Permian-Triassic Extinction, in the Early Triassic period. This equals over 235 million years of time. From today, back to 500 million years ago, this little sea snail lived through about half of that time.

Temporal range of the Genus Bellerophon
Focus stacked view of specimen CG-0106
Focus stacked view of specimen CG-0106