The brachiopod Isogramma Meek and Worthen (1870) is challenging to identify when found by inexperienced collectors. These fossils appear as a half circle of sharp, equal-spaced concentric growth lines. All specimens appear flattened, making their identification as a dimensional brachiopod shell difficult. The shells are concavo-convex in life, but dueRead More →

The monospecific genus Pennoceras has a limited range, the Brush Creek and Pine Creek limestones in Pennsylvania and Ohio. These curious members of the Goniatitida have a maximum diameter of only 37 mm. Miller and Unklesbay named these from specimens in the Carnegie Museum. My own specimen below is fromRead More →

I’ve been busy writing elsewhere, so the posts portion of this website is starting to age. Nevertheless, I have discovered several new things over the past few months, and I wanted to share at least one. I found a large specimen of a member of the Bellerophontidae, but in theRead More →

In the past, this gastropod was known as Bellerophon (Pharkidonotus). The name in parenthesis is due to subgenera naming. In modern gastropod taxonomy, several sub and super-names are used, including unranked groups that don’t fall into a classic hierarchy. McCoy named the family Bellerophontidae in 1852 in the publication “DescriptionRead More →

Poterioceras curtum is a Pennsylvanian cephalopod first described by Meek & Worthen in 1860. I originally misidentified these as Ctenobactrites isogramma. This is not the first report of this species in Western Pennsylvania. A report from the Annals of the Carnegie Museum in 1947 features specimens from the Brush CreekRead More →

Finding specimens of the paleozoic cephalopod genus Domatoceras in local rocks is difficult. They exist, but the genera Metacoceras and Pseudorthoceras dominate the cephalopod fauna. They are large cephalopods with a narrow venter. The younger whorls are only slightly or not impressed into the umbilical walls. Big shells are hardRead More →

While performing extensive research on the Paleozoic shark genus Petalodus, I uncovered many holotype specimens. Yet, in searching, there are still a couple that I have not been able to locate. Not finding some is not surprising, all the missing holotypes were described during the 19th century and the 1800s.Read More →