Norwood and Pratten first described Antiquatonia portlockiana in 1855 as Producti portlockianus. In 1976, the species was rearranged as Antiquatonia portlockiana by Douglas C. Brew and Stanley S. Beus.
Specimens of Antiquatonia Portlockiana from Armstrong County
Brachiopods have been a less-than-common find at the Pine Creek locality. Gastropods, Cephalopods, and Rugose Corals are the most common. Larger brachiopods are even more challenging to find. However, there is typically exceptional shell preservation when they do show up. The two specimens below are above average in preservation. In the Brush Creek limestone, normally, you lose an outer shell layer, and the ears break off.
- 1855, Norwood, J.G., Pratten, H., Notice of fossils from the Carboniferous Series of the western states belonging to the genera Spirifer, Bellerophon, Pleurotomaria, Macrocheilus, Natica, and Loxonema, with descriptions of eight new characteristic species. Journal of the Academy of Natural Sciences of Philadelphia 3: pp. 71-77
- 1976, Brew, D.C., Beus, S.S., A Middle Pennsylvanian fauna from the Naco Formation near Kohl Ranch, Central Arizona. Journal of Paleontology 50, pp. 888-906