Views of the Mahantango: Pholidostrophia from Sylvania, OH

Pholidostrophia is a brachiopod that I was introduced to in the rocks along the Lake Erie shore at Eighteen Mile Creek. You can read those post by clicking here and another post of specimens from my local Mahantango formation here. Below are two specimens from the Silica Shale of Sylvania, Ohio that I collected a few years ago. It's interesting to compare the specimens from the similarly aged Mahantango formation and Wanakah Shale to these. The Silica Shale specimens are larger than those from the other two localities. This same feature seems to occur in many of the Brachiopod genera that are found in the Silica Shale and could be due to a calmer, more food rich environment in which they lived.

I'm going to call these Pholidostrophia geniculata based on the 1975 book by Robert V. Kesling & Ruth B. Chilman: Strata and Megafossils of the Middle Devonian Silica Formation: Museum of Paleontology, Papers on Paleontology, No. 8, pg. 100, pl. 118.

Pedicle Valve