While reviewing all the fossils that I've written about from the Ludlowville and Moscow formations I realized that I'd never blogged about one of the most common fossils found in those rocks: Athyris spiriferoides. It's the most common fossil found along Lake Erie and is often found wave tossed and tumbled in the surf. It can be so abundant that in an hour of walking along the shoreline one can pick up two to three dozen specimens.
Here are three random specimens I picked up on my last trip to Lake Erie.
The three specimens show a size and shell shape range common to the species. At other localities the shell is much wider than long or they don't get this big. Some of the larger specimens will sometimes have a hollow cavity within filled with calcite. It's interesting to see that the shell is smooth for the most part until towards the edges where it shows some "flakes". I attribute that to the way the shell grew not as an result of erosion.
All three specimens came from the Wanakah Shale member of the Ludlowville formation along Lake Erie near 18 Mile Creek.