Pedicle valve (are those little holes Trypanites borings?)
The rest of the shell is imbedded in the rock so I have two profile views instead.
Left profile (I like the bryozoan epibonts that have colonized the exterior of the shell)
This specimen comes from the Ordovician ages limestones near St. Petersburg, Russia but the ID that was included with it is incorrect. I was told that it is a Clinambon sp. but a review of the Baltoscandian Fossils web site finds a completely different fossil. So I looked through the site's archives and found a possible match in Geniculina pseudoalternata. What do you think?