This is a partial fossil of a type of Pelecypod called a Rostroconch. I'm not entirely sure of the genera but it could be Conocardium or Hippocardium. The fossil was found in some dumped dolostone that came from the quarries in Sylvania. Based on the stratigraphy of the area, the depths of the quarries and a description of the formations I believe this came from the Lucas Dolomite (1).
This is the first Rostroconch I've found. I first saw one on Mike's blog, Louisville Fossils, where he found one from the Jeffersonville Limestone.
(1) G. M. Ehlers, E. C. Stumm and R. V. Kesling - "Devonian Rocks of Southeastern Michigan and Northwestern Ohio". 1951