I found this possible plant fossil. I am hoping for an id. Accompanying this fossil are brachiopods and other marine fossils. This fossil came from the Otter Formation in central Montana. The Otter Formation is listed as an open and semi-restricted marine. This formation is Meramecian and Chesterian Mississippian.
The plant appears to be fibrous. No scale structure is present. In very fine sedimentary silty clay shale. These sediments capture fine details. I have included a photo of another fossil group of bryozoa to show the level of preservation of details.