Mystery Gastropod Fossils from Romania

Salut! These pictures show gastropod fossils found in Romania. They are from a region that use to be the Sarmatic Sea which I think is Miocene in age (5-7 million years ago).

What their names are is a mystery to me.  So if there are any fossil detectives out there and you can solve this naming enigma... let me know. Mulţumesc!

Thanks to Stanca for the pictures.

Cornulites proprius on a Platystoma Fossil

Pictured are several Silurian Waldron Shale fossils. It appears to be the fossilized habitat of a Cornulites proprius attached to the gastropod Platyostoma niagarense. This ensemble was found in Clark County, Indiana. While snail/worm fossil combos are found quite a bit in the Shelby County, Indiana, my experience is they are not quite as common in the more southern county of Clark in Indiana.

Fossils have not been prepped yet so I am hoping for better detail once they are cleaned.

Pyrite/Marcasite Silurian Fossils

All these fossils were found in the Waldron Shale of Clark County, Indiana. All contain pyrite or marcasite minerals. These first two pictures show the iron sulfide clusters embedded in a Silurian Period brachiopod Homoespirifer evax.

 The next two pictures show a segment of byrozoan encrusted with pyrite.

The last two pictures do not this fossil pairing justice. It is a crinoid stem that has another crinoid holdfast wrapped around the stem. Both are encrusted with pyrite or marcasite. A nice photo of one these crinoid ensembles at the Falls of the Ohio State Park web site: CLICK HERE.