Gibbirhynchia amaltei brachiopod from France

This internal mold of a brachiopod is Gibbirhynchia amaltei from the Marginatus zone of the lower Jurassic (Pliensbachian). It comes from a site near Tournadous in the Aveyron region of southern France. The fossil looks like a Limonite replacement (or maybe lining) of the shell interior and retains just a small amount of the calcitic shell. The fossil is broadly ovate with valves that are mildly convex. When viewed from the front or back it looks somewhat flat or squat. Both valves have numerous and regular plications with a gentle fold and sulcus that is most evident along the anterior margins.

Brachial valve

Anterior

Pedicle valve (note the cast of the channel where the pedicle muscle would have been)

Anterior

Profile

Amaltheus sp. ammonite from France

Here is another type of pyritized Ammonite that can be found in the Toarcian aged rocks (Jurassic) around Millau, Aveyron Dept., France. It's labelled as an Amaltheus sp. and is a small fossil. The whorls overlap about 25% of each previous volution. The external ornamentation is preserved well with the strong ribs that do not continue onto the keel. The keel is smooth except for a raised portion that has slight notches regularly space so that it looks like a braid from the side. Not enough of the internal sutures are visible to tell for sure, but this specimen looks very similar to one that I saw on the Steinkern.de forum, in this post, that was identified as Amaltheus margaritatus cf. forma subnodosus.

Thanks to Gery for sending me this fossil!

Pseudogrammoceras fallaciosum ammonite from France

Here I have a nice pyritized specimen of the ammonite Pseudogrammoceras fallaciosum. from the Toarcian aged rocks (Jurassic) near Millau, Aveyron Department, France. The gently curving external ribbing has been preserved as has the complex internal suture pattern. Each volution of the whorl covers approximately 60% of the previous. The specimen is missing the living chamber.

Another view of the complex sutures.

Thanks to Gery for sending me this fossil!