Hadean Fossilized Dragon Brain or Cephalopods?

[Lucid_Bot]

I'm chipping away at what I think is brush creek limestone to find what I think is Mooreoceras (first two pics) and Metacoceras. I have no idea what the last fossil is. All help is appreciated, thank you.

[connorp]

The last one is a productid brachiopod.

@cngodles

[cngodles]

Kröger and Mapes (2005) determined that Mooreoceras is now a discontinued genus. There has long been a debate between Pseudorthoceras and Mooreoceras, whereas researchers considered the former to be the younger part of the latter. They studied a large number (n = 196) of OSU specimens and found no discernable morphometric difference between the two aside from size and siphuncle position, but it did start to vary as Pseudorthoceras got larger.

 

The cephalopod can be labeled as Pseudorthoceras sp, likely Pseudorthoceras knoxense. The pair called it the "characteristic orthocerid of the Carboniferous in general".

 

As for the brachiopod, these are plano-convex types of shells. The pedical valve is convex and the brachial valve is flat or concave (if so, it's concavo-convex). They look odd because they are a flat and small, and you are looking at the inside of the shell (brachial valve). The other side (pedical valve and outside), looks like this:

 

 

Edited July 19, 2022 by cngodles
siphuncle