Pennsylvanian trilobite ID

[KCMOfossil]

I was going through my trilobite pygidiums and cephalons from the Winterset of the Pennsylvanian Kansas City group and I found this cephalon that seems different from the others I have.  In particular, the genal spine seems curved.  In the photos you can see both the internal mold and, in the other half of the split, the inside of the shell.  I assume the pygidium beside it is belongs to the same creature, but I could be wrong.  Any help with the ID will be appreciated.

 

Russ

 

 

 

[KCMOfossil]

Two more pictures.

[piranha]

The key features of the glabella match well with: Ameura missouriensis

 

 

Moore, R.C. (ed.) 1959

Treatise on Invertebrate Paleontology. Part O. Arthopoda 1. Trilobita.

Geological Society of America and University of Kansas Press, 560 pp.

[KCMOfossil]

10 hours ago, piranha said:

The key features of the glabella match well with: Ameura missouriensis

Thanks, piranha.  What confused me was the shape of the genal spine.  But I can see from the drawing by Moore that what I'm seeing is just the top of the spine.  I have Moore's 1952 book, Invertebrate Fossils but the Ameura drawing in it is not so clear.   I keep learning.  I would like a better resource of drawings and photos for the trilobites of the Pennsylvanian, and I see Moore is available on the auction site.  Anyway, thanks again.

 

Russ

 

[Jackson g]

Nice find, the closest I've got is just a single Ameura pygidium. If you ever find one complete please share it!

[KCMOfossil]

On 9/6/2020 at 8:51 AM, Jackson g said:

Nice find, the closest I've got is just a single Ameura pygidium. If you ever find one complete please share it!

I've been hoping for a complete one someday, but nothing so far.  Others have found them at times in our area, but I guess we'll just have to keep looking.  Happy hunting!

 

Russ