Fossil Mountain, Millard County, Utah, Trilobites

[LabRatKing]

Hi gang, 

 

I'm working fervently to prepare a post about the astounding time I had at Fossil Mountain in Utah during my fossil run back in July. (Will take me months to process and identify all these samples from four states.)

 

I found a few partial trilobites at the upper layer of the Lehman formation, but I'm having difficulty identifying them. I freely admit I'm exceedingly weak at trilobites ID.

 

these aren't the best pictures or even the best specimens, but I was there solo and the scree around the cliffs was pretty unstable so I erred in the side of caution. 

 

Anyway, Any suggestions much appreciated.

 

I'll post better pictures tomorrow when I get my camera back off of my microscope at work.

[caldigger]

@ynot, @Fossil-Hound, @piranha

[ynot]

I got nothing on these.

[piranha]

This one is a lower Ordovician pliomerid similar to: Cybelopsis sp.

 

 

Hintze, L.F. 1952

Lower Ordovician Trilobites from Western Utah and Eastern Nevada.

Utah Geological and Mineralogical Survey Bulletin, 48:1-249

[LabRatKing]

Perfect! Thanks! I'll dig this paper up today.

 

I have three pygidia and one cephalon of the other. However the depth is in substrate and upside down. It's going to be difficult to expose.

 

[piranha]

Please post a clear photo of this one:

[Fossil-Hound]

On 8/15/2019 at 3:41 AM, piranha said:

This one is a lower Ordovician pliomerid similar to: Cybelopsis sp.

 

 

Hintze, L.F. 1952

Lower Ordovician Trilobites from Western Utah and Eastern Nevada.

Utah Geological and Mineralogical Survey Bulletin, 48:1-249

@LabRatKing this could be Kanoshia kanoshensis though the image you have is a little blurry. Here's a wikipedia entry with a pygidium I found a few years ago:

 

https://en.wikipedia.org/wiki/Kanoshia

 

That particular location doesn't preserve trilobites very well because it was a high energy deposition (high current). I have yet to find a complete trilobite from that location.

[piranha]

24 minutes ago, Fossil-Hound said:

...this could be Kanoshia kanoshensis though the image you have is a little blurry...

 

 

Cybelopsis is a better match.  Compare the the axial ring furrows and the terminal axial piece.  Kanoshia has uninterrupted axial ring furrows and a smaller terminal axial piece.

 

                                                                                                                                                                                               

[Fossil-Hound]

10 hours ago, piranha said:

 

 

Cybelopsis is a better match.  Compare the the axial ring furrows and the terminal axial piece.  Kanoshia has uninterrupted axial ring furrows and a smaller terminal axial piece.

 

                                                                                                                                                                                               

Wouldn't the two be related? Have you ever seen a complete Kanoshia? I've never seen one.

[piranha]

1 hour ago, Fossil-Hound said:

Wouldn't the two be related? Have you ever seen a complete Kanoshia? I've never seen one.

 

 

Yes, they are both pliomerids.  Here is a complete Kanoshia kanoshensis.

 

[Fossil-Hound]

On 8/21/2019 at 11:32 PM, piranha said:

 

 

Yes, they are both pliomerids.  Here is a complete Kanoshia kanoshensis.

 

Wow that's gorgeous. From Millard Co.? Did you find this one? I have yet to find one as that area was volatile and doesn't preserve fossils very well. Maybe someday I'll get lucky.