Other trilobites from wheeler formation

[Paleome]

Other trilobites I have found in the wheeler.

 

Asaphiscus wheeleri    Only one complete with impression.  Lots of fragments.  Note the huge, broad pygidium.

[Paleome]

Alokistocare harrisi, has been referred to as Altiocculus in the past.  Note how long and thin/pointy it is, with a very tiny pygidium.  I have a few other questionable trilobites, but I will post them later along this thread.    

 

One more Asaphiscus wheeleri, fractured.

[Huntonia]

That Alokistocare is killer!

[Tidgy's Dad]

Very nice trilobites.

And I agree, the Alokistocare is sensational. 

[FossilDAWG]

Very nice trilobites.

Just a note, I believe Alokistocare is the old name, and Altiocculus is the currently accepted name.

 

Don

[Paleome]

I really don't know the absolute current name.  Maybe someone can fill us in.  Tidgy's dad didn't comment on the name. If it were Altiocculus, the species name would be harrisi, I think. 

[Paleome]

Bolaspidella housensis?  It is kinda pointy like Alokistocare/Altiocculus, but the cephalon is proportionately larger to the thorax, compared to A. harrisi, and the trilobite, as a whole does not seem as elongate.  Next photo, impression of the same.

[Paleome]

Sorry, proposed B. housensis is 5mm long.  Same, or something else?  This one is 2mm long.

 

 

[Paleome]

Rather squat, huge cephalon.  Immature Elrathia? Next photo, I may need to prep this more, to find pygidium.   First one, 2mm long.  Second, 2.5mm long.

[Tidgy's Dad]

It does seem that Altiocculus harrisi is the correct name, my names are often out of date. 

You might be correct about the Bolaspidella, but we really need to ask someone who knows the Wheeler Shale formation or especially Scott @piranha, who is the go to guy for trilobites. 

[Paleome]

Ok, well this will be sitting here, for anyone to look at. Here are a few more, similar.  They are so tiny, 3mm and 1mm, I am thinking they could be juvenile, and haven't grown into their cephali to achieve their proper adult proportions, yet.

 

Sorry, the pictures are not the greatest.  That'said the best I can do for now.  I shall invite Piranha to also take a look.

[Tidgy's Dad]

Maybe this will help a little :

 

[FossilDAWG]

19 hours ago, Paleome said:

Bolaspidella housensis?  It is kinda pointy like Alokistocare/Altiocculus, but the cephalon is proportionately larger to the thorax, compared to A. harrisi, and the trilobite, as a whole does not seem as elongate.  Next photo, impression of the same.

Bolaspidella housensis has 15 thoracic segments, and Elrathia kingi has 13 segments.  See this link for the source, a thread by @piranha.  Proportions can change with growth, and also is strongly affected by how much the specimen is flattened during preservation, so you can't decide if a fossil is Bolaspidella or Elrathia based on how pointy the pygidium looks or if the cephalon seems broader.

 

Don

[piranha]

22 hours ago, Paleome said:

 

Altiocculus harrisi  has 32 thoracic segments.  

Instead, this specimen with approximately 24 segments matches better with Bolaspidella reesae.

 

 

Robison, R.A., Babcock, L.E. 2011
Systematics, paleobiology, and taphonomy of some exceptionally preserved trilobites from Cambrian Lagerstätten of Utah.
University of Kansas Paleontological Contributions, 5:1-47  PDF LINK

 

 

Bolaspidella housensis:

 

Robison, R.A. 1964

Late Middle Cambrian Faunas From Western Utah.

Journal of Paleontology, 38(3):510-566

 

 

Ontogeny Elrathia kingii:

 

 

Hopkins, M.J. 2020

Ontogeny of the trilobite Elrathia kingii (Meek) and comparison of growth rates between Elrathia kingii and Aulacopleura koninckii (Barrande).

Papers in Palaeontology (in press) 18 pp.

[Paleome]

That's what I suspected, an ontogeny issue.  Thanks all! 

[rocket]

On 8/16/2020 at 1:45 AM, piranha said:

 

Robison, R.A., Babcock, L.E. 2011
Systematics, paleobiology, and taphonomy of some exceptionally preserved trilobites from Cambrian Lagerstätten of Utah.
University of Kansas Paleontological Contributions, 5:1-47  PDF LINK

 

Bolaspidella housensis:

 

Robison, R.A. 1964

Late Middle Cambrian Faunas From Western Utah.

Journal of Paleontology, 38(3):510-566

 

 

Hopkins, M.J. 2020

Ontogeny of the trilobite Elrathia kingii (Meek) and comparison of growth rates between Elrathia kingii and Aulacopleura koninckii (Barrande).

Papers in Palaeontology (in press) 18 pp.

 

are these the best papers about the shale? We have a bulk of different trilos from there and I like to give them their names..., but, currently I go crazy with them 

 

 

Edited September 20, 2023 by rocket

[piranha]

4 hours ago, rocket said:

are these the best papers about the shale?

 

 

Those are just a few....there are many excellent papers on this topic:

 

 

Foster, J.R., Gaines, R.R. 2016
Taphonomy and Paleoecology of the "Middle" Cambrian (Series 3) Formations in Utah’s West Desert: Recent Finds and New Data.
Resources and Geology of Utah’s West Desert: Utah Geological Association Publication, 45:291-336  PDF LINK

 

Gunther, L.F., Gunther, V.G., Gunther, G. 1994
Some Middle Cambrian Fossils of Utah.
Brigham Young University Geology Studies, 28:1-87  PDF LINK

 

Hintze, L.F., Davis, F.D. 2003
Geology of Millard County, Utah.

Utah Geological and Mineralogical Survey, Bulletin 133:1-305  PDF LINK

 

Robison, R.A. 1964
Middle-Upper Cambrian Boundary in North America. 
Geological Society of America Bulletin, 75(10):987-993

 

Robison, R.A. 1964
Upper Middle Cambrian Stratigraphy of Western Utah. 
Geological Society of America Bulletin, 75(10):995-1010

 

Robison, R.A. 1971
Additional Middle Cambrian Trilobites from the Wheeler Shale of Utah.
Journal of Paleontology, 45(5):796-804

 

Robison, R.A. 1976
Middle Cambrian Trilobite Biostratigraphy of the Great Basin.

Paleontology and Depositional Environments: Cambrian of Western North America.
Brigham Young University Geology Studies, 23(2):93-109  PDF LINK

 

Robison, R.A. 1982
Some Middle Cambrian Agnostoid Trilobites from Western North America. 
Journal of Paleontology, 56(1):132-160

 

Robison, R.A., Babcock, L.E., Gunther, V.G. 2015
Exceptional Cambrian Fossils from Utah: A Window into the Age of Trilobites.
Utah Geological Survey Miscellaneous Publication, 15-1:1-97

[rocket]

1 hour ago, piranha said:

 

 

Those are just a few....there are many excellent papers on this topic:

 

 

Foster, J.R., Gaines, R.R. 2016
Taphonomy and Paleoecology of the "Middle" Cambrian (Series 3) Formations in Utah’s West Desert: Recent Finds and New Data.
Resources and Geology of Utah’s West Desert: Utah Geological Association Publication, 45:291-336  PDF LINK

 

Gunther, L.F., Gunther, V.G., Gunther, G. 1994
Some Middle Cambrian Fossils of Utah.
Brigham Young University Geology Studies, 28:1-87  PDF LINK

 

Hintze, L.F., Davis, F.D. 2003
Geology of Millard County, Utah.

Utah Geological and Mineralogical Survey, Bulletin 133:1-305  PDF LINK

 

Robison, R.A. 1964
Middle-Upper Cambrian Boundary in North America. 
Geological Society of America Bulletin, 75(10):987-993

 

Robison, R.A. 1964
Upper Middle Cambrian Stratigraphy of Western Utah. 
Geological Society of America Bulletin, 75(10):995-1010

 

Robison, R.A. 1971
Additional Middle Cambrian Trilobites from the Wheeler Shale of Utah.
Journal of Paleontology, 45(5):796-804

 

Robison, R.A. 1976
Middle Cambrian Trilobite Biostratigraphy of the Great Basin.

Paleontology and Depositional Environments: Cambrian of Western North America.
Brigham Young University Geology Studies, 23(2):93-109  PDF LINK

 

Robison, R.A. 1982
Some Middle Cambrian Agnostoid Trilobites from Western North America. 
Journal of Paleontology, 56(1):132-160

 

Robison, R.A., Babcock, L.E., Gunther, V.G. 2015
Exceptional Cambrian Fossils from Utah: A Window into the Age of Trilobites.
Utah Geological Survey Miscellaneous Publication, 15-1:1-97

wow, thanks a lot

thats enough to read for the next months...

Hope to find out what Trilos we have. Most I am sure I can find out, but I am really not deep familiar with Trilos