Kope Formation Trilobite ID

[connorp]

I found this very fragmentary trilobite cephalon in the Upper Ordovician Kope Formation in Kentucky that I am unsure of. Not much to go on, but I was hoping someone here might recognize it. Any thoughts are appreciated.

 

 

[RCFossils]

I think this might be Achatella carleyi.

I am not sure if they are known from the Kope but are found in the Fairview (rare).

[Fossildude19]

@piranha

[connorp]

4 hours ago, RCFossils said:

I think this might be Achatella carleyi.

I am not sure if they are known from the Kope but are found in the Fairview (rare).

Thanks for the suggestion. I found a description of the outcrop and it passes through the Kope/Fairview contact, so I could have been collecting in the Fairview. I still have trouble differentiating the two formations.

[piranha]

Achatella carleyi  is now also reported from the base of the Kope Formation:

 

"New sclerites of A. carleyi were collected from older strata of the Fulton Submember at the base of the Kope Formation (Datillo et al., 2008, fig. 2) at the Blue Licks locality in northern Kentucky (see Bulinski 2007). This new material is fragmentary and generally poorly preserved; it adds no new information on anatomy of the species and is not illustrated. However, they provide important data on stratigraphic occurrence and extend the range of A. carleyi down to the lower part of sequence C1."

 

text from:

 

Swisher, R.E., Westrop, S.R., Amati, L. 2016

Systematics and Paleobiogeographic Significance of the Upper Ordovician Pterygometopine Trilobite Achatella Delo, 1935.

Journal of Paleontology, 90(1):59-77

 

Bulinski, K.V. 2007

Analysis of Sample-Level Properties along a Paleoenvironmental Gradient: The Behavior of Evenness as a Function of Sample Size.

Palaeogeography, Palaeoclimatology, Palaeoecology, 253(3-4):490-508

 

 

fig. 2 chart from:

 

Datillo, B.F., Brett, C.E., Tsujita, C.J., Fairhurst, R. 2008

Sediment Supply versus Storm Winnowing in the Development of Muddy and Shelly Interbeds from the Upper Ordovician of the Cincinnati Region, USA.

Canadian Journal of Earth Sciences, 45(2):243-265