minnbuckeye Posted February 8, 2018 Share Posted February 8, 2018 I am finally getting most of my trilobite parts identified but still need some schooling on this pygidium: It was found in the Platteville/ Ordovician in SW Wisconsin. It is 4cm by 4.5 cm In addition, these two plates contain what I thought were just pieces of Isotelus, but the more I looked, the more I questioned my thoughts. Agree or change the ID? These plates are 12 inches by 6 inches. The asterisk's mark where the specimens are. Link to comment Share on other sites More sharing options...
minnbuckeye Posted February 8, 2018 Author Share Posted February 8, 2018 Another similar piece. Finally, this to ID Link to comment Share on other sites More sharing options...
Fossildude19 Posted February 8, 2018 Share Posted February 8, 2018 Your last picture looks like a Hypostome. Not familiar with this shape though. @piranha may help. Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
piranha Posted February 8, 2018 Share Posted February 8, 2018 The pygidium is Isotelus simplex. The cranidium next to the cheirurid is: Raymondites longispinus Swisher, R.E., Westrop, S.R., & Amati, L. (2015) The Upper Ordovician trilobite Raymondites Sinclair, 1944 in North America. Journal of Paleontology, 89(1):110-134 PDF LINK 3 Link to comment Share on other sites More sharing options...
Herb Posted February 9, 2018 Share Posted February 9, 2018 Looks like Isotelus sp to me also. "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
minnbuckeye Posted February 9, 2018 Author Share Posted February 9, 2018 Thanks @piranha. I am not familiar with this Isotelus. Here is the pygidiums that I usually find: Link to comment Share on other sites More sharing options...
piranha Posted February 9, 2018 Share Posted February 9, 2018 2 hours ago, minnbuckeye said: Thanks @piranha. I am not familiar with this Isotelus. The pygidium of Isotelus simplex is more inflated and does not have an obvious axial lobe. Compare with these examples posted over the years on TFF: Failleana indeterminata could also be a possibility from the Platteville Formation. With the specimen in hand you can determine which one is the best match. 2 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now