Follow up trip to Sulphur, IN...Trilobite find

[JimTh]

Those of you with keener memories may remember that I posted about a trip to Sulphur, IN earlier this year.  After that trip, I've been wanting to get back pretty badly, dreaming of finding another shark tooth.  Columbus day and the cool weather got me back down there on Monday.

Like a trained dog, I headed right back to where I found the tooth before, knowing that it was improbable that I would find another. 

Within 30 minutes, I came up with this:

 

 

This appears to be a mostly present disarticulated trilobite.  Any ideas as to species?  My previous trilo tail was thought to be Paladins Chesterensis. This matches pretty closely to photos I can find of Paladins online.

I proceeded to find a couple more trilo tail fragments.  One was clearly just a small piece, so I left it.  Another might have more of the trilo embedded in the rock, so I brought it home.  It's tiny.

My next significant find was the biggest blastoid I've ever seen.  It outclasses my previous biggest by 1/4" in width.

 

As you can see, the part showing out of the rock is an inch wide point-to-point.  The rock it is embedded in is a bit thin, so it's possible that it's crushed/squashed out flat and wide, but the exposed portion doesn't show any breakage.  It may also just have the back side broken off.

I didn't find anything else real exciting.  I picked up some more of the dime sized blastoids, I just can't help myself. (I'm also thinking of sending them in to my son's kindergarten class.)  I also picked up a few 3d brachiopods, which you don't see a lot of at Sulphur.

I did see where someone else had slid down the slope from the shale layer...quite a ways.  The Sulphur site is not for the faint of heart.

[Raggedy Man]

That trilobite is better than any shark tooth you'll find there. Your initial identification is correct. Amazing find!

 

Best regards,

Paul

 

Paladin chesterensis (Weller and Weller, 1936)
Mississippian
Big Clifty Formation
Sulpher, Indiana, U.S.A.

[Raggedy Man]

I sent you some information on another site not too far from this one known to produce a fair amount of mississippian shark teeth as I get the feeling you're more interested in those. I have other sites close to that one as well. Let me know if you're interested as I'd be happy to share them with you in PM.

 

Best regards,

Paul

[Packy]

It looks like that trilo should be all there, with a little careful scraping. that area the matrix  usually is not to hard to remove. Nice find. I found a rock there last year with 2  next to each other, but one only a partial. Do not get it too wet, keep the glue handy, I am anxious to see how it cleans up.  That is one of my favorite sites. 

Packy

[piranha]

Paladin chesterensis is no longer valid.  The correct species is: Kaskia chesterensis

 

 

text from:

 

Brezinski, D.K. (2008)
Phylogenetics, systematics, paleoecology, and evolution of the trilobite genera Paladin and Kaskia from the United States.
Journal of Paleontology, 82(3):511-527

 

The difficulty of separating the plethora of apparently intermediate or ontogenetic morphologies resulted in a taxonomic conundrum that might be called the Paladin-Kaskia problem (Whittington, 1954). Morphologies exhibited by larger holaspid individuals of one species are observed in smaller individuals of different species assigned to these two genera. Traditional taxonomic methods confounded this problem by lumping intergrading morphologies of separate species into a single species, as well as combining groups of morphologically variable species into one genus, Paladin Weller, 1936. Through phylogenetic analysis, Brezinski (2003) demonstrated that 19 of the more widespread species assigned to Paladin from North America and Europe can be separated into four clades that spanned much of the middle and upper Carboniferous. The 11 North American species included in that analysis formed two distinct branches. Brezinski (2003) referred one branch to the genus Paladin and the other to a re-erected and re-diagnosed genus, Kaskia Weller, 1936. The success of the initial phylogenetic analysis prompted a more comprehensive evaluation of late Mississippian North American species, the results of which are reported herein. 

 

Since their erection by Weller (1936), Paladin and Kaskia have become consistently confused primarily, but not solely, because of insufficient diagnoses that were presented to separate the two taxa. This led to the synonomizing of the two genera so that all species were conveniently housed in the purported senior synonym Paladin.

[ynot]

Not a lot of finds - but they are really nice ones!

Tony