Greenops widderensis

Actually, Greenops in the Widder are quite common.  What is uncommon is to find them whole and intact like this one you've posted here! The Widder shale is absolutely littered with disarticulated bits. You can go through tons of shale before finding a half decent whole one.

@Kane yes that's what I meant. It seems like if you wanted to find a decent Greenops you would go to Arkona because they are definitely there from what I've heard but difficult to find intact. Seems like the Penn Dixie shale is more dense and able to preserve these fossils better. I really like the one you recovered and hopefully you will post it to Collections.

You have that right! Although Greenops are not exactly easy to find in PD, it is definitely a more forgiving shale, but also the conditions of the initial deposition differ, which accounts for why the Widder has beaucoup de bits! Here's a picture of a pretty standard Widder shale:

 Well there is a lot in there!  I suppose this goes back to our earlier  discussion of the density of mud and sand during burial.  So why are there more specimens located there as opposed to New York? 

Just now, Fossil-Hound said:

 Well there is a lot in there!  I suppose this goes back to our earlier  discussion of the density of mud and sand during burial.  So why are there more specimens located there as opposed to New York? 

That's a good question. I'm not entirely sure! It might be a difference in sea levels, available food, different levels of competition or predation... I'd have to look into it more! (Or I could just say that it's a Canadian thing  ). I do know one big difference between the Widder and the Windom is that the latter generally have slightly smaller E. rana. Also, the brach species are quite different.

But one thing you might want to do just for fun is to compare your G. widderensis with any G. barberi you pulled from PD. The differences may be slight, but perhaps interesting nonetheless!

29 minutes ago, Kane said:

That's a good question. I'm not entirely sure! It might be a difference in sea levels, available food, different levels of competition or predation... I'd have to look into it more! (Or I could just say that it's a Canadian thing  ). I do know one big difference between the Widder and the Windom is that the latter generally have slightly smaller E. rana. Also, the brach species are quite different.

 

But one thing you might want to do just for fun is to compare your G. widderensis with any G. barberi you pulled from PD. The differences may be slight, but perhaps interesting nonetheless!

 That's a good idea. I think I only have one and it's not the best specimen for comparison.  Suppose I could compare it with the Bellacartwrightia since they are similar in origin.  Reading through Trilobites of New York is a lot of fun  because they're little subtle differences in the species.  @DevonianDigger just sent me a text with one he found a few days ago on the ground!  I will have to pester him into posting it so we can do more comparisons.

Late contributing. I was fortunate enough to get to spend an afternoon with @GerryK (Gerry Kloc) at his office at U of R, while I was there he was telling me that the Greenops sp. at Penn Dixie are technically yet-to-be-described. That being said, I'm keeping my eyes out for PD Greenops in the hopes that I can collect enough to contribute to a proper classification at some point. If you guys want to send me good photos of any that you've collected there that might be complete, I would love to start a catalog of photos to refer to!

I suspect that the collections of pygidiums we find at Arkona are most likely molts that then collect together because they are the same size and shape when deposited by the current.

On 6/21/2017 at 3:54 PM, DevonianDigger said:

Late contributing. I was fortunate enough to get to spend an afternoon with @GerryK (Gerry Kloc) at his office at U of R, while I was there he was telling me that the Greenops sp. at Penn Dixie are technically yet-to-be-described. That being said, I'm keeping my eyes out for PD Greenops in the hopes that I can collect enough to contribute to a proper classification at some point. If you guys want to send me good photos of any that you've collected there that might be complete, I would love to start a catalog of photos to refer to!

@Malcolmt just prepared one for a gentlemen and that particular Greenops is in the IPFOTM contest for September.