Malcolmt Posted April 25, 2018 Share Posted April 25, 2018 Well I was fortunate to have the opportunity to collect with my fossil friend DevonianDigger and two others last week at Penn Dixie for a few hours. We probably moved about a ton of rock and who knows how much overburden. Jay was kind enough to share what he thought might be a promising spot even though he could only stay with us till noon. We pretty much had the site to ourselves so I was able to use the saw which helped us a lot in freeing out large blocks from the trilobite bearing layer. We got quite muddy as the water level at the site was fairly high. We in fact spent some time creating a drainage ditch to clear out the water from where we were digging. Between us we probably took out 60 potentially complete eldredgeops and perhaps 4 or 5 greenops and this little guy that I started to prep this morning. I knew this one had damage as the bug was in both the positive and the negative of the split. I was pretty sure in the field that it was not a greenops. I also have two presumed greenops I also found that are currently in glue up waiting prep. The prep starts out by reuniting the top and the bottom halves of the bug with cyanoacrylate glue that is clamped for 24 hours. Resist the urge to prep right away the glue bonds better if you let it cure 24 hours. Here is the first picture that I took just as the top of the eye is becoming exposed. Notice how I cut out the top piece and joined it to the bottom piece. You want to leave as little matrix on the top section as you can get away with because you do have to take it all of during the prep process. Here we are a little bit further. There is minimal scribe work being done it is all being done with 40 micron dolomite and a .015 COMCO nozzle on a COMCO MB1000 air abrasion unit at about 30 PSI. If I were to do much if any scribe work I would risk vibrating the glue bond loose and it would never glue back properly a 2nd time. Your first attempt at a join is always the best. Unfortunately I can already tell that there is some skin missing on the cephalon and that one of the genal spines is not there. After a bit more work So is it a greenops or a belacartwrightia More to come as the prep continues not counting gluing time we have about an hour invested in this bug. It is not a flawless bug by any means but is likely to be my first confirmed bela from Penn Dixie... I have prepped a couple of Bela's from there including a Fossil of the month here on the Forum ... but alas they were not mine...... 5 Link to comment Share on other sites More sharing options...
Kane Posted April 25, 2018 Share Posted April 25, 2018 Well done so far! I usually see these come out black, not brown, so this one is even more special. The fact that the eye is not blasted off makes this a very nice specimen. And thanks for the helpful tips on gluing halves together - it’s something I have no choice but to perform on a recent find. ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted April 25, 2018 Share Posted April 25, 2018 Very interesting and a most splendid bug! Thank you for sharing. Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
DevonianDigger Posted April 25, 2018 Share Posted April 25, 2018 Looking like a Greenops barberi based on the single row of pores on the plurae. But, that's a pretty wide margin on the cephalon. Need to see a little bit more body to make sure those pores don't go to two offset rows. But awesome bug!!! Glad you got some keepers! Jay A. Wollin Lead Fossil Educator - Penn Dixie Fossil Park and Nature Reserve Hamburg, New York, USA Link to comment Share on other sites More sharing options...
DevonianDigger Posted April 25, 2018 Share Posted April 25, 2018 I change my bet to Bellacartwrightia whiteleyi, I am willing to bet that those pores move to two rows further back. There's no way that margin is on a Greenops. Jay A. Wollin Lead Fossil Educator - Penn Dixie Fossil Park and Nature Reserve Hamburg, New York, USA Link to comment Share on other sites More sharing options...
Kane Posted April 25, 2018 Share Posted April 25, 2018 10 minutes ago, DevonianDigger said: Looking like a Greenops barberi based on the single row of pores on the plurae. But, that's a pretty wide margin on the cephalon. Need to see a little bit more body to make sure those pores don't go to two offset rows. But awesome bug!!! Glad you got some keepers! I didn't think any of the Greenops from PD were described yet. I know G. barberi and G. grabui are described outside of PD, though. That occipital spike keeps my bet on a Bella. The nodes should continue down the axis. ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
Malcolmt Posted April 25, 2018 Author Share Posted April 25, 2018 Well the fossil gods were not looking down on me on this one. There is a big chunk of the pleura missing on the right and the pygidium curls under and is broken off. Not sure that I will even continue to clean up any more at this point. I still think it is a bela. Here is another pic with the 2nd eye exposed... Disappointing but thems the breaks..... Link to comment Share on other sites More sharing options...
piranha Posted April 25, 2018 Share Posted April 25, 2018 55 minutes ago, DevonianDigger said: Looking like a Greenops barberi... Greenops barberi does not have a prominent occipital node. 42 minutes ago, Kane said: I didn't think any of the Greenops from PD were described yet. I know G. barberi and G. grabui are described outside of PD, though... Lieberman 1994 reports Greenops boothi from Penn Dixie: Lieberman, B.S. (1994) The evolution of the Hamilton Group fauna and a hierarchical perspective on evolutionary analysis. PhD Thesis, Columbia University, 949 pp. Lieberman & Kloc 1997 reports Greenops barberi from Penn Dixie: Lieberman, B.S., & Kloc, G.J. (1997) Evolutionary and biogeographic patterns in the Asteropyginae (Trilobita, Devonian) Delo, 1935. American Museum of Natural History Bulletin, 232:1-127 LINK 2 Link to comment Share on other sites More sharing options...
Malcolmt Posted April 25, 2018 Author Share Posted April 25, 2018 Definitely has a very prominent occipital node. Unfortunately everything after the cephalon was not so good..... but had two very nice eyes Link to comment Share on other sites More sharing options...
Kane Posted April 25, 2018 Share Posted April 25, 2018 18 minutes ago, piranha said: Lieberman 1994 reports Greenops boothi from Penn Dixie: Lieberman, B.S. (1994) The evolution of the Hamilton Group fauna and a hierarchical perspective on evolutionary analysis. PhD Thesis, Columbia University, 949 pp. Lieberman & Kloc 1997 reports Greenops barberi from Penn Dixie: Lieberman, B.S., & Kloc, G.J. (1997) Evolutionary and biogeographic patterns in the Asteropyginae (Trilobita, Devonian) Delo, 1935. American Museum of Natural History Bulletin, 232:1-127 LINK (My sources were well out of date! - Doh!) - Thanks for the correction. ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
DevonianDigger Posted April 25, 2018 Share Posted April 25, 2018 Didn't see the node at first glance. Jay A. Wollin Lead Fossil Educator - Penn Dixie Fossil Park and Nature Reserve Hamburg, New York, USA Link to comment Share on other sites More sharing options...
MeargleSchmeargl Posted April 26, 2018 Share Posted April 26, 2018 That's a bummer. But hey, take what you can get. Every single fossil you see is a miracle set in stone, and should be treated as such. Link to comment Share on other sites More sharing options...
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