Pentanogmius

[Ptychodus04]

Hi All,

In late June, early July of 2009, my friend and I spent 86 hours in a creek in Dallas County, Texas excavating what would turn out to be a special fossil. Temps were over 100 every day. The find was a large fish (over 5' long). Mid way through the excavation, we realized that what we were working on was a Pentanogmius sp. Thanks to Mike Everhart, we knew we were excavating the oldest Pentanogmius known, nearly 10 million years older than the oldest known. I spent 110 hours preparing the specimen. Here's a composite photo of the big boy. It will be donated to the Dallas Museum of Nature and Science right after the new year.

[2ynpigo]

Awesome fish!

Really a find of a lifetime. The museum should be grateful.

[jpc]

Now that is one heckuva cool fish. Good job on it. Do you have any field pix to share?

[Nandomas]

Great find and great prep work. Congrats... waiting to see some field pics :D I love them!

[Guest N.AL.hunter]

Congratulations and what a nice find!! I didn't even know you could find something like that in that area. Surely that site must have more than that one fish. Are you still working the site?

[Foshunter]

Awsome find, know what the heat in Texas is like, great prep. on the fish.--Tom

[Auspex]

Great Googly Moogly!

What a massive effort, and the results!

[BobWill]

Awesome catch, er find. Hope you consider a small ( or large ) presentation at DPS. I,m sure they would love to hear the story of your adventure!

Bob

[Fossildude19]

WOW!!! :wub:

Great job!

Thanks for showing it to us!

Regards,

[Xiphactinus]

Wonderful fish!!! Congrats on the find and the awesome prep work. I'd love to see some in-progress shots too!!

[tracer]

thanks for the effort you spent to make that fossil available for others to admire and study!

[Scylla]

Wow, what an effort. Thank you for the discovery AND for sharing it with us :bow: :bow:

[MikeD]

That's a beauty! Thanks for sharing.

[Tony Eaton]

A great find and even greater it is going to the museum!

[JohnJ]

Very, very cool! I can appreciate your efforts through lesser finds in similar conditions. Really well done.

[Ptychodus04]

As requested, here are a couple of in the field photos. I have some more, and am working on putting them on a page on my brand new web site. Once I get around to finishing the page, I'll post a link to all the photos. It really was an opportunity of a lifetime. The first photo is of me working on the head. BTW, the tail is down by my feet. This is the 2nd day of excavation. The second photo is of the Mr. Joe Fritsch, the discoverer, working on undercutting the slab that the fish is in. The third photo is of me jacketing the front 2' of the fish. We had already removed the caudal fin. It was fortunate that there were two natural cracks that we were able to use in sectioning the slab. The tail section was 40 pounds, the head section was around 400 pounds, and the middle section was around 700 pounds. Those were a lot easier to handle than around 1,200 pounds all at once!

[piranha]

Thanks Ptychodus04 for the great field photos. That really puts the effort into proper perspective. As amazing as the fish turned out seeing what you guys were up against with 1200 pounds of matrix in 100 degree heat make the incredible results that much more spectacular. Most of us will never have the chance to experience anything remotely similar in our fossil collecting pursuits so thanks again for giving us a look at what's actually going on to make it happen.

I have to tip my hat again to your amazing generosity. AWESOME!

[jpc]

Thanks... what's in the red bottle next to your head/elbow? Inquiring minds want to know.

[Shamalama]

Wow, so much work.... and you guys did it all for free! Who says non-professionals mess everything up? Thanks for the story and pics.

[Ptychodus04]

Thanks... what's in the red bottle next to your head/elbow? Inquiring minds want to know.

It's full of PVA (Polyvinyl Acetate). Fish fossils are notorious for starting to crumble once they are exposed. Their bones are made of many tiny layers of bone. Once they start to dry... they try to fall apart! Plus, the matrix was full of little cracks. I mix up the PVA at a 40:1 ratio with acetone. That makes it a little thinner than water. This allows the stabilizer to penetrate even damp fossils. It creates a little milky film on the surface (due to the water in the specimen) that is easily removed with straight acetone back in the prep lab.

PVA is usually dripped or brushed onto the bones. The syringe and bottle are leftovers from an antibiotic from one of my kids. It it works well for dropping small doses of PVA. Unfortunately, this bottle did not survive the excavation. It lost its life to a chisle tossed on it some time between 11:00 and 12:00 PM!!

[Ptychodus04]

So... this year's SVP meeting is here in Dallas. The below is a link to the meeting program and abstracts. Of special note is the abstract by Dr. Kenshu Shimada regarding the Pentanogmius specimen in this thread on page 213 (214 if you type in the page number).

http://vertpaleo.org/PDFS/39/39ad8cfa-19a3-4d99-a9fb-0dee66022922.pdf

:D :D :D :D

[kauai1800]

I was reading this thinking..."Kenshu Shimada...I swear I know him"...and in fact I do. I used to be on the faculty of DePaul Dept of Biological Sciences back in the day and worked with him pretty often (this was10 years ago or so).. Aloha Ken! Pretty fun to run into you here!

Edited September 17, 2015 by kauai1800

[Ptychodus04]

I was reading this thinking..."Kenshu Shimada...I swear I know him"...and in fact I do. I used to be on the faculty of DePaul Dept of Biological Sciences back in the day and worked with him pretty often (this was10 years ago or so).. Aloha Ken! Pretty fun to run into you here! - J. Patterson PhD

He's only here in spirit, unless he's lurking in the shadows. He has been studying several of my fish specimens or ones I have prepared for others.

[Ludwigia]

You must be one happy guy! The gears of time move slowly but steadily and precisely in the palaeontological world. Looks like your man did some very detailed studies on this specimen over the last couple of years once the prepping was done. Any photos of the finished product?

[Ptychodus04]

Roger, I am very excited. The amazing part of the story is that Dr. Shimada actually came to the Perot to look at another fish and saw ours!

Here are a couple photos of the fish at the Perot. Unfortunately, the company that built the display coated the whole thing with a ton of Butvar which caused it to lose the beautiful chocolate brown color of the bones. It was a necessary evil since the blocks (there were 3) were so unstable and fractured that the only thing holding them together were the plaster jackets. Oh well, it just smarts to have 18 months of your meticulous prep work covered up by a thick layer of plastic.