First Peace River trip of the season--December 2016

[Harry Pristis]

I don't think this is a horse incisor, nor is it like any dugongid tooth I've ever seen.  Ask Hulbert about it.

[digit]

Dropped some photos of my mystery cookie to Dr. Richard Hulbert for his opinion on the Tortoise or Glyptotherium origin of this little mystery. He says he'll show it to some others up at FLMNH but his initial opinion is that a glyptodont tail armor osteoderm should show more markings where it interfaced with adjacent osteoderms. Having said that he did say that the under surface seemed oddly pockmarked for a normal tortoise osteoderm (but I wonder if that is the result of wear and tear from the river). Jury is still out on this but I'll try to remember to bring it when I go up to volunteer at Montbrook (hopefully, sometime soon).

 

I looked back through my past finds and came up with another specimen nearly identical to this so whatever it is I have at least two of them.

 

Cheers.

 

-Ken

 

   

 

   

[Cris]

Those osteroderms are giant tortoise. I have sites that produce an abundance of giant tortoise material and I've found a few dozen or so in those sites that look identical (I can snap some pics if needed). The associated glypotodont material I found quite a few years back did have osteoderms that looked somewhat similar, but they usually have attachment points where other osteoderms connected and they're not shaped quite the same.

[digit]

Great to hear from someone who's seem a fair amount of both. The edges are what was hanging me (and Dr. Hulbert). The tortoise osteoderms would have had space between them and would not show signs of interfacing with adjacent osteoderms as they would with glyptodonts.

 

Thanks for chiming in.

 

Cheers.

 

-Ken

 

P.S.: Now I really want a glypto caudal osteoderm.

[Brett Breakin' Rocks]

Great Finds Ken !! 

  

    I was just in Summerville last week sloshing around in the creeks and there is nothing quite like what the Peace River looks to be. One day I'll make it out to the Peace but it looks as if I'll need some neoprene and a lack of nerve endings ..... I have the neoprene, I'm still working on the tolerance to the cold. Thanks for the trip report, looks like a wonderful spot.

 

Cheers,

Brett

[digit]

Come on down in March-May and the air temps are back up enough that it seems comfortable standing around in a cool river.

 

 

Cheers.

 

-Ken

[old bones]

Wonderful finds and a great report, Ken. Thanks for taking us along.  

[Bone Daddy]

Great report and thanks for sharing.

 

I must be a freak of nature because the cold water really doesn't bother me - which is a possibility since I am also immune to poison ivy. To be fair, I try to stay dry above the waist and do not completely submerge myself like my crazy partner Josh. (BTW, how do I tag another member in posts?)

 

Reading this makes me want to get out there again soon.....very soon.

 

 

[jcbshark]

Nice finds Ken, I'm glad you and Tammy could get out: ) good luck

out there this season! 

[digit]

More thoughts and musings on the first mystery item from above. Looking through my accumulated collection of Peace River fossils over the last couple of days I spotted a second find that matches this mystery object. Here are images of the two of them.

 

   

 

I'm now pretty certain that these are both leg osteoderms from the giant tortoise that once ambled around Florida in a very Galapagean manner. The tortoise osteoderms that I'm use to finding (not the most common of finds, but I've got a dozen or so) come in a variety of shapes and sizes but are for the most part much smaller (and sometimes much more elongate and pointy). Here is a selection of a few from my collection. The constricted ring around the base has always been, for me, one of the dead giveaways to classifying these finds as tortoise leg osteoderms.

 

   

 

If you look through enough online sources (or even some fossil ID books) you will come across the term "tortoise foot pad". Those usually have images along the lines of the big chocolate cookie looking osteoderms like my mystery osteoderm and its companion. @Harry Pristis did a good job several years ago trying to explain away the myth of foot pads but sadly information is hard to purge from the inter-webber-net and this term still pops up in searches.

 

http://www.thefossilforum.com/index.php?/topic/11901-peace-river/&do=findComment&comment=136298

 

Given that the edges of my two specimens don't show the spongy cancellous bone around the edges as would be found in glyptodont tail osteoderms but rather the constricted ring that I see on my other unmistakably tortoise leg osteoderms, I'm going to consider the case closed on this mystery. It is an amusing coincidence that John @Sacha had read this post before we went out fossil hunting in the Peace River last Thursday and one of the finds that turned up in his sifting screen was, in fact, a true Glyptotherium caudal osteoderm. The edge where it interfaced with similar osteoderms was well apparent in his specimen. I asked John to send me a photo of his find after the trip and he responded six-fold by showing me a gallery of various caudal osteoderms from his collection. The latest is the dark black one on the lower left, fresh from the river. You can plainly see from these images how different the edges are from my (tortoise) osteoderms and the different "orange peel" texture on the top. I've now got something new for my Peace River bucket list (and a lot of catching up to do, apparently).

 

   

 

While sorting though my finds (not well organized like some people's collections) I came across another odd little piece that I've been saving, hoping it was something. The more I look at this hamburger patty the more I'm convinced that this is probably just a worn down bone fragment eroded into a somewhat circular shape. One side has an outer surface that seems partially worn away exposing the spongy cancellous bone structure below. The odd but asymmetrical pointy bit extending off one edge has always intrigued me and fueled my hopes that this would one day be recognizable but I think it may just be something like a worn down piece of giant tortoise carapace (shell).

 

       

 

I hope this post may prove useful in the future to those who find osteoderms in the Peace River. Had I known they were to be this significant a part of this trip report I'd have added "osteoderm" to the topic's tags. At least anyone doing a search on TFF for that keyword will likely stumble upon this post sooner or later and will hopefully glean something useful from it.

 

 

Cheers.

 

-Ken

 

 

[Plantguy]

10 hours ago, digit said:

More thoughts and musings on the first mystery item from above. Looking through my accumulated collection of Peace River fossils over the last couple of days I spotted a second find that matches this mystery object. Here are images of the two of them.

 

   

 

I'm now pretty certain that these are both leg osteoderms from the giant tortoise that once ambled around Florida in a very Galapagean manner. The tortoise osteoderms that I'm use to finding (not the most common of finds, but I've got a dozen or so) come in a variety of shapes and sizes but are for the most part much smaller (and sometimes much more elongate and pointy). Here is a selection of a few from my collection. The constricted ring around the base has always been, for me, one of the dead giveaways to classifying these finds as tortoise leg osteoderms.

 

   

 

If you look through enough online sources (or even some fossil ID books) you will come across the term "tortoise foot pad". Those usually have images along the lines of the big chocolate cookie looking osteoderms like my mystery osteoderm and its companion. @Harry Pristis did a good job several years ago trying to explain away the myth of foot pads but sadly information is hard to purge from the inter-webber-net and this term still pops up in searches.

 

http://www.thefossilforum.com/index.php?/topic/11901-peace-river/&do=findComment&comment=136298

 

Given that the edges of my two specimens don't show the spongy cancellous bone around the edges as would be found in glyptodont tail osteoderms but rather the constricted ring that I see on my other unmistakably tortoise leg osteoderms, I'm going to consider the case closed on this mystery. It is an amusing coincidence that John @Sacha had read this post before we went out fossil hunting in the Peace River last Thursday and one of the finds that turned up in his sifting screen was, in fact, a true Glyptotherium caudal osteoderm. The edge where it interfaced with similar osteoderms was well apparent in his specimen. I asked John to send me a photo of his find after the trip and he responded six-fold by showing me a gallery of various caudal osteoderms from his collection. The latest is the dark black one on the lower left, fresh from the river. You can plainly see from these images how different the edges are from my (tortoise) osteoderms and the different "orange peel" texture on the top. I've now got something new for my Peace River bucket list (and a lot of catching up to do, apparently).

 

   

 

While sorting though my finds (not well organized like some people's collections) I came across another odd little piece that I've been saving, hoping it was something. The more I look at this hamburger patty the more I'm convinced that this is probably just a worn down bone fragment eroded into a somewhat circular shape. One side has an outer surface that seems partially worn away exposing the spongy cancellous bone structure below. The odd but asymmetrical pointy bit extending off one edge has always intrigued me and fueled my hopes that this would one day be recognizable but I think it may just be something like a worn down piece of giant tortoise carapace (shell).

 

       

 

I hope this post may prove useful in the future to those who find osteoderms in the Peace River. Had I known they were to be this significant a part of this trip report I'd have added "osteoderm" to the topic's tags. At least anyone doing a search on TFF for that keyword will likely stumble upon this post sooner or later and will hopefully glean something useful from it.

 

 

Cheers.

 

-Ken

 

 

Ken, I'm back to wondering as I have a few osteoderms that are worn enough that their base isnt clean/sharp looking. Maybe this is a question for Harry but I was wondering about some of the osteoderms that have a distinct polygonal nature to them--usually 4-6 sided on their base and/or flattened planed like sides. Does a turtle/tortoise ever produce those shapes/types? Regards, Chris 

[digit]

From my limited sample size, tortoise osteoderms (I don't believe that the aquatic turtles have any need for these) don't seem to have have the shape you are describing. Some google searching on appropriate keywords turned up some nice image galleries and, as usual, the best ones always seem to turn up on TFF. @Lori LuvsFossils posted a nice gallery of her lovely finds from the Peace River. In particular, I'd direct your attention to this one which has a nice diversity of osteoderm types:

 

http://www.thefossilforum.com/index.php?/gallery/image/25713-more-scutes-and-tortoise-spurs/

 

The polygonal osteoderms under the gator osteoderm in the upper left corner are from Holmesina. The pitted "orange peel" texture and the beveled edges are quite distinctive. They come on a wide variety of geometric polygonal shapes with 4-6 sides, sometimes with a small raised keep running down the middle. I think this matches your description above. Those on the right of Lori's image with the "rosette" pattern composed of a smaller circular raised section in the center surrounded by a tessellated ring of other small raised sections is the mark of Glyptotherium (and also the smaller Dasypus). The pointed objects in the middle of that photo between the Holmesina and Glyptotherium are tortoise leg osteoderms most of which clearly show the constriction mark around the wider base where the osteoderm attaches to the skin. The best way to picture how these tortoise leg osteoderms (please don't call them "foot pads" or Harry will blow a gasket as he's been on a crusade for years to wipe this erroneous terminology from use) look and function is to do a google image search for the African Spur Tortoise, Geochelone sulcata. What better example for leg "spur" osteoderms could there be?

 

Another image in Lori's gallery (previous to the one above) shows a nice variety of Holmesina across the top with varying numbers of sides and some Glyptotherium rosettes below that. I believe the two smaller rosettes at the bottom left corner are from the smaller armadillo, Dasypus bellus, (the "Beautiful Armadillo", don't ask me--that's the translation of the species name). It was just a little larger than the Nine-banded Armadillo we still have running around Florida today (though sometimes not quick enough to avoid becoming roadkill).

 

http://www.thefossilforum.com/index.php?/gallery/image/25712-glyptodont-armadillo-scutes/

 

I'm far from being an expert on Florida fossils or osteoderms, but I enjoy learning about both topics from the fossils I encounter. The above represents about the limit of my knowledge on osteoderms. The Xenarthra ("ground sloths") apparently had loose osteoderms embedded in their hides but from images I've seen online they are not vert distinctive and look just like smooth rounded bones. I don't know that I'd be able to recognize one if I had one in hand and, if they are not exceedingly rare, I'm sure I've tossed a few back into the river after pondering them for a split second.

 

I always enjoy seeing an osteoderm from Holmesina or Glyptotherium (or more rarely Dasypus) show up in my sifting screen. Hope this helps to spread around a little knowledge about these.

 

 

Cheers.

 

-Ken

[Plantguy]

Hey Ken, thanks for the response...

 

It was nice seeing Lori's finds again--I remember them and have both the tortoise and glyptodont types... I also spent some additional time looking at some of Harry's giant tortoise leg photos.

 

Here are three with flattened sloping sides (the pictures really dont show it well) that were making me wonder which kind I found a couple years ago. I do have some of the more traditional smooth hershey kiss cone shapes with the grooved/flared bases but I'm guessing these 3 are too badly worn to say one way or the other...I seem to find alot of the worn out stuff and my overactive imagination gets the best of me! LOL.

 

Enjoyed seeing your finds in this thread and your latest trip. Nice to see a discussion of these crazy osteoderm things here again! 

 

Regards, Chris  

 

 

[digit]

The circled one on the bottom right looks more like the tortoise one next to it but with a lot more wear obliterating the normal constriction around the base. I'd still think tortoise but you are right that it is in that gray zone (from the little I've seen from glypto ostoderms). The two circled ones on the top row look more like glypto but all the normal textural clues seem real obscure on these specimens. At least there is more to contemplate with these fossils than there is with a dugong rib fragment. Given the coloration of your specimens, I'm assuming all of these are quarry finds.

 

 

Cheers.

 

-Ken

[Harry Pristis]

Without substantial wear on the specimen, it should be easy enough to distinguish between tortoise and glyptodont.  I don't recall if I've ever posted this comparison view.  Which osteoderm is the glyptodont?

Recognize the same osteoderm in the second image?

P

[Plantguy]

4 hours ago, Harry Pristis said:

Without substantial wear on the specimen, it should be easy enough to distinguish between tortoise and glyptodont.  I don't recall if I've ever posted this comparison view.  Which osteoderm is the glyptodont?

Recognize the same osteoderm in the second image?

 

 

Thanks Harry. Thanks Ken. My apologies for my fuzzy photos that I can now see are not as they should be...my editor did some strange things again...the lt pink/green tones and lack of sharpness after I've viewed/posted it is the hallmark of the bug...dang it! 

 

I can see the differences in the comparisons...I'll have to go look at some others I have. If I find anything worth showing I'll post again. Thanks guys! Regards, Chris 

[digit]

8 hours ago, Harry Pristis said:

Without substantial wear on the specimen, it should be easy enough to distinguish between tortoise and glyptodont.  I don't recall if I've ever posted this comparison view.  Which osteoderm is the glyptodont?

Recognize the same osteoderm in the second image?

 

Agreed that it seems simple to pick the guilty party out of that rogue's gallery in the first image.

 

Are you saying that the glytodont osteoderm from the line-up in the first image is the same one pictured in the second image? I'm assuming the second image is showing paired images from the same specimen of tortoise and same specimen of glyptodont osteoderms. The glypto osteoderm appears colored different (brown) in the view showing the spongy base and (blacker) in the view from the top. The "orange peel" texture on the top surface is also not as apparent in this image.

 

Thanks again Harry for providing the info and imagery to allow me to share my learning moment with the rest of the forum.

 

Hoping to head back to the Peace next weekend (if weather and water levels hold). I'll be keeping my eyes peeled and my fingers crossed hoping that I'll finally be able to add a glyptodont caudal osteoderm to my little collection.

 

 

Cheers.

 

-Ken

[Harry Pristis]

Yes, Ken, it is the same glyptothere osteoderm in both images.  Any color or clarity differences are artifacts of lighting and the steadiness of my hand.  I made the first image in December 2007 and the second in September 2012, but it's the same marginal osteoderm (marginal because of the taper of the anchoring bone).

Here's another image that I made a few minutes ago that includes the same glyptothere osteoderm.

[digit]

Thanks. We need a special button for "Very Informative".

 

My knowledge grows slowly--but incrementally. Just learned some new information from Dr. Hulbert on the finds from my second outing to the Peace. Need to go make some updates there.

 

 

Cheers.

 

-Ken

[abach292]

nice finds! what a thread as well. looking forward to next month, I hope the water levels hold out.

[Bone Daddy]

Agreed with what the previous poster said.

 

Thanks for posting these Harry. I had found a couple of these in the past and I mistook them for tortoise. Now I know what they are.

 

 

[digit]

I'm truly glad that my little education on osteoderm matters has been on this public forum so that others may learn as well.

 

 

Cheers.

 

-Ken

[Bone Daddy]

47 minutes ago, digit said:

I'm truly glad that my little education on osteoderm matters has been on this public forum so that others may learn as well.

 

 

Cheers.

 

-Ken

And you too Ken. Thanks for posting this. Now I know what these are. I just assumed they were tortoise. Now I need to go take a closer look at a couple similar pieces in my boxes.