Sacha Posted April 13, 2020 Share Posted April 13, 2020 Went to Zolfo Springs, Pioneer Park to put in for a trip on a very pleasant 92 degree Easter Sunday. Lots of people out, but most were doing the social distancing thing......many were not. As usual I was alone for most of my time on the river and it did turn out to be a rather productive day. Horse, camel/llama, gar, gator, Giant Tortoise, turtle, tons of shark teeth and the most interesting finds, 2 unusual osteoderms (top center in the picture). Using the 1/4" screen again to save my right arm muscles, slows down the process, but the tiny stuff makes the day feel more productive than shoveling constantly into the 1/2" screen. Especially in Zolfo where most of the gravel is less than 1/2" in size. Here's the take for the 5 hours, most of which will wind up in the donation/give away section. 6 Link to comment Share on other sites More sharing options...
digit Posted April 13, 2020 Share Posted April 13, 2020 Very nice! Glad you got out out the house and into the river. Had thought about trying to get out but since we rent canoes at Canoe Outpost we'd have to be close to others (particularly on the bus ride to the put-in). Now that they've closed access to Brownville Park, our usual full-day run is unavailable anyway. At least I've still got some micro-matrix and my camera-microscope to keep me busy. It takes me 7-8 hours to pick through a single kilogram of the really fine stuff under the scope so I could keep myself busy (and entertained) for months. Can we see a close-up of the two osteoderms you mentioned? Cheers. -Ken Link to comment Share on other sites More sharing options...
Sacha Posted April 13, 2020 Author Share Posted April 13, 2020 19 minutes ago, digit said: Can we see a close-up of the two osteoderms you mentioned? -Ken How's this? The little one may be a wierd giant armadillo edge piece, but it's pretty thin. 1 Link to comment Share on other sites More sharing options...
digit Posted April 13, 2020 Share Posted April 13, 2020 I was definitely thinking edge piece for the little one. The only other item I know that has that general shape would be tortoise osteoderm ("leg spur") and it doesn't seem to have the constriction that those tend to have at the base. The larger one looks definitely (always dangerous to use the word 'definitely' when running at the edge of your experience/knowledge ) like a glypto rosette or possibly the center of a poorly mineralized rosette. Those tend to have the very obvious vascular pores on the smooth inner surface and your piece is punctured dead center. Always nice to find something in the sifting screen that is not immediately identifiable and makes for a good head-scratcher. Cheers. -Ken Link to comment Share on other sites More sharing options...
old bones Posted April 13, 2020 Share Posted April 13, 2020 Nice, John! I'm with Ken... grateful for the micro matrix since I can't get out. Link to comment Share on other sites More sharing options...
Shellseeker Posted April 13, 2020 Share Posted April 13, 2020 2 hours ago, Sacha said: Went to Zolfo Springs, Pioneer Park to put in for a trip on a very pleasant 92 degree Easter Sunday. Lots of people out, but most were doing the social distancing thing......many were not. As usual I was alone for most of my time on the river and it did turn out to be a rather productive day. Horse, camel/llama, gar, gator, Giant Tortoise, turtle, tons of shark teeth and the most interesting finds, 2 unusual osteoderms (top center in the picture). Using the 1/4" screen again to save my right arm muscles, slows down the process, but the tiny stuff makes the day feel more productive than shoveling constantly into the 1/2" screen. Especially in Zolfo where most of the gravel is less than 1/2" in size. Here's the take for the 5 hours, most of which will wind up in the donation/give away section. Ditto, ditto, ditto John. Glad you got out. I shared the day 3 bridges upstream. It was just gorgeous. I love the river. It keeps me sane, and makes me a better person when I am not there. My find of the day is that piece of fossilized cypress. Do not get much wood year by year. 4 The White Queen ".... in her youth she could believe "six impossible things before breakfast" Link to comment Share on other sites More sharing options...
Andy B Posted April 13, 2020 Share Posted April 13, 2020 Nice finds. My three years at this and I don't have as many shark teeth as you have on that towel. Link to comment Share on other sites More sharing options...
Shellseeker Posted April 13, 2020 Share Posted April 13, 2020 3 hours ago, Sacha said: How's this? The little one may be a wierd giant armadillo edge piece, but it's pretty thin. I have had entire Glypto scutes that are 1/4 inch wide or 1.5 inches wide. I have wondered if it was a disease as the scutes were forming. I realize that I do not know how the individual rosettes expand in size as the animal grows in size. After all they were not born at the size of a 1966 volkswagon beetle. The White Queen ".... in her youth she could believe "six impossible things before breakfast" Link to comment Share on other sites More sharing options...
Sacha Posted April 13, 2020 Author Share Posted April 13, 2020 31 minutes ago, Andy B said: Nice finds. My three years at this and I don't have as many shark teeth as you have on that towel. Andy, we are certainly blessed with an abundance of shark teeth, so much so that we really don't pay much attention to them. @Shellseeker seems to be the Peace River guy that studies them the most on an individual basis and Jack probably collects 15 pounds or so a year (and that's a conservative estimate). Fortunately kids love them, teachers love them and museums love them for activities the hold for the public. And for us they make the screen loads interesting while we're waiting for mammal stuff to show up. 2 Link to comment Share on other sites More sharing options...
Sacha Posted April 13, 2020 Author Share Posted April 13, 2020 24 minutes ago, Shellseeker said: I have had entire Glypto scutes that are 1/4 inch wide or 1.5 inches wide. I have wondered if it was a disease as the scutes were forming. I realize that I do not know how the individual rosettes expand in size as the animal grows in size. After all they were not born at the size of a 1966 volkswagon beetle. The one that Ken thinks is for a Gliptodont bothers me because it is inly 1/4 to 3/8" thick and has the hole for the hair in the middle. I checked all my Glypdodont osteoderms and all are thicker and don't have the hair hole. Link to comment Share on other sites More sharing options...
digit Posted April 13, 2020 Share Posted April 13, 2020 Thicker is to be expected as most of mine are pretty chunky as well. Here are some photos I could find quickly on the internet which show these holes: You may have the time to read through an old scientific paper on glyptodonts between visits to the river. Glyptodonts of North America Gillette, David D.; Ray, Clayton E., 1981 https://doi.org/10.5479/si.00810266.40.1 Here's some interesting passages from that paper (emphasis mine): CARAPACE The dermal armor ("coat of mail" of other authors) is the single most outstanding characteristic of glyptodonts. The armor largely consists of coalesced, tightly sutured individual scutes. The scutes covering the trunk region of the body are polygonal, usually six- or four-sided, and they are so united as to inhibit trunk mobility. The structure so formed is the carapace, analogous to the turtle carapace and more closely resembling it than the mobile carapace of the related armadillos. In Glyptothenum there are approximately 1600 scutes in the carapace, each firmly united with the next except toward the margins of the carapace, where the quadrilateral shapes of the scutes allowed limited mobility. The carapace covers the entire trunk region except for the ventral surface of the body, providing nearly impenetrable protection from predators. In adults the scutes are thick, lateral ones measuring up to 60 mm or more in thickness, interior scutes 30 mm or more, and, compared with armadillo scutes, they are relatively porous and light. The disposition of the component scutes of the carapace into rows was established early in the ontogenetic development of the individual. Maximum transverse dimensions of the component scutes were achieved upon attainment of full scute-to-scute contact, with subsequent growth possibly limited to increasing the thickness of each scute. Holmes and Simpson (1931) adequately treated the microstructure of the carapacial scutes of North American representatives. For the purposes of this study, no additional information has been gathered, and their discussion appears to be entirely accurate. Carapacial scutes exhibit a relatively uniform construction, variable only in quantitative and geometric details. The undersurface of a scute is typically weakly concave, with several large vascular foramina penetrating to the interior. Except for ankylosed attachment in the pelvic region, the scutes generally occupied a dermal position, so that the undersurfaces are generally smooth, or, in some instances, weakly striated as an apparent indication of attachment by connective tissue. and: Surface texture of the scutes is punctate, owing to numerous vascular channels that lay beneath the scales for communication with the dermis and epidermis. These pass into the interior of the scute and communicate with the cancellous central layer. Also penetrating the external surface of the scutes are variable numbers of larger hair follicles issuing from within the circular grooves at the boundary of the central figure. Typically, one follicle is set at the intersection of a radial groove, with the circular groove on the anterior side of the scute. Dorsal and anterior scutes possess as many as five large follicles; the frequency diminishes laterally and rearward so that away from the dorsal region follicles are less numerous or absent. That these large pits lodged hairs, rather than blood vessels, was argued convincingly by Holmes and Simpson (1931). The hole dead center on your thin piece does seem out of place as the hair holes should be at the intersections of the lines of the rosette pattern on the top (as can be seen on the images above). I can't think what else this could be from the texture and hexagonal shape though the thickness and piercing seem out of character for the norm. Perhaps @Harry Pristis has seen some that look like your odd specimen? Cheers. -Ken 5 Link to comment Share on other sites More sharing options...
Gizmo Posted April 13, 2020 Share Posted April 13, 2020 Very nice, congrats! Link to comment Share on other sites More sharing options...
Mark Kmiecik Posted April 13, 2020 Share Posted April 13, 2020 Thank you both for sharing photos of your finds. Mark. Fossil hunting is easy -- they don't run away when you shoot at them! Link to comment Share on other sites More sharing options...
Andy B Posted April 13, 2020 Share Posted April 13, 2020 6 hours ago, Sacha said: The one that Ken thinks is for a Gliptodont bothers me because it is inly 1/4 to 3/8" thick and has the hole for the hair in the middle. I checked all my Glypdodont osteoderms and all are thicker and don't have the hair hole. Some day I am going to come to Florida! Link to comment Share on other sites More sharing options...
digit Posted April 16, 2020 Share Posted April 16, 2020 Did a quick look through my collection of Glyptotherium osteoderms and located this one which is of normal thickness and has one prominent hair hole on the outer surface right at the intersection of the inner ring and one of the radial grooves. You'll notice on the under surface that there is a large pore dead center as in your thin osteoderm. Cheers. -Ken Link to comment Share on other sites More sharing options...
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