Bill Heim
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Click on the little icon that looks like a mountain and select the file from your computer. Then add a comment to describe or discuss the specimen.
Definitely looks like wood. Looks just like a chunk of wood that has been sitting outside in the elements for a while. Also there are no pores in the areas where the insides have been exposed as you would expect with bone.
Fossilized pearls have been found. They are rare just like modern pearls, but do occur. They develop just like modern pearls with an irritant like sand inside the shell. From your images, it does appear to be just that. Because they are fossilized, they are not as attractive as modern pearls.
The author is the person who published the species name first. The key word here is published. The name is usually followed by the publishing date however for some reason myFOSSIL didn’t want to follow that convention. If the genus name was later changed but the species name was not, the author will be in parans. So here is an example of an author: (Agassiz, 1843). The author was Agassiz who published the species in 1843, but later the genus name was changed. In myFOSSIL that would be either Agassiz or (Agassiz).
A modern bone will usually be white or sometimes stained and be fairly light as it is porous. A fossil will be mineralized and often stone-like with increased density due to mineralization. Here is a fossil billfish rostrum. Note less porous appearance, the colorization and more stony texture.
An associated set is where a shark died and dropped all its teeth. It is usually a once in a lifetime find, so I wouldn’t count on finding one.
hastalis lower teeth have more angular roots than planus lower teeth which are more rounded. I will get some scans when I get a chance. As far as hastalis goes, the teeth, particularly the roots are very comparable to Carcharodon carcharias. So you can place them in jaw position by matching them up with a GW jaw. Separating lateral and posterior teeth from I. oxyrinchus can be problematic, but in the end, how much does it matter. As far as STH goes, almost all the oxyrinchus I have seen from there have been pretty small, so I would grade them by size.
Here is an image (modern Mustelus jaw) produced by a handheld microscope. I had to adjust the image with a image processor as it was too light and washed out. Note the pinkish tint which also can be adjusted but with more difficulty. I find the scanner produces superior images; however the microscope has its use as it can get into tight and awkward places that the scanner cannot.
http://www.elasmo.com/frameMe.html?file=paleo/sth/shrkhill_new.html&menu=bin/menu_fauna-alt.html
and http://www.elasmo.com/frameMe.html?file=paleo/sth/shrkhill_new.html&menu=bin/menu_fauna-alt.html
Note: Cosmopolitodus is now Carcharodon. The images are clickable which brings up a page on the genus (including ones not found in STH). I don’t believe there are any Negaprion found in STH.
As for your image: A5 is Isurus oxyrinchus, the remainder of the A row I would have to examine in person; B3, B4, B5 are Carcharhinus; C row is Carcharodon hastalis; D2, D3 are lower C. hastalis; D4 is lower C. planus; E4, E5 are C. hastalis, the remainder I would have to see; F1, F3, F4, F5 are C. hastalis, F2 is lower C. planus.
I recommend looking at the extant (modern) dentitions as a guide to separating genera: http://www.elasmo.com/frameMe.html?file=paleo/sth/shrkhill_new.html&menu=bin/menu_fauna-alt.html
Bill H.
Jack’s answer on microscopes was excellent.
For photography, believe or not, I use a flat bed scanner. You need one that has some 3d capability (the one on my printer can only scan paper thin items as with all paper feed scanners). Currently I am using an older Epson V300 but a V600 would probably work. By adjusting the dpi setting you can magnify to an incredible amount. The attached image is a 6mm cookie cutter tooth (Isistius) at 1200 dpi and a 6-gill (Hexanchus) tooth scanned at 600 dpi. At 9600 dpi you could paper your wall with it. You have to do some post processing such as cleaning up dust, removing background reflections and adjusting brightness and contrast but you have to do that with a camera as well. The problem with a camera is that setup takes forever and then you have to readjust almost after each picture and play with the lighting, the lens and the settings. A scanner takes far less time and I believe produces superior images. Larger items can be scanned as well. Attached is a scan of an almost 7 inch megalodon and a quarter of a nurse shark (Ginglymostoma) jaw. Here is a link to a how-to guide: http://www.elasmo.com/frameMe.html?file=refs/terms/scanning.html&menu=bin/menu_refs-alt.html
I would lean towards Carcharhinus isodon lower tooth as well (lower teeth are not serrated in this species). A very rare find.
It is a partial fish jaw, probably Trichiurus sp. Hairtail fish. See: http://www.elasmo.com/frameMe.html?file=leecreek/lc_fish/lc_fishSpp.html&menu=bin/menu_leecreek-alt.html click on The teleosts on the top of the page. More specifically: http://www.elasmo.com/leecreek/lc_fish/fishSp.html?tgtSp=tric_sp
Palaeohypotodus is a genus found in the Palaeocene to the Early Eocene. Teeth from Aurora are primarily middle Miocene with the occasional early Pliocene tooth mixed in. What you have is a posterior Odontaspis reticulata. You were probably put off by the rugose basal enamel striations on the labial side where the enamel meets the root. In my modern Carcharias jaws and my modern Odontaspis jaw, the posterior teeth have heavy basal rugose enamel striations even as the lateral and anterior teeth do not.
Left/Rights mixed up
10 associated teeth from Gardenier Phosphate (Ft. Meade, FL) Late 1980’s
Left to right, 5 Upper teeth: All measurements taken on the labial side.
Upper left lateral tooth possibly L3. Overall slant height 56mm, width across the root 49mm, overall height 50mm, width across enamel 48mm, enamel height (from lowest point of enamel) 35mm, enamel height from center of enamel 29mm.
Upper right anterior tooth probably A2. Overall slant height 70mm, width across the root 54mm, overall height 64mm, width across enamel 50mm, enamel height (from lowest point of enamel sides) 51mm, enamel height from center of enamel 45mm.
Upper right anterior tooth probably A3. Overall slant height 64mm, width across the root 49mm, overall height 59mm, width across enamel 48mm, enamel height (from lowest point of enamel sides) 44mm, enamel height from center of enamel 39mm.
Upper right lateral tooth possibly L4. Overall slant height 49mm, width across the root 43mm, overall height 40mm, width across enamel 43mm, enamel height (from lowest point of enamel sides) 33mm, enamel height from center of enamel 28mm. (note due to tip wear may 1 add mm to heights)
Upper right posterior tooth possibly P1. Overall slant height 49mm, width across the root 35mm, overall height 30mm, width across enamel 34mm, enamel height (from lowest point of enamel sides) 23mm, enamel height from center of enamel 21mm. (note due to tip wear may add 1 or 2 mm to heights)
10 associated teeth from Gardenier Phosphate (Ft. Meade, FL) Late 1980’s
Left to right, 5 Lower teeth: All measurements taken on the labial side.
Lower right Anterior tooth possibly A1. Overall slant height 57mm, width across the root 40mm, overall vertical height 51mm, width across enamel 37mm, enamel height (from lowest point of enamel) 40mm, enamel height from center of enamel 36mm.
Lower right anterior tooth probably A2. Overall slant height 56mm, width across the root 54mm, overall vertical height 51mm, width across enamel 34mm, enamel height (from lowest point of enamel sides) 38mm, enamel height from center of enamel 33mm. (note due to major tip feeding wear may add 3 or 4 mm to heights)
Lower symphyseal (or parasymphyseal) anterior tooth probably S1 (yes it appears megalodon and Otodus had lower symphyseals often known as Hubbell teeth). Overall slant height 49mm, width across the root 32mm, overall vertical height 45mm, width across enamel 48mm, enamel height (from lowest point of enamel sides) 33mm, enamel height from center of enamel 31mm.
Lower right lateral tooth possibly L1. Overall slant height 58mm, width across the root 39mm, overall vertical height 54mm, width across enamel 39mm, enamel height (from lowest point of enamel sides) 38mm, enamel height from center of enamel 32mm. (note due to tip wear may 1 add mm to heights)
Lower left lateral tooth possibly L2. Overall slant height 57mm, width across the root 40mm, overall vertical height 51mm, width across enamel 39mm, enamel height (from lowest point of enamel sides) 39mm, enamel height from center of enamel 35mm. (note due to feeding tip wear may add 2 or 3 mm to heights)
