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At the moment I happen to be picking through some micro-matrix fines from Shark Tooth Hill that @ynot graciously sent to me some time ago. All sorts of interesting micro-chondrichthyan fossils are plentiful in the really fine matrix (2 mm down to 0.5 mm). I'm also finding bits of the dactyl claws of stomatopods (mantis shrimps). There are two main types of mantis shrimps--the smashers and the slashers. The smashers have front claws ending in a hardened rounded "hammer" that they use to smash through the exoskeletons of crustaceans and mollusks (with the force of a .22 caliber bullet). The slasher types hide in burrows and wait for prey (mainly fishes) to swim overhead. They dart out of their burrows and with a very praying mantis style motion impale their prey upon these spiny dactyl claws. We also find both dactyl claw parts and the rounded ends of the smasher's "hammers" at sites in Florida and this has Roger Portell at the FLMNH interested in fossil stomatopods. I recently let him know that while I haven't yet found any "hammers" in the STH matrix, I have found smaller fragments of the slashing dactyl claws which are turning up in my matrix picking. It would be really useful to have some specimens of larger fragments of these dactyl claws from STH for our research. I'm wondering if any member out there who has picked STH micro-matrix has noticed these stomatopod dactyl claw fragments and more importantly saved them with the rest of the diverse micro-fossils from this wondrous locality? If you have some stomatopod material from STH I'd love to hear about it. You can reply here or drop me a PM. Thanks in advance. Here are some images of really nice stomatopod dactyl bits from the Montbrook site as well as the more usual smaller fragments from Cookiecutter Creek. Also, a link to a great page about stomatopods and an image of the two types of claws to help you envision how these fit into the larger picture. Cheers. -Ken https://arthropoda.wordpress.com/2010/02/09/why-stomatopods-are-awesome-i-super-strength/

Looking on the web for ID, I found Stichocorys delemontensis which is a Miocene animal, while this specimen is from the Pittsburg Bluff which is Oligocene. Shape is similar I think. Again this are from a 5 mpx camera and this is about as good as the image gets @ 800X. subject is almost centered in image.

I found a strange little critter in a chunk of Tabulate coral from the Nashville area when I was cleaning it. Most fossils from the area are 438-458 million years old. Any idea what would inhabit tabulate coral? I also included some other areas of the 20 pound chunk of silicified Tabulate corals. They vary in direction and over lay each other in various directions. I added more addition pieces to show high silicification and types in the area. The little critter is about 5mm across the dome.

This is my first "new topic" post to the FF, so I hope I'm doing this correctly. If you have a microscope or equivalent and a current or potential interest in micro-fossils, you might enjoy collecting at the following historic locality: Mississippian Salem Limestone, about 5 miles east of Salem, Indiana off Rt. 160; Spergen (Spurgeon) Hill, railroad cut (Manon RR) paralleling S. Harristown Rd, 0.75 mi north of Rt. 160; south end of Trackside Road; approximately 140 meters S of Harristown, Washington Co., Indiana; diminuitive fauna; Universal Transverse Mercator (UTM) coordinates: 16S 585024.04 4272332.25. My first introduction to micro-fossils was in a paleontology lab I took during the 70’s with the focus of study on the foraminiferid, Endothyra baileyi (now called Globoendothyra baileyi). These tiny specimens were labeled “Spergen Hill” on their container without further description. A few years later, I was able to locate the source of the specimens as the type locality for the Salem Limestone (formerly, Spergen or Spergen Hill Limestone) of Middle Mississippian or Meramecean (Valmeyerian) age. Sratigraphically, it sits above the Harrodsburg Limestone and beneath the St. Louis Limestone. The locality is a railroad cut at Spergen Hill, just south of Harristown, Washington County, Indiana. The cut is relatively narrow and much caution is advised upon the advent of trains entering the cut. The rock at this locality is a medium to coarse grained, tan to gray, crossbedded calcarenite containing mostly microfossils. Macrofossils (somewhat sparse) are present in the formation but nowhere near the quantity of the microfossils (G. baileyi has been estimated at 1,000 / in3 in some portions of the strata). Besides single-celled eukaryotes (e.g., Globoendothyra), representatives of most of the major phyla are present in diminuitive form or as tiny fragments of the macro fauna (spines, plates, columnals, etc.) I’ve visited the location at least three times in the past and besides collecting macrofossils on these visits, I have also accumulated a quantity of the rock containing the microfossils. On arriving home, I pulverize the collected rock with a sledge to a fine granular size and wash and strain the residue through a porous cloth to remove any extra fine material (rock dust) The washed residue is then dried and placed in labeled plastic bags. Then, in the dead of winter when collecting is not possible for me and the “urge” to collect is compelling, I drag out a bag, place some of the residue in a shallow container under my scope and go fossil collecting and identifying! I use a very fine-pointed forceps, which I periodically ground to a piece of rubber (to avoid static electricity buildup) to pick out fossils from the residue. I find it a bit better for collecting the micros from this locality than using a wetted fine paintbrush. This location has been estimated to contain over 100 species of invertebrates on a micro level. More information can be found at http://www.fallsoftheohio.org/SalemMicrofossils.html. The attached photos were taken for a program I was giving on Indiana fossils to illustrate single-celled eukaryotes (Protozoa). The first photo shows a random selection of micro-specimens of various phyla collected from the residue with an emphasis on the G. baileyi. The second and third show sorted G. baileyi specimens and G. baileyi specimens with matrix, respectively. Two free texts with plates are available on some of the Spergen Hill microfauna at the following websites: Whitfield, R.P. On the fauna of the Lower Carboniferous limestones of Spergen Hill, Ind., with a revision of the descriptions of its fossils hitherto published, and illustrations of the species from the original type series. Bulletin of the AMNH; v. 1, article 5. (free download) https://books.google.com/books?id=ebYPAAAAIAAJ&pg=PA241&lpg=PA241&dq=whitfield,+R.P.+On+the+fauna+of+the+limestones+of+Spergen+Hill&source=bl&ots=iFhHvpc7qf&sig=XNpUBo45hKPRICv5fLdb0AlJktA&hl=en&sa=X&ei=pO8_Ve70G-vlsATq-4EQ&ved=0CCQQ6AEwAg Cumings, E.R. et al. Fauna of the Salem Limestone of Indiana. (free download). https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB4QFjAA&url=https%3A%2F%2Fscholarworks.iu.edu%2Fdspace%2Fhandle%2F2022%2F12889&ei=G_o_Va3_CveasQSCu4HADA&usg=AFQjCNGsTNbr2RKBBebd6bnuISOcqvMsPw

Still fossil hunting indoors during the summer (and the pandemic) amusing myself (and helping the FLMNH) by picking through micro-matrix from the Montbrook dig site in Florida. I've made some other posts featuring the interesting micros I've been finding to try to share a bit of the world of micro-fossils with a wider audience (Florida has more than megalodon teeth). I was picking through a sample of Montbrook micro-matrix. It was collected back in 2018 and was subsequently washed, dried, and sat in a zip-top bag for years awaiting someone to spend about a dozen hours picking through it for interesting specimens. In addition to the monotony of the very abundant common fossil types (fish verts, fish teeth, gar scales, Rhizoprionodon and Dasyatis teeth) my efforts are occasionally rewarded by spotting something out of the ordinary. Sometimes the novelties are just a rarer type of previously seen fossil--a tiny ray dermal denticle the size and shape of an asterisk * or a pretty little serrated Galeorhinus (Tope Shark/Houndshark) tooth. What really makes the long hours pay off is when I encounter a good mystery. Some of the mystery finds are only mysterious to me as they are answered promptly by Richard Hulbert when I send him micro-photographs of some "unknown". I am slowly crawling up the learning curve and broadening my knowledge of the micro-fossil types being found at the Montbrook site. The real fun happens when I get something that's a stumper--a real novelty for the locality. The Montbrook micro-matrix material has a large amount of marine (and freshwater) fish material hiding in it. There are teeth from drum, barracuda, porgy, pinfish and several other marine fish families found floating loosely in the matrix. Tiny button-shaped teeth that resemble those from drums are likely the pharyngeal teeth from wrasses. One of the former mysteries that I now have locked into my set of search images is the tiny (only a few millimeters across) pharyngeal tooth plates for a small species of wrasse. Here's one I found which was full of these little button teeth. About two weeks ago I spotted an unusual little specimen in my picking plate. I could tell from the bone structure that it was "fishy" (in a good way ) but the attached tooth type was something new that I had not encountered before. I could see that this piece was a (mostly) complete lower left quarter jaw--you can see the zipper-like symphyseal suture at the midline of the lower jaw indicating that it was not fragmented and there would be no additional teeth expected in this portion of the jaw. My first thoughts about fishes I knew that had a single tooth in each quarter jaw led me to think about parrotfishes but this was quickly dismissed because I knew that parrotfish "beaks" were composed of tiny tooth plates which are continuously added from the base as the plates wear and break-off on the occlusal surface while the fish feeds by scraping algae from the surface of the substrate. BONUS FACT: Parrotfishes ingest a large amount of calcium carbonate (old coral skeleton) while feeding and the majority of tropical white sand beaches are in fact composed primarily of parrotfish poop. Richard forwarded my photographs to a student who specializes in osteichthyan (bony) fishes and I went back to picking more micro-matrix. I had a feeling that the answer would be blindingly obvious in hindsight. Had I thought about it for a moment or two more I probably could have arrived at the answer myself but so many of these mystery finds turn out to be something unexpected that I just trusted that an expert would soon solve the mystery for us. Our fishy expert was in the process of a long cross country move to continue her education at UC Berkeley but before long we got our answer--as obvious as I'd predicted. In her opinion the jaw piece belonged to a member of the order Tetraodontiformes and likely in the family Tetraodontidae (pufferfishes). The answer is right there in the scientific name (Greek, tetra = four + Greek, odous = tooth, teeth) referring to the 4 large teeth fused into a beak-like structure for feeding on hard shells of crustaceans and mollusks. A little bit of searching online quickly turned up images that closely matched my find confirming this diagnosis. A related family in the Tetraodontiformes is the Diodontidae (known as porcupinefishes, balloonfishes, blowfishes but also confusingly as pufferfishes). The mouth plates for this family are fused into two plates, upper and lower (Greek, di = two + Greek, odous = tooth, teeth) and are relatively common finds in the Florida fossil record. Anybody who has hunted the Peace River long enough has encountered at least one of these solidly constructed mouth parts with stacks of tooth plates edged in fine maxillary teeth. @Harry Pristis has a fine example of Florida finds in his library of images. There are copious additional images available online with a simple search. These diodontid tooth plates also occur occasionally in the Montbrook micro-matrix but it appears that the tetraodontid jaw specimen likely represents a new family group for the Montbrook faunal list. It is great fun when a tiny find starts as a micro-mystery, serves as a learning example to expand my knowledge base, and finishes by expanding the envelope about what is known of the taxonomic diversity of the site. Cheers. -Ken

No, not named for the famous dive/snorkel spot in Grand Cayman where tourists can interact (usually quite safely) with swarms of Southern Stingrays but instead referring to the abundance of Dasyatis sp. teeth from the Montbrook fossil site in north-central Florida. While this site is a treasure trove of fossil material providing huge numbers of specimens of turtles as well as other creatures like alligators, gomphotheres, tapirs, peccaries, llamas, and ever an early saber-toothed cat, many taxa on the faunal list are only known from micro-fossils. In addition to valuable and scarce fossil remains providing evidence for things like snakes, lizards, frogs, salamanders as well as several species of birds, the micro-matrix is loaded with huge numbers of more common fossils. A variety of tiny fish teeth and vertebrae (and lesser numbers of more delicate ribs and skull fragments) are common finds. There are a number of species of minuscule shark teeth as well--though the majority seem to be from a species of sharpnose shark (Rhizoprionodon sp.) with a few novelties tossed in to make it interesting. By far and away the most common chondrichthyan fossil at this site are from stingrays. In a report of the relative abundances of chondrichthyan specimens from this site (encompassing nearly 13,000 specimens) the vast majority (well over 9,000) are tiny Dasyatis teeth. The preservation colors at this site are quite different from the phosphatic black/gray coloration predominantly found in Florida creeks/rivers. Most are tans and light browns with a number of creamy white teeth that are so bright and clean that they look like they could have been shed yesterday. I'm presently picking through some finer material that was washed through a fine brass screen so the finds tend to be around a millimeter in size (requiring a microscope to spot on my picking plate). Last night I finished a batch and was amazed at the density and diversity of color, form, and size (some really tiny juvenile teeth in there as well). I decided to take a "wallpaper" image of a spread of these tiny teeth for fun. For reference, the field of view in this image is roughly the size of a US postage stamp. Cheers. -Ken

I've spent a little time today picking through some very fine micro-matrix from Cookiecutter Creek. This is material that was caught by my 1/20" sifting screen and is so small that I have to use my camera-microscope to see things clearly. I'm searching for some of the rarer micro-fossils that occur in this creek (and actually make Cookiecutter Shark teeth seem common. Just came across what is probably the smallest Cookiecutter Shark (Isistius triangulus) tooth I think I've ever found. It's one of the posterior teeth from the lower right side. Posterior teeth are smaller and the crown starts forming an angle to the root in comparison to the more anterior teeth which are straighter. This is not the most posterior tooth in the row (called a "commissural" tooth) as these are severely angled and have an interesting extension to one side of the root. This tiny treasure measures only about 2 mm in height and narrower in width (the scale in the photo is 0.5 mm). Just thought you'd want to see one of the smaller of the smalls. Not quite at the level of scanning electron microscopy (SEM) but getting in the neighborhood. Cheers. -Ken

Hello all, As part of my dissertation I have been sifting for micro-fossils using Braiser's (1980) white spirt method. The samples have yielded a range of micro-fossils, most of which I have been able to identify. However, this has stumped me. I believe it to be a tooth/toothplate from a fish, the enamel texture is similar to tooth textures I have seen before, though I cannot identify the species or if it is one. Any help or advice with this would be greatly appreciated! Cheers, Jacob.

This morning I finished picking through some collections of micro-matrix I made earlier this year for a project I was working on. I was lucky enough to be able to meet-up with Jack, @Shellseeker to visit a collecting spot on Little Payne Creek where I was able to collect a nice bucket of micro-matrix. The fossils in this feeder creek to the Peace River often exhibit much nicer coloration than the grayscale fossils found in the Peace River itself. I came across a tiny shark tooth (8.5 mm x 5.5 mm) that has me stumped as I've not seen anything quite like it before while micro-matrix picking. You'll see it has lovely caramel cream coloration (looks tasty enough to eat ) but the thing that I found unusual about this tooth is the presence of tiny side cusps. The only species I encounter here in South Florida that has side cusps is the Sand Tiger Shark (Carcharias taurus) but the tooth shape is entirely wrong for this species. The shape is generally consistent with Mako (Isurus) but not with the cusps. The age of the material from this location--Peace River Formation (Miocene-Pleistocene) would seem to exclude something like a baby Carcharocles auriculatus or C. angustidens and though I've heard of megs showing primitive cusps on baby teeth, the shape does not fit my concept of Carcharocles. I'm stumped, which is good because this means there is a learning opportunity for me here. Anybody have any thoughts on this tiny caramel beauty? Cheers. -Ken