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Just a few bits that I received yesterday, some of which may be of interest to fans of Moroccan fossils. Firstly, a box full of the ubiquitous hybodontid shark fin spines (or 'spin fines', as I often call them during my less lucid moments). Common Kem Kem finds, but I do like them. The coin for scale in the middle is a shiny British fivepence, which is 18mm across, or 0.72/inch. Most of them need some prep, especially this beast, which may test my prep abilities, given how encrusted it is and how delicate these are. Secondly though, are these Crinoid float bulbs. I've never knowingly seen these before. Apparently, according to dealers online, they are from the Erfoud region. I can't find a great deal of information about how they actually functioned, but I'll have a little search of the scientific literature when I get the chance. The idea seems to be that they either floated on the top of the sea, allowing the crinoid to travel great distances, or they were temporarily anchored to the sea floor. Either way, they are magnificent things. Surface texture of the above specimen. Specimen #2 Specimen #3. As they are hollow, they have beautiful crystal growths on the inside, which can be seen when they break.
Hello! I found this chunk of something in Frankstown, MS while looking for shark teeth. There is so much petrified driftwood there and many pieces look similar to this. I picked this out at first thinking it was wood.. but I didn't see the little bumps along one side (I'm being very generic because I don't want to call it something it isn't and I'm not sure yet what it is ) until I got home. I also noticed when I got home that it is hollow and looks a bit like bone. After seeing this, I thought it was probably a fin spine or a ray barb. Others say it is a barb, but if it is, I'd love to know more. I would think it would have denticles along both sides, but the other side is rounded. Rays found at this location are Brachyrhizodus wichitaensis and Brachyrhizodus mcnultii. Specimen is 2" long
Hello everyone, I'm a student in Milan and I'm currently struggling in trying to identify this fossil shark fin spine. Which taxon do you think it belongs to ? This speciment had been found in Northern Italy. The exact stratigraphic position is yet to be determined, but I can say for sure it's either Upper Rhaetian or Lower Hettangian. The spine is almost 11 inches long (28 cm, 29,2 cm if you count the missing tip) and is yet incomplete, for it lacks the basal structure and there's a big gap at 1/3 of its lenght (see images below). It also shows a pattern of denticles near the tip ( they stop abruptly 10,5 cm from the tip). The internal morphology feature an enlarged cap layer, a thin enameloid layer (lacking in some spots) near the tip while wider near the base and a thin trunk layer. The lumen, the internal cavity, is rain drop shaped and is filled with matrix for more than half of the spine lenght.