Mesozoic Market | Fossil Collector & Amateur Paleontology

Magnified view of a fossilized dinosaur tooth of a Saurornitholestes or Bambiraptor showing hook-shaped serrations or denticles.

A magnified view of the serrations. The hook-shaped denticles on the distal carinae is a distinct characteristic that distinguishes these saurornitholestines from the contemporary dromaeosaurid, Dromaeosaurus albertensis, as well as young tyrannosaurs individuals of Gorgosaurus or Daspletosaurus.

Fossilized dinosaur tooth of a Saurornitholestes or Bambiraptor inside of a gem jar.

A dinosaur tooth of an indeterminate saurornitholestine dromaeosaurid, possibly Saurornitholestes langstoni or Bambiraptor feinbergi from the Judith River Formation in Fergus County, Montana, USA. #FossilFriday

#dinosaur #fossil #paleontology #saurornitholestes #bambiraptor #dromaeosaurid #theropod

Fossilized mosasaur tooth of a Thalassotitan or Prognathodon showing the tip worn down.

A mosasaur tooth of an indeterminate prognathodontin, possibly cf. Thalassotitan sp. from the Peedee Formation in Holden Beach, North Carolina, USA. This robust tooth morph is comparable to Thalassotitan atrox from Morocco. #FossilFriday

#mosasaur #fossil #paleontology #thalassotitan #prognathodon

Magnified view of a fossilized crocodylomorph tooth of a Doratodon on original matrix or rock showing serrations or denticles on the cutting edge or carinae.

Magnified view of a fossilized crocodylomorph tooth of a Doratodon on original matrix or rock showing serrations or denticles on the cutting edge or carinae.

A magnified view of the crown showing the worn, but present serrations on the carinae. While we don't have any today, land crocs seem to show up independently, and quite frequently, throughout crocodylomorph evolution.

Fossilized crocodylomorph tooth of a Doratodon on original matrix or rock.

A fossilized crocodylomorph tooth of an Doratodon carcharidens from the Csehbánya Formation in Veszprém County, Hungary. This Cretaceous aged terrestrial ziphosuchian croc had serrated teeth similar to those of theropod dinosaurs. #FossilFriday

#crocodylomorph #fossil #paleontology #doratodon

In hindsight, this could have gone very poorly. So uh, always have a friend to help carry heavy objects. If sci-fi multiverse, alternate timeline stuff or whatever is real, then I'm sure there are instances where I did get fatally crushed by the Eubrontes after tumbling down stairs.

A minor correction, apparently this slab of rock is around 78 pounds according to the UPS label. That's what I thought as first, but assumed it was lighter once I managed to carry it up the stairs, but I guess I can carry close to 80 pounds. I only weigh a bit over 100 pounds, so that's surprising.

Dinosaur footprint or track of an Eubrontes, Gigandipus, or Dilophosaurus on original matrix or rock showing added staining to show clarity and a human hand for comparison.

This 11-12 inch Eubrontes weights about 50-60 pounds which made it quite dangerous to carry up stairs. Eubrontes and other similar morphologies have sometimes been attributed to basal sauropodomorphs as well, but they are generally assumed to be Dilophosaurus-sized theropods in affinity.

Dinosaur footprint or track of an Eubrontes, Gigandipus, or Dilophosaurus on original matrix or rock showing added staining to show clarity.

A dinosaur footprint of the ichnotaxon Eubrontes giganteus from the East Berlin Formation in Connecticut, USA. This Jurassic aged ichnogenus is possibly from Dilophosaurus or a similar species. #FossilFriday

#dinosaur #fossil #ichnology #paleontology #eubrontes #gigandipus #dilophosaurus #theropod

Magnified view of a fossilized crocodylomorph tooth of a Iharkutosuchus showing feeding wear on the crown.

A magnified view of the crown, albeit very worn, showing the molar-like morphology of the tooth. This is one of the weirdest archosaur teeth around as most herbivorous species tend to develop leaf-shaped teeth than the mammalian style dentition seen in Iharkutosuchus.

Fossilized crocodylomorph tooth of a Iharkutosuchus inside of a gem jar showing feeding wear on the crown.

A fossilized crocodylomorph tooth of an Iharkutosuchus makadii from the Csehbánya Formation in Veszprém County, Hungary. Unlike the leaf-shaped teeth of herbivorous crocs like Simosuchus, this genus evolved mammal-like dentition. #FossilFriday

#crocodylomorph #fossil #paleontology #iharkutosuchus

I'm not sure what this means for unserrated tyrannosaur premaxillary teeth from older deposits like the Judith River or Two Medicine Formation. Do they represent an undescribed Nanotyrannidae indet., or at least, a more basal eutyrannosaur/pantyrannosaur of some kind?

www.nature.com/articles/s41...

Close up view of a fossilized dinosaur tooth of a Nanotyrannus or Aublysodon showing the lack of serrations on the cutting edge.

While unserrated premaxillary teeth were supposedly an ontogenetically variable character, proposed to be found in young Gorgosaurus, recent studies on Nanotyrannus by Zanno and Napoli 2025 have shown this may not be the case. Which may mean they belong to Nanotyrannus lancensis and N. lethaeus.

Fossilized dinosaur tooth of a Nanotyrannus or Aublysodon showing all of the root in tact and lacking serrations on the cutting edge.

A rooted dinosaur tooth of a Nanotyrannus sp. from the Hell Creek Formation in Carter County, Montana, USA. This unserrated basal morphology was previously known as the tooth taxon, Aublysodon amplus. #FossilFriday

#dinosaur #fossil #paleontology #aublysodon #nanotyrannus #tyrannosaurid #theropod

Fossilized pair of dinosaur teeth of Nanotyrannus and a juvenile Tyrannosaurus.

Cross-section view of a fossilized dinosaur tooth of a Nanotyrannus and a Tyrannosaurus showing a hourglass and oval shaped cross-section respectively.

Comparison with what I believe is a true juvenile young Tyrannosaurus rex (right). While tyrannosaur teeth are very similar to one another, Nanotyrannus teeth are distinguished from T. rex by the hourglass (or figure eight) shape of the cross-section opposed to being oval or round in tyrannosaurins.

Fossilized dinosaur tooth of a Nanotyrannus inside of a gem jar.

A dinosaur tooth of a Nanotyrannus sp. from the Hell Creek Formation in Carter County, Montana, USA. This nanotyrannid eutyrannosaur has two species, N. lancensis and N. lethaeus. Welcome back Nanotyrannus. For good this time.

#dinosaur #fossil #paleontology #nanotyrannus #tyrannosaurid #theropod

Close up view of a fossilized leaf-shaped dinosaur tooth of a Hungarosaurus or Struthiosaurus showing ridges running down the crown and large serrations.

A magnified view of the serrations, as well as defined ridges down the crown. Hungarosaurus's close relative, Struthiosaurus, could potentially be found here as well which will likely make distinguishing isolated teeth difficult, if not impossible. They are both struthiosaurin nodosaurids after all.

Fossilized leaf-shaped dinosaur tooth of a Hungarosaurus inside of a gem jar showing some feeding wear.

A dinosaur tooth of an ankylosaur, either Hungarosaurus tormai or cf. Struthiosaurus sp. from the Csehbánya Formation in Veszprém County, Hungary. Hungarosaurus is known for its long forelimbs. #FossilFriday

#dinosaur #fossil #paleontology #hungarosaurus #struthiosaurus #ankylosaur #ornithischian

Magnified view of a partial fossilized dinosaur metatarsal of a Dzharacursor showing what may be bite marks from a predator.

A magnified view of the bone showing what may or may not be bite marks from a predator. Some of the theropods that may have hunted Dzharacursor include the tyrannosaur, Timurlengia, the carnosaur (or carcharodontosaurian) Ulughbegsaurus, and the large dromaeosaurid, Itemirus.

Partial fossilized dinosaur metatarsal of a Dzharacursor.

A partial fossilized metatarsal of a theropod, possibly Dzharacursor bissektensis from the Bissekty Formation in Dzharakuduk, Kyzylkum Desert, Uzbekistan. This species was previously referred to Archaeornithomimus. #FossilFriday

#dinosaur #fossil #paleontology #dzharacursor #ornithomimid #theropod

Fossilized softshelled turtle osteoderm or scute of a Khunnuchelys.

A fossilized osteoderm from a Cretaceous aged softshelled turtle, possibly Khunnuchelys kizylkumensis from the Bissekty Formation in Dzharakuduk, Kyzylkum Desert, Uzbekistan. Other species of this genus also occur in China and Kazakhstan. #FossilFriday

#turtle #fossil #paleontology #khunnuchelys

Pair of fossilized dinosaur teeth of a Tyrannosaurus and Albertosaurus showing both showing the tip missing.

Today is the 120th anniversary of the description of #Tyrannosaurus rex and #Albertosaurus sarcophagus in 1905 by Henry Fairfield Osborn, the two species that would define the clade, Tyrannosauridae. A pair of dinosaur teeth, albeit very worn, belonging to these two famous species. 🧪

Magnified view of the serrations or denticles of a fossilized dinosaur tooth of an unknown theropod.

A magnified view of the distal serrations or denticles. The distal serration density is 17/5mm. The mesial carinae ends half way on this specimen, so likely two thirds the way down if complete. The mesial serration density at the tail end of the carinae is 9/2mm. CBL is 14.2mm, and a CBW of 6.6mm.

Fossilized dinosaur tooth of an unknown theropod showing the top half of the tooth crown missing.

A partial dinosaur tooth of an indeterminate theropod from the Lourinhã Formation in Peniche, Portugal. It's hard to say what it is given its incomplete nature, but it's possibly either Allosaurus europaeus or a non-Torvosaurus megalosauroid. #FossilFriday

#dinosaur #fossil #paleontology #theropod

Close up view of a fossilized dinosaur tooth of an unknown pachycephalosaurid showing serrations and a raised ridge down the center of the crown.

The prominent raised ridged down the center of the crown distinguishes pachycephalosaurids from the similarly toothed contemporary basal ornithischian, Thescelosaurus. Size wise, it could lean towards Pachycephalosaurus and Stygimoloch (Dracorex) over the two smaller pachycephalosaurid genera.

Fossilized dinosaur tooth of an unknown pachycephalosaurid with the root still preserved showing a raised ridge down the center of the crown.

A rooted dinosaur tooth of an indeterminate pachycephalosaurid from the Hell Creek Formation in Carter County, Montana, USA. Genera include, Pachycephalosaurus, Platytholus, Sphaerotholus, and the controversial Stygimoloch and Dracorex. #FossilFriday

#dinosaur #fossil #paleontology #ornithischian

Magnified view of ridges down the enamel of a fossilized crocodylomorph tooth of a Deinosuchus.

A magnified view of the enamel showing pronounced ridges commonly seen in various clades of aquatic predators. This type of enamel seems to differ from those seen in the tooth taxon Deinosuchus rugosus.

Fossilized crocodylomorph tooth of a Deinosuchus showing prominent ridges running down the tooth enamel.

A fossilized crocodilian tooth of a Deinosuchus riogragndensis from the Aguja Formation in Brewster County, Texas, USA. There were multiple species of these giant crocs during the Campanian of North America. #FossilFriday

#crocodylomorph #crocodilian #fossil #paleontology #deinosuchus

Magnified view of the serrations or denticles of a fossilized dinosaur tooth of Aquilarhinus or Kritosaurus.

A magnified view of the serrations or denticles. I'm not sure if Aquilarhinus has serrated teeth like Kritosaurus navajovius. It is possible that this tooth does still belong to some species of Kritosaurus (or Gryposaurus) just based on this characteristic.

Fossilized dinosaur tooth of an Aquilarhinus or Kritosaurus inside of a gem jar showing pronounced serrations along the cutting edge.

A dinosaur tooth of an indeterminate hadrosaur, possibly Aquilarhinus palimentus from the Aguja Formation in Brewster County, Texas, USA. Aquilarhinus was previous referred to Kritosaurus and Gryposaurus. #FossilFriday

#dinosaur #fossil #paleontology #aquilarhinus #ornithopod #ornithischian