Search the Community

Below is an unidentified phytosaur tooth from the Norian of the Chinle Formation which I've been struggling to identify to a genus or species level. Thanks in advance for any proposed ID's Othniel

I recently purchased an odd little archosaur jaw from the Wealden at Bexhill-on-Sea in East Sussex, UK. It's 14.88mm in length and 4.03mm tall, with a single remaining tooth of approximately 1mm in height. The seller told me he thought it would be Aigialosaurus, something I thought odd due to that genus only being known from Hvar in Croatia, and being much younger (Cenomanian) than this specimen (Valanginian). However, it turns out that a jaw was found at this locality at some point that has since been moved to the Bexhill Museum and was identified as Aigialosaurus (though, based on what, I don't know): While I'm working on figuring out whether the jaw in the other thread can indeed by attributed to an early mosasauroid (Aigialosaurus?), I wanted to ask people in this thread what they make of my particular section of jaw. Ventral Terminus (end of jaw) 1 Terminus (end of jaw) 2 Observe the tooth attachment with raised sockets, not unlike in mosasauroids. Details of tooth attachment. Here are the photograph of the jaw from Bexhill that was identified as Aigialosaurus again, for ease of reference (source): So, what do you guys think? Reptile or fish? Crocodile, lizard? Do you think my jaw compares well to the one identified as British Aigialosaurus? @caterpillar @Praefectus @ThePhysicist

Hi everyone, this is my first post on here. This specimen was labelled as a 'dinosaur jaw bone' and it was found in the Hell Creek Formation near Glendive, Montana. It is about 27 mm long. It does seem to me it belongs to a reptile of some sort but I haven't been able to find anything on the internet to identify it with any more specificity so I'd really appreciate your expertise in identifying it. Thanks everyone!

About a year and a half ago, I purchased a couple items with this set of fossils being one of them. They are real fossils and based on the other things that he was selling, I believe the location was labeled correctly but not the ID of what their owner was. It was labeled "the dromaeosaurid, Deltadromeus"...you can sort of see where I'm coming from when I decided to question the ID. Based on some research it does seem to be the upper and lower leg of an archosaur of some sort though it doesn't look like a crocodylomorph. Any idea of what I can label it as, even if it's something like "Theropod indet.". the two smaller pieces are from the same bone the at one point were held together by some glue of some sort. My guess is some sort of non-Ceratosaurine theropod based on how straight the larger (what seems to be the upper leg bone) is. I don't think that it's from a spinosaurid because the proportions seem off (assuming these bones are from the same individual) so that sort of leaves a Carcharodontosaurid when looking at everything together though I'm wondering what you guys think it could be.

Here's a tooth I bought at the gem show back in the days when Moroccan vertebrate stuff was starting to appear at Tucson and other shows. I've been meaning to show it to people for years. It's from the Kem Kem Beds (Cenomanian), Taouz area, Morocco. It's about 61mm long with cutting edges that appear to be slightly crenulated rather than finely-serrated. It's oval in cross-section on the root end but the crown becomes blade-like toward the tip so it is somewhat labiolingually compressed. I assume it's a crocodile tooth but thought it might have a small chance at being from a dinosaur. I'll hit up the "Kem Kem regulars" for comment but am interested what others say as well. @Troodon @Haravex @LordTrilobite Thanks, Jess

Hello everyone, first post in this forum! If I make any newbie mistakes please let me know and I’ll edit this post/remember for next time. I have a broken reptile tooth sifted from Big Brook (a stream near Marlboro, NJ) that dates to somewhere between the Late Campanian and Early Maastrichtian. I posted this online at another point and it was identified as a crocodile tooth from the original pictures I posted. I’ve been sitting on this one for a while though and it doesn’t seem to line up with the teeth from other known crocodilians and from this area (Brachychampsa, Borealosuchus, Hyposaurus, etc). Can anyone offer a second opinion? It has really prominent anterior ridge on the front of the tooth which makes me think it’s possible a theropod but it doesn’t look like Dryptosaurus. The back half is broken which means I don’t have any serrations to use as an ID. I’ve included the files in this post. I have also included some bonuses to these image though. I believe I found what appears to be a bird femur in the brook but I’m not certain if this is a quaternary find or actually from the same formation as this tooth. Anyone have a family id or insight on how to check if this is fossilized or just turned black from the soil? I also included some images of saurornitholestine teeth which I personally thought are close in appearance to this tooth. Thinking I might be too hopeful on that ID but thought it was worth sharing my thoughts lol. Material of these dinosaurs has been found in New Jersey!

Loc: https://www.geopark-thueringen.de/entdecken-erleben/nationale-geotope/standard-titel Age: Triassic, Keuper For wchich Archosaur, this tooth belongs? I know that it's hard to say, but maybe somebody can do this

Hello dear members, Today I'd like to talk about my latest fieldtrip, to the Late Triassic tracksite of Zone, Lombardy prealps, Italy. However, I'd like to make it clear that it involved no fossil collecting, because of the scientific interest of the site and of italian laws, that prevent (almost) any form of this activity. I know there is the "Fossil sites" section, but I thought that here my post would have reached more people. I apologize in case this is not allowed. Let's not waste any more time! Italy is quite well know for its tracksites, in particular those bearing dinosaur tracks: Altamura (the largest tracksite in Europe!) and Lavini di Marco, just to give an example. On the other hand sites of Late Triassic age, bearing archosaurian footprints are poorly documented. Zone is a tiny village located nearby the Lake Iseo, in the Southern prealps, some 80 km (50 mi) east of Milan (see the red arrow on the map below). Back in the Late Triassic (Carnian) this area was an alluvial fan, characterized by a semiarid climate and, further to the south, by the occurrence of a series of volcanic edifices. Tracks are, in fact, preserved in terrigenous-volcaniclastic beds. Ripple marks and groove casts can be found too. The material is represented by a total of about 70 footprints, arranged in six trackways on two different layers. The older displays three trackways that cross each other, the younger three distinct trackways. Footprints are only moderately preserved, nonetheless several anatomical details are evident on those of the younger level. In addition to traditional mapping methods, a laser scanner was employed to obtain high-quality 3D digital models. Let's talk about who left this footprints for us to admire! Those of the younger level are referred to a quadrupedal trackmaker with plantigrade, pentadactyl pes (distal portion of the hind limb) and manus (distal portion of the fore limb). They have been assigned to the ichnogenus Brachychirotherium, known by a global distribution and probably left by a crurotarsan archosaur. It is not clear whether it was a rauisuchian (predator) or an aetosaur (armored vegetarian). On the field, I must admit that I was a little disappointed. Judging by the pictures published in the 2009 paper that described the outcrop, at least two trackways were quite distinct and visible. However, that was not the case: only 4 tracks (two manus and two pes) were indeed immediately identifiable. I guess that's possibly due to two factors: on the one hand weathering (the fine grained sandstone is very fragile), on the other hand inclination of solar rays. Tracks are best visible in raking light, but I visited at around 10-11 am in a clear February day. In the summer period I'm quite sure that much more could be seen!! In order to highlight the footprints and compare with the presente state, I chose to show also a pictures taken from the paper: you can distinghuish it easily, because it is in b/w. Today this is the best that you could ask for in this section (older layer) The overall best preserved manus-pes track, in the younger layer. Reconstruction of this set of footrprints Close up of the Manus, scale bar is 5 cm (2 in). total lenght of the track: some 30 cm (11,8 in). The second best preserved manus-pes association Reconstruction of a rauisuchian (on the left) and an aetosaur (on the right). On top lower right digital model of the best preserved trackway (I showed you the picture of the first two sets of imprints). A rauisuchian The significance of the Zone tracksite is that it represents the first definite ichnological record of archosaur tracks found in Lombardy and footprints are among the best preserved, although an upcoming paper is going to feature recently found tracks that are even better preserved (and I gave my contribution in the excavation campaign!). On the field, I must admit that I was a little disappointed. Judging by the pictures published in the 2009 paper that described the outcrop, at least two trackways were quite distinct and visible. However, that was not the case: only 4 tracks (two manus and two pes) were indeed immediately identifiable. I guess that's possibly due to two factors: on the one hand weathering (the fine grained sandstone is very fragile), on the other hand inclination of solar rays. Tracks are best visible in raking light, but I visited at around 10-11 am in a clear February day. In the summer period I'm quite sure that much more could be seen!! Anyway, it was a great experience: easy access, few people walking by, great scientific value! I hope that you liked my short report, Fabio

Found these in East Central Arizona. A deep wash has cut through a rock ledge containing lots of the footprints. Still working on trying to get some of the bigger rock slabs hauled out.

Hi! I recently aqcuired quite a lot of "microfossils" to kick off my Triassic collection, as I personally find it one of the most interesting time periods and while I am aware possibly not all of them are ID'd correctly I just wanted to get some nice fossils from this time period regardless of their ID's. All the fossils I acquired are from the Bull Canyon Formation, Dockum Group, San Miguel County, New Mexico, USA (Norian age) But I myself am not very knowledgeable yet in this material as I just started my collection but I am aware that some if not most of the ID's on these fossils given by the seller might be wrong as everything I read about the Bull Canyon formation says that the formation isn't that well discribed yet. I tried to make the photo's as good as I could, but it wasn't always easy given their extremely small size, so I hope the quality is good enough to work with. So I am kinda hoping is someone here on the forum would like to give it a try to see if he/she could confirm or disprove given ID's. Thank you in advance! The first set of 2 teeth were listed as the Phytosaur "Pseudopalatus" teeth which after doing a bit of research is considered a junior synonym for "Machaeroprosopus" The next collection of 3 teeth were listed as the Pseudosuchian "Revueltosaurus" The next tooth was listed as a "Theropod indet" tooth, and I know there are at least 2 species of theropod present at Bull Canyon, a Coelophysid called Gojirasaurus and a herrerasaurid called Chindesaurus. But I am not even sure whether this tooth is dinosaurian or not. The next set of teeth were listed as "Arganodus" lungfish teeth And the final tooth was listed as a "Sphenodont" (Rhynchocephalia indet.) tooth with affinities to Clevosaurus (which is found in Nova Scotia, Great Britain and China)

https://www.eurekalert.org/pub_releases/2019-01/fm-idc012319.php http://blogs.discovermagazine.com/deadthings/2019/01/31/antarctanax/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A DiscoverBlogs (Discover Blogs)

Hello all, I just picked up this pretty vert and am not quite sure about the ID. The seller advertised it as Coelophysis, but it doesn't seem to be a match. It's from Bull Canyon formation, Quay County, New Mexico (Upper Triassic). It measures 2 1/2". The seller provided good pictures, so I've attached some of those. I can provide more and even take some of my own if needed! Thanks, and hopefully we can figure out an ID on this one!

Early- and Mid-Cretaceous Archosaur Localities of North-Central Texas. Guidebook for the field trip held October 13, 2015 in conjunction with the 75th Annual Meeting of the Society of Vertebrate Paleontology in Dallas, Texas https://www.researchgate.net/publication/283711331_Early-_and_Mid-Cretaceous_Archosaur_Localities_of_North_Central_Texas https://figshare.com/articles/Early_and_Mid_Cretaceous_Archosaur_Localities_of_North_Central_Texas/1608173 http://chrisnoto.com/publications.html Yours, Paul H.

Rauisuchians are some of my favorite prehistoric beasts, rather specific but I'm wondering if anyone on here on the forum has any material to show I'd love to see. So far I've been only able to obtain postosuchus teeth and recently begrudgingly missed out on some Batrachotomus kupferzellensis.

First of all, hello to all of you on the Fossil forum- My name is Erik. newbie here, first post. Secondly, I'm exceptionally curious as to what organism in the fossil record has the first confirmed gastrolith (non-exolith) presence. I found and read through Fruitbat's research, and he had some very interesting articles about gastroliths, some of which I've seen, some of which I have not. I feel that Gastroliths are incredibly important to Archosaur evolution because they fulfill much the same role that differentiated teeth for thorough mastication do in mammals. Of course, proving that a differentiated tooth came from a synapsid is much, much easier than proving a gastrolith found outside of any skeletal remains (an exolith) came from an Archosaur. I'm sure many of you know most of this already... any information you can provide would be appreciated.

Here is another peice of my work, this profile is on the Stegosaurus and once again I would like to see what you all think but keep in mind I kind of wrote this in a biased way, as in I used the theories I think are true without mentioning other ones so Forgive me for that. But hey, At least it's pretty simplified. Stegosaurus is one of the Most well known of all dinosaurs along with the T.rex and the Velociraptor. Despite this very, very, very, few people know what it actually looked and behaved like. For example the Stegosaurus has Sexual Dimorphism which means a difference in the males and female's. Females have sharp pointed Plates along its back while the males back plates would be rounded kind of like a squashed circle. Stegosaurus is part of the Stegosauri family that arrived on the scene in the early Jurassic and died out at the end of the Jurassic Period. Stegosaurus grew to be 30 feet long and 9 feet tall which 3 foot long plates and 3 foot long thagomizers which were the spikes at the end of the tail, that it used for self defense. Stegosaurus has extremely small heads even for a Stegosaurs, They fed on Fern cycads and Conifers which were the dominant plant species in the Jurassic period in North America. Another thing, Stegosaurus is native to North America in places such as Wyoming and South Dakota along with animals like Brachiosaurus and the Brontosaurus Stegosaurus also have a thick armor on its neck represented by thick rock like scales. While the bone plates and thagomizers in the skeleton are large, they were much larger in life as they were covered in keratin and thick sponge bone like material. It's notable to mention that Stegosaurus tail spikes called thagomizers are at the tip of the tail and unlike many archosaur tails which get thicker and stiffer near the end instead are very flexible like the tail of a monkey in order to swing around their thagomizers with great accuracy against predators, killing a Allosaur in one blow or at least wounding it badly. Fossil Records of Allosaurus show puncture woulds in areas like the leg or against the pubic bone which is part of Pelvis. These were caused by the Stegosaurus which was defending itself or a baby, Now while they have these large spikes to protect themselves they also have these large kite shaped sponge plates which were not protection but was used for Courtship for females and to confuse predators, This means it would flush blood into its plates and they would turn to bright red along with other colors, the body would likely be green or brown while the plates would have bright colors much like a Baboons Colorful face. Stegosaurus was discovered by the Famous Charles Marsh in 1877 and Stegosaurus had this very wide gap of space in between its hips and Marsh thought in this space it had a Secondary brain. Now he thought this because this elephant size animal had the brain the size of a dogs brain. He thought this was not enough and he had to had a secondary brain to help it function. Not true it did not have a second brain and no dinosaur or reptile ever had a second brain.

I found this tooth while searching my collection of Sussex Wealden, Hastings bone bed. Similar to the small size ornithopod dinosaur Hypsilophodon premaxilla teeth, but this species can be ruled out. It is more similar to the small ornithopod Echinodon, Purbeck beds, Dorset premaxilla teeth. The crown is smooth and asymmetrical. The root curls up at the end, similar to some Iguanodon teeth in original early illustrations of the Iguanodon species. I prepped the tooth out completely from the matrix. Tooth is very small being 5mm long. Can anyone help me with identification of this tooth?