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Howdy all, Does anyone know what this appalachiosaurus skull reconstruction is based on? I've seen it and another that looks more like a Dryptosaurus and I'm not sure which is the correct one based on the holotype.

Found in Nevada. Washoe county. It is heavy, (have yet to weigh it). Length around 250 millimeters/ 25 centimeters.

Just saw this on a Facebook a preprint just released from a very prestigious dinosaur paleontologist Nicholas Longrich. From the abstract "Here, we review multiple lines of evidence and show that the totality of evidence strongly supports recognition of Nanotyrannus as a distinct species." "placement of Nanotyrannus outside of Tyrannosauridae as a non-tyrannosaurid member of Tyrannosauroidea." https://osf.io/preprints/paleorxiv/nc6tk/?fbclid=IwAR3_YkPSpKBQXk5Aiff0sJRKsl59dIqqO5DXveSjV-tx24Vs6ZLuRZdcaHs

Howdy all. I've discussed the relationships between Nanotyrannus and Appalachiosaurus to albertosaurines and to eachother before, and today I'm wondering if relationships could be determined by the shape of their teeth. Comparing the teeth of nanotyrannus and appalachiosaurus, they are very similar to eachother, almost identical. They are also relatively similar to the teeth of gorgosaurus, though not as much. I believe it's already been established that these animals are relatively closely related, but I think this to be extra evidence to the case. (These fossils are not mine)

So, after watching a video that Peter Larson posted on Instagram about nanotyrannus, I was pretty convinced that it is a valid genus. That got me wondering. Where does it fit in the tyrannosaur family tree? Is it more related to Tyrannosaurus rex, or another tyrannosaur? I saw an article that was trying to prove that Nanotyrannus was, instead of being in tyrannosauridae with animals like tyrannosaurus and tarbosaurus, it was in dryptosauridae with dryptosaurus and appalachiosaurus. I'm very curious about everyone else's opinions but I myself am rather convinced. links: Pete's post: https://www.instagram.com/tv/CjoNNdojfjp/?igshid=YmMyMTA2M2Y= Nanotyrannus article: http://psdinosaurs.blogspot.com/2021/08/evidence-of-subadult-nanotyrannus.html?m=1

I recently read that the only skeleton currently known of Appalachiosaurus was of a juvenile, and the adult animal was significantly bigger. The juvenile skeleton was about 21 feet long, and the animal likely weighed 1,300 pounds. This skeleton is about the size of a juvenile Tyrannosaurus rex (using the "Jane" specimen for scale, BMRP 2002.4.1) and, this raises a question in my mind. Is it possible that Appalachiosaurus montgomeriensis would have attained adult sizes close to what we see in adult specimens of Tyrannosaurus rex? And as such, could we classify it as a megatheropod? Of course there are several other factors in this, such as age, growth stages, and environmental pressure that the animal may have experienced in life.

Greetings! This is my first share on this forum. I was looking through my collections, and one thing popped my mind was this tooth -- a tooth of Xiongguanlong baomoensis，which i found in 2014 but I could not give a very conclusive identification until earlier this year. I was lucky enough to travel along with a group of scientists into the Gobi desert in Northern China. That day we was traveling in the border zone of three different provinces, basically middle of nowhere. This basin is where most dinosaur from Gansu found -- including X. baomoensis, Auroraceratop rugosus, Lanzhousaurus magnidens, etc. I found two dozen of borken teeth on a random hill. In the beginning I thought those teeth could be either iguanadon, hadrosaurus or some crocodilians. After collecting them and bringing them back to Beijing, I went focusing on other real-life project (preparing for college, preparing for grad-school, etc.). It became a memory sealed in attic and lost until I was re-examining the crocodilian fossils I found from the same trip. Then my eyes fell on this tooth, which I recalled seeing similar teeth from the Lanzhou Geological Mesuem and labelled X. baimoensis. After a further comparing with other teeth from the same clade in museums in China, I am certain that this tooth could belongs to X. baomoensis. X. baomoensis is one of the most mysterious member of the superfamily Tyrannosauroidea, and only thing I could be sure that they could grow larger than the specimen preserved in Lanzhou -- for I found a large theropodian matatarsal from the same site and it's certainly larger than the skeleton they demonstrates. I put it somewhere in my mountains of boxes, please allows me some time to look for it.

What is the most likely attributable identity for the Tyrannosauroid remains at Phoebus Landing of the Tar Heel Formation? What I am referring to specifically are bones documented in Baird and Horner's 1979 paper which speaks of a distal third of a right femur that is attributed to cf. Dryptosaurus and is smaller than the holotype of D. aquilunguis. It is also compared with Albertosaurus which shows similarities as well but that's expected with Eutyrannosaurs. Also there is another distal left femur of a tyrannosauroid shown to be found in a Hypsibema bonebed and originally attributed to the Hadrosaur taxon as a tibia but later revealed to be part of the femur of Tyrannosauroide Keep in mind at the time they were attributed to tyrannosauridae until dryptosaurus was shown to be part of an outgroup from the main family. My only question is, are these specimens possibly referrable to Appalachiosaurus instead of Dryptosaurus? It could be possible as the time of description of these specimens Appachiosaurus was not described yet. There are a few flags that could make such bones the cf. Appalachiosaurus instead, like the more pronounced medial condyle than that of Dryptosaurus which is smaller and less noticeable. This I noticed with specimen ANSP 15330. Although it is overrall smaller than the Dryptosaurus holotype this could be just a sign of it being in a juvenile ontogenetic stage. And despite being smaller not only is it's medial condyle larger, the politeal pit and the intercondylar fossa are deeper and more prominent. Although I cannot say the same for the larger left femur Cope mistakenly thought was a Hypibema tibia. This femur is larger than the Dryptosaurus holotype however it's fossa and processes aren't as pronounced. Although this could be attributed to the fact it is largely abraded and weathered. Here is the subadult Appalachiosaurus right femur from the holotype (ignore the left tibia included below it);

A new Tyrannosauroid is described in this paper, unfortunately its paywalled. I show it not just because its new but once thought to be aTarbosaurus sp, see photos below. So until its studied, reviewed and published identifications are just preliminary. So let me welcome Jinbeisaurus wangi the first theropod dinosaur so far found in Shanxi Province, Huiquanpu Formation Scale: 1 meter https://www.sciencedirect.com/science/article/pii/S0195667119301909 Some poor screenshots of images Much better Q photos thanks to Jim Kirkland

A mid-Cretaceous tyrannosauroid and the origin of North American end-Cretaceous dinosaur assemblages New species named Suskityrannus hazelae [...]The North American fossil record of dinosaurs from approximately 90 million years ago (Late Cretaceous) is one of the most poorly sampled and least understood times of the Cretaceous Period. The new dinosaur, named Suskityrannus hazelae, is from a dinosaur assemblage that documents this critical interval. Suskityrannus is one of the last smaller tyrannosauroids, which at 9 feet long would have likely weighed less than 100 pounds and stood only about 3 feet at the hip. It is also one of the most complete skeletons of any non-tyrannosaurid from North America – all of the older fossil occurrences consist of teeth, isolated bones, or a partially associated skeleton.[...] News: CLICK Scientific Paper [paywall]: CLICK Always nice to see new discoveries regarding tyrannosaurids