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Marshosaurus bicentesimus is a midsize theropod in the Morrison Formation in the Megalosauridae family. Over the past few years, teeth are becoming available in the open market simply because dealers/diggers are now more aware of this species and like to sell them. Isolated teeth from the Morrison Formation are very difficult to diagnose because of their similarity and all require an understanding of additional characteristics than normal, in hopes of properly identifying them. The best I can do is to look at other reference publications some which include similar teeth from Portugal and Germany which describe morph types and then assign them to the best taxon. I also have been able to obtain information from C. Hendrickx recent publication Taxonomic identification of isolated theropod teeth 2019 that took measurements of these teeth and this edit reflects that information. . The following information is needed to identify these teeth: 1)Photo of tooth, both sides and base and one of the mesial edge (outer) 2)Serration density of both edges 5 mm wide at midline 3)Dimensions: CBL, CBW, CH 4) Locality: State and County Three Key Characteristics :. 1) Mesial Carina should extend down at least 2/3 First and most important since this is a Megalosaurid the anterior carina (serrations) only come up to 2/3 of the way down the keel. 2) Serrations on both edges should be different (Hendrickx Study 8 teeth) The serrations are finer than most other large theropods in the Morrison. Mesial edge must be finer than Distal DSDI : Denticle size density index = Mesial Density ÷ Distal Density Should be Greater than 1.15 Mesial at Centerline MC : around 20/ 5 mm Distal at Centerline DC : 15-17/ 5mm, posterior teeth may be higher 3) Crown Base and Height ratios These teeth are compressed and the ratio looks at that compression. Marshosaurus teeth must fall into these parameters CBR: Crown Base Width (CBW) ÷ Crown Base Length (CBL) = Dentary (around 0.5-0.6), Maxillary (around 0.3) CHR: Crown Height Ratio (CH) ÷ Crown Base Length (CBL) = 1.5 to 2.5 may be lower on distal teeth 4) Other Characteristics Might show light transverse undulations Might show some short Interdental sulci but typically absent Representation of teeth that are similar to Marshosaurus C1-3 Reconstruction Skull of Marshosaurus from Utah Museum of Natural History. So you can see variation of the teeth in jaw Reference: 1) Hendrickx, C., Mateus, O., and Araújo, R. 2015. The dentition of megalosaurid theropods. Acta Palaeontologica Polonica 60 (3): 627–642. 2) Journal of Iberian Geology June 2017, Volume 43, Issue 2 , pp 257-291 Analysis of diversity, stratigraphic and geographical distribution of isolated theropod teeth from the Upper Jurassic of the Lusitanian Basin, Portugal 3) Multivariate and Cladistic Analyses of Isolated Teeth Reveal Sympatry of Theropod Dinosaurs in the Late Jurassic of Northern Germany Oliver Gerke, Oliver Wings Published: July 6, 2016 https://doi.org/10.1371/journal.pone.0158334 4) A second new Theropod dinosaur from the late Jurassic of east central Utah 1979 by J Madsen

A new article from Geology of the Intermountain West: A preliminary report of the fossil mammals from a new microvertebrate locality in the Upper Jurassic Morrison Formation, Grand County, Utah Article https://www.utahgeology.org/openjournal/index.php/GIW/article/view/25 PDF https://www.utahgeology.org/openjournal/index.php/GIW/article/view/25/47

Boy this one has me stumped and I haven't got a clue what it is. From the late Jurassic of the Morrison Formation. I cleaned out the base and its a concave cavity. Any help pointing me in the right direction would be appreciated. Thanks 1 cm tall.

These camarasaurus metacarpals were discovered within a 20' area of the digsite. A number of other camarasaurus bones were found in the same area. They all came from a smaller, sub-adult camarasaurus. I'm trying to figure out if they all come from the same foot. (left, front foot) I have only two, or three worn out toe bones, and the big claw was missing. High energy water ripped this dinosaur apart. Parts of a diplodocus were scattered around the same area.

A interesting new found. Late Jurassic fossil plant from Liaoning, China.