Dakotaraptor: Beast of the Week

This week we will be revisiting an unfortunately very confusing dinosaur.  Let's check out Dakotaraptor steini.  Dakotaraptor was originally published on in 2015 and was claimed by the head author to be a very large dromaeosaur, in the same family as Deinonychus and Velociraptor.  It would have lived in what is now South Dakota, United States, during the very late Cretaceous Period, 66 million years ago.  From snout to tail it was estimated to measure about eighteen feet long, which would have made it one of the largest dromaeosaurs known. Other dinosaurs that would have been from the same environment include Tyrannosaurus, Triceratops, Pachycephalosaurus, Edmontosaurus, Anzu, and Acheroraptor.  The genus name, Dakotaraptor, translates to "Dakota Thief/Hunter" in reference to where it was found.

Life restoration of what the creature associated with Dakotaraptor MAY have looked like if it was indeed an unenlagiine. (I included it's other misidentified parts too if you know what to look for!)

Since the initial discovery and publication, many the fossils associated with Dakotaraptor have, under more close examination, turned out to be from other animals.  The original bones weren't found articulated in any sort of death position, but were more jumbled up in what likely used to be the bottom of a body of water, so it makes sense that multiple different dead animals ended up there over time and were eventually fossilized.  Some of the bones turned out to belong to the large oviraptorosaur, Anzu, as well as Tyrannosaurus, and even a prehistoric Soft-shelled turtle, called Axestemys.  

Photograph of what was originally thought to be the "killer" retractable toe claw of Dakotaraptor that has since been recognized as possibly being from a Tyrannosaurus hand.

That being said there are still a few bones that were associated with Dakotaraptor that as of now appear to be from some kind of large dromaeosaur.  More recent peer reviewed research suggests Dakotaraptor may actually belong to the unenlagiine branch of dromaeosaurs, the group known for having very long narrow snouts, based on what little material there is.  Until these bones can be formally studied further, we may never know for sure.

References

Arbour, V.M.; Zanno, L.E.; Larson, D.W.; Evans, D.C.; Sues, H. (2015). "The furculae of the dromaeosaurid dinosaur Dakotaraptor steini are trionychid turtle entoplastra". PeerJ. 3: e1957.

DePalma, Robert A.; Burnham, David A.; Martin, Larry D.; Larson, Peter L.; Bakker, Robert T. (2015). "The First Giant Raptor (Theropoda: Dromaeosauridae) from the Hell Creek Formation.".Paleontological Contributions (14).

Jasinski, Steven E.; Sullivan, Robert M.; Dodson, Peter (2020-03-26). "New Dromaeosaurid Dinosaur (Theropoda, Dromaeosauridae) from New Mexico and Biodiversity of Dromaeosaurids at the end of the Cretaceous". Scientific Reports. 10 (1): 5105.

Hartman, S.; Mortimer, M.; Wahl, W. R.; Lomax, D. R.; Lippincott, J.; Lovelace, D. M. (2019). "A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight". PeerJ. 7: e7247.

Unenlagia: Beast of the Week

 This week we will be checking out an amazing little bird-like dinosaur.  Check out Unenlagia comahuensis!

Unenlagia was a bird-like theropod that lived in what is now Argentina during the late Cretaceous period, roughly 89 million years ago.  From snout to tail Unenlagia may have measured about seven feet (2.1m) long, but estimates vary since it's known from fragmentary remains.  When alive it likely ate meat, possibly specializing in smaller prey or fish.  The genus name translates to "Half-bird" due to the dinosaur's limbs which were particularly similar to those of modern birds.  In fact when it was first discovered in 1986, it was thought by paleontologists studying it to be a kind of prehistoric bird.  More recently Unenlagia was determined to be more closely related to dinosaurs like Velociraptor, being a member of, or very closely related to the family of dinosaurs called dromaeosaurids.

Watercolor reconstruction of Unenlagia comahuensis by Christopher DiPiazza.

Sadly Unenlagia is only known from several bones, so we aren't positive about how it looked in life exactly.  The bones we do have, however, have an interesting history to them regarding how paleontologists think about dinosaurs and their relationship to birds.  The upper arm bone and shoulder blade of Unenlagia was originally thought to be adapted for flapping by paleontologists studying it.  This is what led them to believe that Unenlagia may have been either a kind of prehistoric bird extremely closely related to birds.  Some even hypothesized that Unenlagia may have been capable of flight.  More recently, however, it was determined that Unenlagia's arms were positioned more similarly to those of dromaeosaurids, like Velociraptor and Deinonychus, and did not have the range of motion of modern bird wings, thus implying it was indeed flightless.  

Photograph of Unenlagia's bones from Gianechini's 2011 paper.

Since Unenlagia's discovery, dinosaurs that are more complete than, yet extremely similar to the parts of Unenlagia we do have, give us a better idea of how it looked in life.  These dinosaurs have been given their own subfamily, called unenlagiinae, named after the earliest discovered member.  Based on more complete members of this group, we can guess that Unenlagia may have had long, slender legs and a long, narrow snout, lined with cone-shaped teeth. Because of these features some hypothesize unenlagiines may have specialized in hunting small prey and/or fish in life.  Unenlagiines also tended to have proportionally smaller arms than those of other dromaeosaurids.  

That is all for this week!  As always feel free to comment below!

References

Agnolin, F.L.; Novas, F.E. (2011). "Unenlagiid theropods: are they members of the Dromaeosauridae (Theropoda, Maniraptora)?". Anais da Academia Brasileira de Ciências. 83 (1): 117–162.

Carpenter, K. 2002. "Forelimb biomechanics of nonavian theropod dinosaurs in predation". Senckenbergiana Lethaea 82: 59–76

Gianechini, F. A.; Apesteguía, S. (2011). "Unenlagiinae revisited: Dromaeosaurid theropods from South America". Anais da Academia Brasileira de Ciências. 83 (1): 163–95.

Hartman, S.; Mortimer, M.; Wahl, W. R.; Lomax, D. R.; Lippincott, J.; Lovelace, D. M. (2019). "A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight". PeerJ. 7: e7247.

Matías J. Motta; Federico L. Agnolín; Federico Brissón Egli; Fernando E. Novas (2020). "New theropod dinosaur from the Upper Cretaceous of Patagonia sheds light on the paravian radiation in Gondwana". The Science of Nature (journal). 107 (3): Article number 24.

Norell, M.A.; Makovicky, P.J. (1999). "Important features of the dromaeosaur skeleton II: information from newly collected specimens of Velociraptor mongoliensis". American Museum Novitates (3282): 1–45.

Novas, F.E.; Puerta, P.F. (1997). "New evidence concerning avian origins from the Late Cretaceous of Patagonia". Nature. 387 (6631): 390–2.

Novas, F. E.; Pol, D.; Canale, J. I.; Porfiri, J. D.; Calvo, J. O. (2008). "A bizarre Cretaceous theropod dinosaur from Patagonia and the evolution of Gondwanan dromaeosaurids". Proceedings of the Royal Society B: Biological Sciences. 276 (1659): 1101–7.

Stegouros: Beast of the Week

This week we will be checking out a recently described, and very unique little armored dinosaur.  Say hello to Stegouros elengassen!

Watercolor life reconstruction of Stegouros elengassen by Christopher DiPiazza.

Stegouros was a plant-eating dinosaur that lived in what is now Chile during the late Cretaceous period, between about 75 and 72 million years ago.  It was a member of the ankylosaur group of dinosaurs, known for sporting bony armor all over their bodies, but it was extremely tiny for that group, only measuring about six feet from beak to tail.  The genus name, Stegouros, translates to "roofed tail" in reference to the bony structures growing from the top of its tail (more about that in a bit) and the species name, elengassen, is the name of a mythical creature known for its armor from Aonik'enk folklore, the indigenous people of the area in which Stegouros' bones were unearthed. 

Photograph of the known skull parts of Stegouros. Image from the paper by Scoto-Acuna Et al.

Stegouros is known from an almost complete skeleton.  Almost the entire rear half of the body is known, plus armor plates, and even an almost complete skull. Stegouros had a slightly curved beak which could have been used for clipping vegetation to eat.  It also had small teeth in the back of its mouth with serrations, ideal for shredding plant material before being swallowed.  It had  relatively small osteoderms on most of the upper part of its body, but the real impressive armor was on its tail.  Unlike some of its relatives, like Ankylosaurus, which are famous for having bony clubs on the tips of their tails, Stegouros had a series of wide flat pieces of bone growing from the sides of the tail and eventually fusing together to form a solid flat piece of bone at the end of the tail, forming an almost plant-like shape.  The whole structure is best described as being similar to the Aztec weapon, called a macuahuitl.  Stegouros may have used this amazing tail to defend itself from potential predators, or perhaps even to fight members of its own species for dominance or over territory, mates, or resources.

Photograph of the tail of Stegouros.

Paleontologists have determined that Stegouros evolved separately from the two other major groups of ankylosaur dinosaurs, the narrow-snouted nodosaurids, and the club-tailed ankylosaurids, forming a third major branch of armored dinosaurs, called Parankylosauria that split off earlier from the other two.

References

Soto-Acuña, Sergio; Vargas, Alexander; Kaluza, Jonatan; Leppe, Marcelo; Botelho, Joao; Palma-Liberona, José; Gutstein, Carolina; Fernández, Roy; Ortiz, Hector; Milla, Verónica; Aravena, Bárbara; Manríquez, Leslie M. E.; Alarcón-Muñoz, Jhonatan; Pino, Juan Pablo; Trevisan, Cristine; Mansilla, Héctor; Hinojosa, Luis Felipe; Muñoz-Walther, Vicente; Rubilar-Rogers, David (2021). "Bizarre tail weaponry in a transitional ankylosaur from subantarctic Chile". Nature. 600 (7888): 259–263.

Mystipterus: Beast of the Week

This week we'll be checking out a newly described prehistoric mammal that I was privileged enough to help introduced to the world.  Let's look at Mystipterus austinae!

Watercolor reconstruction of Mystipterus living in what is now north Dakota, 32 million years ago.  It would have shared its home with land snails, a legless burrowing lizard, and the early canid, Hesperocyon.

Mystipterus was a prehistoric mole that lived in what is now North Dakota during the middle Oligocene period, about 32 million years ago.  Known from mostly just a lower jaw, its body length is estimated at only a few inches long (about 7 centimeters) from nose to tail.  Like its living relatives, it was likely a meat-eater, sniffing out and devouring most invertebrates and possibly other kinds of smaller animals it came across.  The genus name translates to "Impossible to Identify" because of its dubious identity after it was first discovered. It was initially interpreted as a bat, but has since been more accurately identified as a mole.

Mystipterus one of the earliest known moles.  By comparing the fossils that have been found to those of modern kinds of moles, paleontologists have predicted that Mystipterus would not have resembled the more specialized moles, with their enlarged front limbs for digging.  Rather it was most similar to moles in the genus Uropsilus, which are more generalized.  The common name for this group is the shrew-moles, since they in many ways resemble shrews.  It may have even had a long, trunk-like nose, like some shrews have.  

Jaw and teeth from Mystipterus featured in the 2023 paper, by Korth Et al. referenced below.

Like its modern relatives, Mystipterus likely spent most of its time underground, possibly coming out at night to hunt. It may also have been a strong swimmer in life, like many modern moles and shrews are, especially since the rocks its bones were found in indicate it would have inhabited a wet environment with lots of slow-moving rivers and streams.  Since it was so small, it would have needed to avoid predators, especially while above ground, like the early canid, Hesperocyon, whos bones were found in the same area as Mystipterus'.

References

Korth, W. W.; Boyd, C. A.; Emry, R. J. (2023). "Additional small mammals from the Oligocene Brule Formation (Whitneyan) of southwestern North Dakota". Paludicola. 14 (2): 57–74.

Maryland Dinosaurs: Major Discovery!

 As you probably know, if you have been reading this blog for a while or follow me on any social media, I was born in and spent the majority of my life in New Jersey. What you may not know, however, is that I moved down to Maryland several years ago.  It was pretty sad because that means I'd be farther away from some of my favorite things, like the American Museum of Natural History, Hadrosaurus, Dryptosaurus, and good pizza.  One positive thing of the move, however, is it means I'm now living extremely close to a unique dinosaur fossil site, called the Arundel Formation, where some amazing dinosaur bones have been unearthed.

Photo of the Arundel formation I took while at the press release.  Just out of frame in both directions there are parking lots and warehouses.

The Arundel Formation used to be a mining area during the late 1800s, but now is surrounded by warehouses and office buildings.  Fossils have been discovered there for decades, including many tree and other plant fossils, like pinecones and even pollen, as well as bones from several kinds of dinosaurs, like Maryland's official state dinosaur, Astrodon.  All the fossils here are from the early Cretaceous period, about 115 million years ago, in what was a slow-moving river with surrounding swamps at the time.

Dr. Thomas Holtz speaking at the press conference about the kinds of dinosaurs that have been found at the Arundel formation.

Earlier this week a press conference was held at this site with exciting news.  Teams of paleontologists and volunteers, led by John-Paul Hodnett, just this year started uncovering many bones from not one, but several different species of dinosaurs, some of which are previously only known from teeth and other very tiny fragments, as well as at least one completely new taxa!  As stated, this site has been yielding fossils for many decades, but this many bones from this many different species at once is a first.

Below is a breakdown of the newest dinosaur discoveries shared from this press release.

Leg bone from a very large theropod

Watercolor reconstruction of Acrocanthosaurus, which may have lived in what is now Maryland.

The largest theropod bone on the eastern side of the country was discovered at the Arundel Formation just this year.  Based on the size of the tibia, the whole dinosaur is estimated to have been roughly thirty eight feet long from snout to tail.  

John-Paul Hodnett speaking about how the fossils formed at the press release from within the Arundel formation.  The big bone still in the ground at his feet is a tibia from a very large theropod.

Based on fragmentary material found at this sight in the past, as well as the time period the formation is from, this leg could belong to Acrocanthosaurus, but it could also be something entirely new depending on what further examination shows.  

Astrodon bones and a claw.  

Watercolor life reconstruction of Astrodon, Marylands state dinosaur.

Astrodon is Maryland's official state dinosaur.  It was a sauropod, related to Brachiosaurus and Camarasaurus, and was likely the largest animal in its community when it was alive.  This past year more bones from Astrodon, including a foot claw, have been discovered, giving us a more complete picture of this dinosaur's skeleton.  

Recently unearthed Astrodon fossils from the Arundel site.

It is possible these bones are from the same individual, which was a subadult when it died, that we already have an incomplete skeleton of on the fossil record, based on the size and location in the site they were found.

Priconodon bones.  

Very rough sketch of what Priconodon may have looked like.

Priconodon was a plant-eating armored dinosaur, from the nodosaur group of ankylosaurs, characterized by usually sporting long, thorny spikes running down their flanks.  For years, Priconodon was only known from teeth and very small bone fragments.  

Gigantic Prictonodon tail vertebra unearthed recently at the Arundel site.  My hand for scale.

Just this year, however, whole bones, including some truly massive vertebra, have been discovered.  Based on the size of these vertebra, Priconodon could very well have been one of the largest, if not THE largest armored dinosaur ever found!

New species of tyrannosauroid teeth

Watercolor reconstruction of a generic early Cretaceous tyrannosauroid, with three fingers on each hand, long legs, and feathers.

Teeth from what appear to be a tyrannosauroid have been discovered this year at the site for the first time at this location.  

Tyrannosauroid tooth recently unearthed from the Arundel formation.

Unlike giants like Tyrannosaurus rex, which lived at the very end of the Cretaceous, tyrannosauroids during the early cretaceous were usually relatively small, but likely fast-moving and covered in feathers.

Dromaeosaur teeth

Deinonychus, which may have lived in what is now Maryland.

Dromaeosaur fossils have been unearthed at this site, possibly belonging the famous, Deinonychus, based on size and time period.  This year more teeth that match this dinosaur were unearthed.

Ornithomimosaur bones and claw

Bones from an ornithomimosaur, group of dinosaurs that connvergently resembled ostriches, have been found at this site, including a bone unearthed just this year.  

watercolor reconstruction of a generic early cretaceous ornithomimid.  They tend to have proportionally larger heads and small teeth, compared to their toothless later relatives.

Like the dromaeosaur bones, ornithomimosaur bones have been uncovered at this site before, but having new material will add to how much we can actually learn about them and hopefully help us create a more accurate picture of them in this part of the world. 

Ornithomimid fossils recently unearthed from the Arundel formation.

Small coelurosaur theropod

A few very small bones and teeth from some kind of small bird-like theropod have been found at the Arundel site.  Unfortunately they aren't diagnostic enough to narrow it down any more than being from a coelurosaur, the broad group of theropods that includes tyrannosaurs, dromaeosaurs, and birds.  The teeth appear to be straight and pointed, however, which is unusual.  (I wonder if it was a kind of unenlagiine) Hopefully we'll learn more soon.

In addition to all these dinosaurs, the fossils of several other animals, including crocodiles, turtles, stingrays, and mussels were unearthed this year.  Furthermore, fossils from other dinosaurs and other animals have been found here in the past and may come up again as digging continues, including mammals and a small early ceratopsian, similar to the western US contemporary, Aquilops.

Watercolor reconstruction of Aquilops, which lived at the same time as the dinosaurs unearthed at the Arundel formation.

The news of so many bones being pulled out of this sight is extremely exciting.  Not only because they will vastly increase our understanding of previously very mysterious dinosaurs, but also because we have at least one totally new species. Even more exciting perhaps, is the fact that its all taking place on the east coast, an area not normally associated with major dinosaur fossil sites.  I can't wait to see what else is uncovered in the coming days!

Masiakasaurus: Beast of the Week

This week we shall be looking at an awesome little dinosaur with teeth unlike any other!  Check out Masiakasaurus knopfleri!  Masiakasaurus was a meat-eating dinosaur that lived in what is now Madagascar during the late Cretaceous period, about 70 million years ago.  From snout to tail an adult would have measured between six and seven feet (2m) long.  The genus name, Masiakasaurus, translates to "Vicious lizard/reptile" and the species name, knopfleri, is in honor of singer/songwriter/guitarist, Mark Knopfler, who's music the paleontologists who found this dinosaur's fossils were listening to during their time in the field.

Life reconstruction in watercolors of Masiakasaurus by Christopher DiPiazza.

Masiakasaurus belonged to the family of dinosaurs called noasauridae.  They are a branch of the broader group of theropods, called ceratosaurs, which also includes the larger, more well known, Ceratosaurus and Carnotaurus, to name just a few.  Noasaurids, specifically were much smaller and more gracile than their relatives, with proportionally small heads and long legs.

The most prominent feature about Masiakasaurus, is its teeth.  Unlike the teeth of most theropods, which angle perpendicular to the jaw, the teeth of Masiakasaurus were angled forward in he front of the mouth.  This striking appearance was what earned its name as "vicious".  Despite its appearance, however, was Masiakasaurus was probably only truly vicious towards much smaller animals.  Its tooth arrangement may have been an adaptation for grasping small, fast moving prey, like a moveable cage.  The environment Masiakasaurus lived in did have many prey animals in it at the time, thanks to a great fossil record from Cretaceous Madagascar, including frogs, mammals, small crocodilians, and even small birdlike dinosaurs.  Another idea that some people have proposed is that Masiakasaurus was a fisher.  In fact, we see similar, unrelated examples of teeth like this in many fish-hunting marine reptiles, like Plesiosaurus.  The teeth in the back of Masiakasaurus' mouth were more similar to those of other theropods, and would have been for cutting food to be swallowed. 

Masiakasaurus skull, featuring the unique teeth and jaws.  CLEARLY it lived during a time before orthodontists.

In addition to its teeth, some other notable features about Masiakasaurus would be its neck, which was long and actually not very flexible, which is not the norm compared to other kinds of long-necked theropods.  Its hands each had four fingers, but only the first three digits on each had claws.

Masiakasaurus skeleton on display at the Royal Ontario Museum in Toronto, Canada.

Masiakasaurus is a great find by paleontology standards because it is known from more than one specimen, so almost all of its anatomy is known.  Another interesting thing about Masiakasaurus, is that paleontologists were able to study what they think was its growth pattern based on individual specimens of different sizes that have been found.  Based on what the pool of specimens available to work with and by closely examining the kind of bones Masiakasaurus had compared to those of other dinosaurs, it is hypothesized that Masiakasaurus was actually a relatively slow-grower, and would have attained adult size by the time it was about eight years old.  This is indeed pretty slow compared to other non-avian dinosaurs that have been studied in the same way and even modern animals that are related to it, like birds, which reach adulthood, in general, much more rapidly.  (Anyone who has ever raised a baby chick knows exactly what I'm talking about.  Seriously, one minute they are fluffy yellow peeps... blink once and BAM...adult chicken.)

That is all for this week!  As always feel free to comment below or on our facebook page!

References

Carrano, M.T.; Sampson, S.D.; Forster, C.A. (2002). "The osteology of Masiakasaurus knopfleri, a small abelisauroid (Dinosauria: Theropoda) from the Late Cretaceous of Madagascar". Journal of Vertebrate Paleontology 22 (3): 510–534.

Carrano, M.T.; Loewen, M.A.; Sertic, J.J.W. (2011). "New materials of Masiakasaurus knopfleri Sampson, Carrano, and Forster, 2001, and implications for the morphology of the Noasauridae (Theropoda: Ceratosauria)". Smithsonian Contributions to Paleobiology 95: 53pp.

Andrew H. Lee & Patrick M. O’Connor (2013) Bone histology confirms determinate growth and small body size in the noasaurid theropod Masiakasaurus knopfleri. Journal of Vertebrate Paleontology 33(4): 865-876.

Sinosaurus: Beast of the Week

This week we will be looking at one of the first large predatory dinosaurs.  Make way for Sinosaurus triassicus!

Sinosaurus triassicus life reconstruction in watercolors by Christopher DiPiazza

Sinosaurus was a meat-eating dinosaur that lived in what is now Southwest China during the early Jurassic period, between 201 and 196 million years ago.  From snout to tail it measured 18 feet (5.5 meters) long. It's genus name translates to "Chinese Lizard/Reptile" and the species name is in reference to the Triassic period which is when it was first believed to have lived upon its discovery. (We now know it was in the Jurassic.)

Sinosaurus is a dinosaur that underwent a few identity changes as paleontologists discovered more fossils and learned more about it over the years.  Most prominently it was believed to be an Asian species of the more popular North American theropod, Dilophosaurus, and was originally named Dilophosaurus sinensis.  This makes sense at first since both of these dinosaurs are known for having two bony crests on the top of their snouts.  They both also even have a similar notch towards the front of their upper jaws.  However, as more material from Sinosaurus was unearthed over the years, it was determined that it was more closely related to later kinds of theropods, called the tetanurans, and therefore was given its own genus name, Sinosaurus.  Tetanurans are a broad group of theropods characterized by how their tails were stiffened in life thanks to how their tail vertebrae interlock together.  Tetanurans are also all more closely related to birds than to other dinosaurs, including other kinds of theropods.  According to this updated idea, Sinosaurus was particularly closely related to another crested theropod from the early Jurassic, Cryolophosaurus.  

Sinosaurus skeletal mount on display at the Maryland Science Center in Baltimore, Maryland, USA.

Sinosaurus had curved serrated teeth that would have been ideal for slicing through and stripping off chunks of meat from bodies.  The upper jaw notch towards the front of its snout may have been an adaptation for hooking into and ripping through the skin of other dinosaurs to get into the meat inside, similar to the hooked beaks of modern carnivorous birds, like hawks, eagles, and vultures.  Sinosaurus is probably most known for its bony crests which adorned the top of its skull.  These crests had holes in them, making them lightweight, and may have served as visual display adaptations within the species or even possibly could have helped absorb impact, allowing Sinosaurus to bite harder without injury.

Sinosaurus skull from in Zhang's 2023 paper. (listed below)

Sinosaurus shows evidence of tooth injury in life in the form of what is called alveolar remodeling.  This means that it experienced a broken tooth and the ridge of bone in the jaw that includes the tooth sockets, called the alveolar bone, changed shape in the healing process following the loss of the tooth.  Dinosaurs losing and replacing teeth is common in the fossil record, but this is the only recorded instance of an actual tooth related injury that healed in this way known so far for a dinosaur.  

Sinosaurus lived during a time when predatory dinosaurs were first starting to get truly large.  Prior to this most meat-eating dinosaurs were much smaller and more gracile, like Coelophysis, and even the biggest plant-eaters, like Plateosaurus, weren't that huge compared to what would later evolve.  At 18 feet long, Sinosaurus was likely the top of the food chain in its environments.  

References

Chung-Chien, Young (1940). "Preliminary Notes on the Lufeng Vertebrate Fossils*: Young:-Lufeng Vertebrate Fossils". Bulletin of the Geological Society of China. 20 (3–4): 235–240.

Dong, Z.M. (2003). "Contribution of New Dinosaur Materials from China to Dinosaurology" (PDF). Memoir of the Fukui Prefectural Dinosaur Museum. 2: 123–131.Xing, L.D.; Bell, P.R.; Rothschild, B.M.; Ran, H.; Zhang, J.P.; Dong, Z.M.; 

Rauhut, O.W.M. (2003). "The interrelationships and evolution of basal theropod dinosaurs". Special Papers in Palaeontology. 69: 215.

Zhang, W.; Currie, P.J. (2013). "Tooth loss and alveolar remodeling in Sinosaurus triassicus (Dinosauria: Theropoda) from the Lower Jurassic strata of the Lufeng Basin, China". Chinese Science Bulletin. 58 (16): 1931–1935.

Zhang, Z.-C.; Wang, T.; You, H.-L. (2023). "A New Specimen of Sinosaurus triassicus (Dinosauria: Theropoda) from the Early Jurassic of Lufeng, Yunnan, China". Historical Biology. in press.