#tetanuran

[a-dinosaur-a-day]

Trick or treat!!!🎃🍬

Irritator!

[dinofigureoftheday]

Dino figure of the day: Safari LTD Monolophosaurus

[new-dinosaurs]

Dornraptor normani Baron, 2024 (new genus and species)

(Hindlimb bones of Dornraptor normani, from Baron, 2024)

Meaning of name: Dornraptor = Dornwaraceaster [Anglo-Saxon name for the region roughly corresponding to what is now Dorset] thief [in Latin]; normani = for David B. Norman [British paleontologist]

Age: Early Jurassic (Hettangian–Sinemurian)

Where found: Blue Lias Formation, Dorset, UK

How much is known: A partial hindlimb and a partial femur (thigh bone).

Notes: Fossils of Dornraptor were originally identified in 1859 as specimens of the armored plant-eating dinosaur Scelidosaurus. Later authors thought that they more likely belonged to theropods, but left them unnamed. A new study of these specimens considers them distinct enough to be given a new genus and species. Based on phylogenetic analyses, Dornraptor was probably an early member of Averostra, the group of theropods that unites ceratosaurs and the stiff-tailed tetanurans.

Reference: Baron, M.G. 2024. A new name for old bones: a reassessment of Early Jurassic theropod remains from Dorset, England. Palaeontologia Electronica 27: 25. doi: 10.26879/1346

[paleozoicproductions]

Hell Creek is Real-World Jurassic Park

Jurassic Park features 7 very different dinosaurs throughout the film, Tyrannosaurus, Triceratops, Velociraptor, Brachiosaurus, Dilophosaurus, Gallimimus, and Parasaurolophus. Each animal being significantly different from the other.

What most of the animals have in common is having themselves or standin relatives (or generally standins) living in Hell Creek. For some, it's very obvious, for some, I have to take some very speculative leaps.

Homo sapiens -

No Homo sapiens in Hell Creek! I'm the reference here so, yeah. No humans. It would've been funny to include Purgatorius here but humans weren't cloned for Jurassic Park. Carry on.

Tyrannosaurus -

Tyrannosaurus rex is known from all across western North America, ranging from the south to north. It's range is especially large, and its most well known locality is Hell Creek.

The Tyrannosaurus specimen used was AMNH 5027, the same specimen Jurassic Park used for both its Tyrannosaurus design and its logo. With the in-film size being roughly around 4 meters tall and fairly large, it only somewhat outsizes the actual AMNH 5027 specimen, where the individual is rather 3.6 meters tall and 11.5 meters long.

Triceratops -

Triceratops is a very well known ceratopsian and is prominent across North America, but especially within Hell Creek. The species T. prorsus was intentionally chosen to have an emphasis on the nasal horn. The actual species basis of the film is not stated, but some can assume T. horridus was used only because of it being the type species.

Velociraptor (as Dakotaraptor) -

Dakotaraptor is a large dromaeosaur known from Hell Creek. A lot of its anatomy is highly controversial with it being a potential chimera (beyond the obvious confirmed for the mixed-in turtle material). Because of it, many things cannot be reliably inferred for how it looked and behaved. Some speculation of taking the leg and arm material seriously leads it to be a fairly tall and cursorial-built theropod, adapted for high speeds. The validity of this though is up in the air until more specimens are gathered.

Dakotaraptor was chosen as the standin for Velociraptor mongoliensis due to Jurassic Parks' interpretation of it being a human-height sprinter-type animal found within North America, similar to what potentially Dakotaraptor would've looked somewhat like and behaved.

Brachiosaurus (as Alamosaurus) -

Alamosaurus is a titanosaur that roamed across the North American Ojo Alamo Formation and some nearby locales. Its position in being a Hell Creek sauropod is disputed, with there being a megafaunal barrier between North-South, preventing sauropods like Alamosaurus venturing any further north into Hell Creek. Although some speculation of it venturing in occasionally at some point in history is somewhat likely.

Alamosaurus was chosen as the Brachiosaurus standin only due to it being the nearest North American sauropod to being a Hell Creek sauropod. Brachiosaurids died off in the middle Cretaceous as sauropods generally leaned to extremes of small or large.

Dilophosaurus (as Anzu) -

The biggest reach of this post is Dilophosaurus, since Dilophosaurus and its closest relatives died off in the early-middle Jurassic due to them being an intermediate tetanuran, rather than being part of a surviving lineage.

Anzu fills in the role of a fairly nimble yet taller-than-Dakotaraptor theropod, with a prominent facial crest and potentially predatory diet. Ironically, Anzu is known from smaller specimens and is often undersized, with there being larger specimens out there implying a near 3-metre height.

Gallimimus (as Struthiomimus) -

Struthiomimus is an orninthomimid that lived across North America, often alongside other species of itself and Orninthomimus. It is the largest of the two known orninthomimids in Hell Creek.

Like Gallimimus, Struthiomimus is a highly speedy and sizeable theropod that is a very close relative.

Parasaurolophus (as Lambeosaurinae indet.) -

While Hell Creek has Edmontosaurus annectens, potential unnamed and unpublished material exists that may likely be a Lambeosaurine, adding to the roster of Hell Creek ornithopods. Parasaurolophus itself is a Lambeosaurine and lived in other nearby formations, although earlier in time. The possibility of Parasaurolophus living to end-Maastrichtian in Hell Creek is fairly low but not impossible. Though compared to Alamosaurus, it seems less likely to happen. A safer estimate (and something that would help publicize the idea) would be using the Lambeosaurine indet. as reference.

The Lambeosaurine itself is referenced from Hypacrosaurus and Magnapaulia, two nearby lambeosaurines from very similar timeperiods too. Some adjusted anatomy was used to make it stand out more, as we do not have much of this specimen.

Thank you for reading this very nerdy paleo-blog that helps somewhat justify my chart. Science will change, so the possibilities of this blog changing too (and the artwork) is likely, or just a republished rewritten version. We'll see!!!

Thank you, - Jennifer

[cacatoto-2024]

Cryolophosaurus (/ˌkraɪoʊˌloʊfoʊˈsɔːrəs/ or /kraɪˌɒloʊfoʊˈsɔːrəs/; "CRY-oh-loaf-oh-SAWR-us") adalah sebuah genus dari Theropoda besar yang diketahui hanya dari satu spesies tunggal, Cryolophosaurus ellioti, diketahui dari periode Jura Awal di Antarktika. Panjangnya sekitar 65 meter (213,3 ft) dan beratnya sekitar 465 kilogram (1.025 pon), menjadikannya salah satu theropoda terbesar pada masanya. Individu dari spesies ini bahkan mungkin telah tumbuh lebih besar, karena satu-satunya spesimen yang diketahui mungkin merupakan theropoda yang belum dewasa sepenuhnya. Cryolophosaurus diketahui dari satu tengkorak, satu tulang paha, dan material lainnya, tengkorak dan tulang paha tersebut yang telah menyebabkan klasifikasinya menjadi sangat bervariasi. Tulang pahanya memiliki banyak karakteristik primitif yang mengklasifikasikan Cryolophosaurus sebagai dilophosaurid atau neotheropoda di luar Dilophosauridae dan Averostra, sedangkan karena tengkoraknya memiliki banyak ciri lanjutan, menyebabkan genusnya dikategorikan tetanuran, abelisaurid, ceratosaur, dan bahkan allosaurid. Sejak deskripsi awalnya, konsensusnya adalah bahwa Cryolophosaurus termasuk di antara anggota primitif dari Tetanurae atau kerabat dekat dari kelompok itu.

[ifuckinglovedinosaurssomuchjesus]

An interesting little guy, when it was first described this little feathery fluffball made big waves because the descriptors classified it as a Megalosaur, the group of dinosaurs that contains the likes of Torvosaurus and Spinosaurus. This was a big deal because Megalosaurs are on the Carnosaur side of the theropod family tree, making it pretty far away from the bird-like dinosaurs, further suggesting feathers are something that's been around on dinosaurs for a lot longer than previously suspected.

However that was quickly contested and new studies placed it as a Compsognathid, a group of small nippy little carnivores well established to be fluffy and bird-like, so Sciurumimus' 15 minutes of fame was over and it's uniqueness deemed as typical.

Now, however, some scientists are putting forward the idea that Compsognathids don't even exist. What we thought were shared characteristics of similarly related animals may in fact be similarities between juveniles. Think how baby mammals all have the same big heads and eyes and chubby little bodies even when they're completely unrelated. Sure enough, most Compsognathid specimens known are not fully grown. If this is true than it throws a wrench in that whole group and the Compsognathids, instead of their own species, could be the scattered babies of dinosaurs across the family tree.

Studies of where Sciurumimus fits exactly are still in the works, but the latest puts it as a baby of a basal tetanuran, giving it back what made it famous in the first place. Does this mean baby theropods being fluffy little critters with big poofy tails was a universal consistent? Only time will tell.

Sciurumimus albersdoerferi

Holotype specimen

Source

[skyland2703]

Tetanuran dinosaurs, a group in Theropoda enclosing of Coelurosauria and Carnosauria, likely could not taste spicy flavors as modern day birds are incapable of tasting spicy.

It’s technically possible for a blood transfusion between a Gallimimus and a Tyrannosaurus since there was a successful blood transfusion between a hawk and a pigeon.

Brain go BRRRRRRRRRRR

I actually like the the no spicy dinosaurs. I would’ve loved to inherit those genes because i for one can NOT tolerate spice.

The… the second one……….

What the fuck Hesploro.

[actual-haise]

Ringing in the new year with some new paleoart of a newly discovered (well, December 2019) species: The basal allosauroid Asfaltovenator! It might seem like a standard theropod, but it's basal position may really shake up phylogeny.

[dracontes]

Stern Allosaur by dracontes

[rmyers08]

Day 2: Tranquil ... #inktober #inktober2018 #tranquil #mesozoic #jurassic #dinosaur #theropod #tetanuran #allosaurus #chillin #ink #doodle #artistsoninstagram https://www.instagram.com/p/Boc_YBsFdmA/?utm_source=ig_tumblr_share&igshid=3ayll8ghaql4

[dinosaurs-dinosaurs-dinosaurs]

Image from Mark Witton, drawn by Mark Witton

B is for Baryonyx!

Baryonyx is a Spinosaurid from England. It evolved a crocodile-like snout for catching fish, as well as large claws on its hands to hook them out of the water! Though smaller than Spinosaurus, the two were closely related. 

[a-dinosaur-a-day]

Trick or treat! 🦒

Sinraptor!

[goldenchocobo]

Dinovember Day 14- Tetanuran - Monolophosaurus

[new-dinosaurs]

Qianlong shouhu Han et al., 2023 (new genus and species)

(Select bones and schematic skeletals of adult [a] and embryonic [b] individuals of Qianlong shouhu, with preserved bones in gray, from Han et al., 2023)

Meaning of name: Qianlong = Qian [alternative name for Guizhou] dragon [in Chinese]; shouhu = guarding [in Chinese]

Age: Early Jurassic (Sinemurian?)

Where found: Ziliujing Formation, Guizhou, China

How much is known: Three partial skeletons of adult individuals and five clutches of 3–16 eggs containing embryos.

Notes: Qianlong was an early sauropodomorph. It is notable not only for the exceptional preservation of its fossils, but also the fact that these specimens appear to be associated with nests, thus offering valuable information on their growth and reproductive behavior. As has also been found for some early sauropodomorphs, such as Massospondylus from the Early Jurassic of Southern Africa and Mussaurus from the Early Jurassic of Argentina, Qianlong appears to have laid its eggs in breeding colonies with adult individuals potentially watching over their nests. Qianlong was additionally similar to these other early sauropodomorph in being bipedal as an adult, but likely quadrupedal as a young juvenile.

Rigid, hard-shelled eggs have been found in multiple groups of dinosaurs, including tetanuran theropods (such as birds), hadrosaurids (duck-billed dinosaurs), and titanosaurian sauropods, as well as their closest living relatives, the crocodylians. As a result, it was long assumed that all dinosaurs probably laid hard-shelled eggs. However, recent evidence has suggested that the eggs of early dinosaurs may have instead had flexible, leathery shells, more similar to those of most lizards and some turtles, with rigid eggshells evolving several times in later dinosaur groups. The eggshells of Qianlong appear to have been leathery in structure, lending support to this hypothesis.

Reference: Han, F., Y. Yu, S. Zhang, R. Zeng, X. Wang, H. Cai, T. Wu, Y. Wen, S. Cai, C. Li, R. Wu, Q. Zhao, and X. Xu. 2023. Exceptional Early Jurassic fossils with leathery eggs shed light on dinosaur reproductive biology. National Science Review advance online publication. doi: 10.1093/nsr/nwad258

[typhlonectes]

Subaqueous foraging among carnivorous dinosaurs 

Matteo Fabbri, Guillermo Navalón, Roger B. J. Benson, Diego Pol, et al.

Abstract

Secondary aquatic adaptations evolved independently more than 30 times from terrestrial vertebrate ancestors. For decades, non-avian dinosaurs were believed to be an exception to this pattern. Only a few species have been hypothesized to be partly or predominantly aquatic. However, these hypotheses remain controversial, largely owing to the difficulty of identifying unambiguous anatomical adaptations for aquatic habits in extinct animals. 

Here we demonstrate that the relationship between bone density and aquatic ecologies across extant amniotes provides a reliable inference of aquatic habits in extinct species. We use this approach to evaluate the distribution of aquatic adaptations among non-avian dinosaurs. We find strong support for aquatic habits in spinosaurids, associated with a marked increase in bone density, which precedes the evolution of more conspicuous anatomical modifications, a pattern also observed in other aquatic reptiles and mammals. 

Spinosaurids are revealed to be aquatic specialists with surprising ecological disparity, including subaqueous foraging behaviour in Spinosaurus and Baryonyx, and non-diving habits in Suchomimus. Adaptation to aquatic environments appeared in spinosaurids during the Early Cretaceous, following their divergence from other tetanuran theropods during the Early Jurassic.

Read the paper here:

https://www.nature.com/articles/s41586-022-04528-0

[albertonykus]

What do you think of Cau’s hypothesis that compsognathids are juvenile carnosaurs?

His hypothesis is not so much that all compsognathids are juvenile carnosaurs (though in one of his blog posts he acknowledged the possibility that they could be), but that at least some specimens that have been assigned to Compsognathidae might have been juveniles of larger tetanurans (not just carnosaurs, as he has speculated that a few could have been juveniles of larger coelurosaurs). As far as that goes, I think the idea is quite plausible. I strongly suggest reading Cau’s original paper as well as his two blog posts on the subject, as there appear to be many misconceptions going around about what he actually said.