coelurosaur

The Bat Hawk (Macheiramphus alcinus) is unique among the raptors for its diet, which consists almost exclusively of bats. It ranges across Sub-Saharan Africa, the Malay Peninsula, Indonesia and New Guinea, and is unmistakable for its appropriately Batman-like dark plumage.

It is a gracile, medium-sized raptor (about 45 cm in length) with a number of adaptations which enable its high-speed-pursuit hunting style.

These proficient and strikingly beautiful hunters are ranked as a Least Concern species.

Pic: by Gary Albert, Sandakan, Malaysia, 2 June 2007 (via Wikimedia Commons)

Sources:  [x] - [x]

All the officially described species of Tyrannosauridea, with the exception
of Tyrannosaurus rex are grouped in this compilation.

Other tyrannosaurid genus have been described like Bagaraatan but they are either too fragmentary
or too dubious and so I decided not to include them.

But this is not the last you will see of this paleo-portrait series, I assure you.

Warning: Those portraits are not to scale.

EDIT: I made a new version of Tarbosaurus’s profile since the first one was relatively innacurate.

EDIT 2: I made new, more accurate versions of Lythronax and juvenile Gorgosaurus.

New Dino-Book of interest incoming!

Dave Hone’s announced the pubblication of “The Tyrannosaur Chronicles”, a book dedicated to the biology and evolutionary history of the famous theropods.
No official print date yet, but expect an early 2016 release. Can’t wait to buy a copy.

Here’s the official announcement: https://archosaurmusings.wordpress.com/2015/07/13/the-tyrannosaur-chronicles/

Blog mention: http://ktboundary-smnt2000.blogspot.it/2015/07/dino-book-of-interest-dave-hones.html

Yi qi, bat-winged dinosaur published today

Yi is a scansoriopterygid, only the third member of this bizarre family of coelurosaur theropods yet discovered. While other scansoriopterygids have very elongate fingers, Yi is the only one know to have supported wing membranes between them. An additional bony prong helps support the wings as well. The authors believe Yi was capable of gliding, though probably not of true powered flight.

Like all known scansoriopterygids, Yi qi is from China. It was discovered in the Tiaojishan Formation, which dates back to the Middle-Late Jurassic, roughly 164 million years ago. Also like the other known members of its group, Yi is tiny. It’s only about the size of pigeon, and that makes it the largest scansoriopterygid yet known.

The Chestnut-flanked sparrowhawk (Accipiter castanilius) is a small, poorly understood accipiter from Central and Western Africa. It is a specialized hunter of small vertebrates, and is commonly found in lowland rainforest habitats.

Pic: by Niall Perrins, Tchimpounga, Republic of Congo, October 2013 (via African Affinity Birding)

Sources:  [x] - [x] - [x]

3

I’ve seen this chart floating around on my dash, and it occurred to me that I never posted the original version. So here is my and Jon‘s Dinosaur Classification Chart, in a hopefully Tumblr-palatable format.

Click here to see the moderately large version at DA.

This is a much simpler examination of dinosaur relationships than most of my watchers would probably find useful. Most of you will know that theropods are broken up into tetanurans and ceratosaurs, and that birds are nested within coelurosaurs, and that there are many internal divisions within sauropods and ornithiscians as well. But this chart is intended to be more of a quick, concise reference for laypeople, teachers, children, or whoever might have a passing interest in dinosaurs. My hope is that anyone who wants to quickly figure out what major group any given dinosaur falls into can glance at this chart and know immediately. 

This was a collaboration between myself and Jon - I did the illustrations, and he did all of the layout and text. To see this chart in full resolution, please consider buying a poster in my Zazzle shop.

A quick Velociraptor mongoliensis, done without references so there are some innacuracies. However, I wanted to reconstruct it with Zhenyuanlong-like plumage since it seems to be the actual default feather arrangement for eudromaeosaurids. Plus, Velociraptor had pretty visible anchor points on its forearms, indicating large wing feathers.

Conchoraptor gracilis . Among the theropods that I draw less frequently, Oviraptorids (and Oviraptorosauria in general) are among the most fascinating coelurosaurs. What amazes me is how much they resemble today’s parrots, especially at the level of the skull. An affinity that seemed even more pronounced when I decided to use the reconstruction by Jaime A. Headden of the oviraptorine Conchoraptor and give it a complete plumage: the resemblance to a lorikeet or a cockatiel is impressive. Because there aren’t any kind of developed cephalic crest, the animal in question seems more than anything else a real parrot  also taking into account the dutiful anatomical precautions.

The main difference between this picture and Headden’s diagrams lies mainly in the positioning of the nostrils. As shown in the study by Lautenschlager et al. the greater extension of the beak of a large part of the rostrum, especially in the area of the premaxilla, involves a repositioning of some structures, like the nostrils, and a radical change in appearance. In this Conchoraptor such ’ innovation ’ is not so obvious, but in the future I will show you that the research in question involves evident iconographic changes on a large scale.

Like for Teratophoneus and Lythronax, because patience is the key to everything, this reconstruction will be undergoing gradual changes. First of all the plumage: even if I’m ‘able’ to paint scaly or bare skin in a more or less 'passable’ way, with a thick layer of fur and/or feathers I still can not get the desired results. Fortunately, there are lots and lots of textbooks and online tutorials (I’ve already found some very good ones), and there’s nothing to do except making more and more exercise and practice.

Also, for the first time in my life, the scanning seems to have even improved the original design. I still can not believe it. It will be the usual fluke.

A Conch Plunderer, 2014.

Coloured with Tria Markers and pencils. Acrylics were used for some light effetcs.

Paper size: A4. Made on Letraset’s Bleedproof Marker Pad.

Loosely based on: brown lory and kea.

References: Jaime A. Headden & “Lautenschlager S, Witmer LM, Altangerel P, Rayfield EJ (2013) Edentulism, beaks and biomechanical innovations in the evolution of theropod dinosaurs. PNAS: 1310711110v1-201310711.”

Links: http://ktboundary-smnt2000.blogspot.it/2014/03/a-conch-plunderer.htmlhttp://smnt2000.deviantart.com/art/A-Conch-Plunderer-442066832

Second part of my Yi Qi variation series.

Since there is no strict consensus about how the wing structure might have looked like, I wanted to show the different models showed in the original paper as well as in other parts of the internet.

EDIT: Now with descriptions and credits ! By intellectual honesty, I decided to credit Smnt2000
as inspiration since he drew a similar concept. And while I had the idea practically at the same time,
I wasn’t the first to finish it. Hence the credit to avoid any claim of plagiarism.

free to reblog. Do not steal.

The discovery of a bat-like dinosaur (well, more like a flying squirrel mimic) was just too exciting, so in this Sketchy Thursday this is what you get: Yi qi studies.

Had a lot of fun with the patagium, experimenting and see how many configurations were possible: ribcage, hip, tail, normal legs, fully feathered legs and so on.
Two different positions were used for the styliform, both of which suggested by the actual fossil.
I know that probably scansoriopterygids didn’t stick out their hindlimbs like bats and pterosaurs, but I’m just very curious to see how it would look like. We’ll see what future findings will tell us.

References: Xu, X.; Zheng, X.; Sullivan, C.; Wang, X.; Xing, L.; Wang, Y.; Zhang, X.; o’Connor, J. K.; Zhang, F.; Pan, Y. (2015). “A bizarre Jurassic maniraptoran theropod with preserved evidence of membranous wings”. Nature. doi:10.1038/nature14423.

“The New Dinosaurs” Review, Part 1

Welcome back to Dinosaur Discourse!  I came back from my break a little bit early, along with that special feature I promised: A series of posts in review of The New Dinosaurs, a book written by Dougal Dixon in the mid-to-late 1980s, and the speculative dinosaur reconstructions therein.

But before we talk about The New Dinosaurs, we have to talk about Dougal Dixon.  Dougal Dixon is a paleontologist, paleoartist, and writer, who is undoubtedly most famous for popularizing the genre of speculative evolution – a form of science fiction that attempts to depict how humans and animals might evolve in the future.  He’s created numerous influential works of speculative evolution, including the books After Man and Man After Man, and was a co-creator of the speculative documentary The Future Is Wild.  He is also, incidentally, a peddler of ludicrous nonsense.

Don’t get me wrong; I’m not calling Dougal Dixon stupid.  He’s a very smart man (and an actual paleontologist, unlike me).  However, he does believe a lot of questionable, outdated, or just plain incorrect things about dinosaurs and their anatomies and evolutionary trends – things that were questionable and outdated even in the 1980s, when The New Dinosaurs was published.

The New Dinosaurs attempts to illustrate how dinosaurs might look today, had the Cretaceous mass extinction never happened.  Unfortunately, as anyone familiar with Dixon’s creations can attest to, they tend to fall into one of two extremes: they are either completely ludicrous and improbable, or they don’t go far enough.  

Every animal depicted in The New Dinosaurs will be assigned a numerary score between 1 and 10, with a score of 1 indicating complete biological implausibility, a 5 indicating a perfect mix of plausible and implausible traits or qualities, and a 10 indicating a highly plausible or probably dinosaur evolutionary descendant.

Now then: Let’s get into the book proper!  (Here’s a link to full scans, if you want to read along.)

Keep reading

I decided to put Blaziken into a cladistic analysis of coelurosaurs (a modified version of the one in Cau’s paper on Balaur). Since all we have is external appearance, only 21 characters could be coded in an analysis of well over 800. This is basically what resulted:

Complete toothlessness, limb proportions, and a shortened tail place it in Pygostylia. It’s kept out of Ornithothoraces by the fact that its fingers have claws and are all around the same length.

The Kagu (Rhynochetos jubatus) is a curious bird native to the montane forests of the French overseas collectivity of New Caledonia. Its placement among the avian family tree has been complicated since the time of its discovery, Once thought to be an ardeid like egrets and herons, it was considered in more recent times to be a gruiform. Of late, it’s usually been allied to the sunbittern of Central and South America, suggesting that the two species may be part of an ancient, Gondwanan radiation of birds.

It’s average-sized so far as ground-dwelling birds go, averaging at around 55 cm long. Strictly carnivorous, its diet consists mostly of invertebrates and small reptiles from the forest floor. Its generic name (‘rhyno’ = nose and 'chetos’ = corn) stems from the 'nasal corns’, a pair of flaps over the nostrils unique to the Kagu among all birds.

It is the heraldic bird of New Caledonia, and despite pressure from introduced mammals which has reduced its range on the island, is the focus of a number of dedicated conservation efforts which have seen considerable success.