Archosaurophilia

https://archosaurophilia.blogspot.com/ - Essentially, a long-winded love letter to Archosauria (Cope, 1869) ... with digressions.

[archosaurophilia]

Life in the Age of Pterosaurs

Tethydraco from Apple TV+'s Prehistoric Planet . If you grew up with BBC's landmark documentary Walking With Dinosaurs like I did , you m...

I was inspired by the impressive diversity of pterosaurs that I recently saw in Prehistoric Planet to write this post. The last of the pterosaurs were more diverse than we could have imagined a few decades ago, and it is my hope that this post will serve to paint you a picture of the world that they lived in.

[archosaurophilia]

Ten years later - Thoughts and reflections

  Once again... a male Andean condor ( Vultur gryphus ) photographed at the Cincinnati Zoo by Greg Hume. Retrieved via Wikimedia Commons . O

Archosaurophilia is now ten years old! Here are my brief thoughts on this milestone over on the main blog.

[archosaurophilia]

Leaping Lagerpetids, and other updates

I've long considered the Triassic to be the most fascinating period in Earth's history (aside from, perhaps, our own). As well as being a crucial period in understanding the history of Earth's ecosystems and recovery from extinction events, the Triassic has always had an allure and mystery to me, owed in part to its enigmatic, almost alien animals. Researchers have likewise been confounded by many mysteries relating to the Triassic over the years, including the origin of ornithischian dinosaurs. The origins of another group at roughly the same time have proved equally enigmatic: the pterosaurs, yet again.

[archosaurophilia]

Leaping Lagerpetids, and other updates

I've long considered the Triassic to be the most fascinating period in Earth's history (aside from, perhaps, our own). As well as being a crucial period in understanding the history of Earth's ecosystems and recovery from extinction events, the Triassic has always had an allure and mystery to me, owed in part to its enigmatic, almost alien animals. Researchers have likewise been confounded by many mysteries relating to the Triassic over the years, including the origin of ornithischian dinosaurs. The origins of another group at roughly the same time have proved equally enigmatic: the pterosaurs, yet again.

[archosaurophilia]

Leaping Lagerpetids, and other updates

I've long considered the Triassic to be the most fascinating period in Earth's history (aside from, perhaps, our own). As well as being a crucial period in understanding the history of Earth's ecosystems and recovery from extinction events, the Triassic has always had an allure and mystery to me, owed in part to its enigmatic, almost alien animals. Researchers have likewise been confounded by many mysteries relating to the Triassic over the years, including the origin of ornithischian dinosaurs. The origins of another group at roughly the same time have proved equally enigmatic: the pterosaurs, yet again.

[thek560]

Dead Carcharodontosaurus, digital painting.

Support me on Patreon

Merch available on Redbubble

[mutant-distraction]

Sunbittern.

📸: Dusan Brinkhuizen.

[oneweirdreptileaday]

Unaysaurus tolentinoi

[birdblues]

Black-and-white Warbler

[new-dinosaurs]

Meraxes gigas Canale et al., 2022 (new genus and species)

(Select bones and schematic skeletal of Meraxes gigas [scale bars = 10 cm for individual bones and 1 m for the skeletal], with preserved bones in white, from Canale et al., 2022)

Meaning of name: Meraxes = dragon character from the A Song of Ice and Fire novel series; gigas = giant [in Greek]

Age: Late Cretaceous (Cenomanian–Turonian)

Where found: Huincul Formation, Neuquén, Argentina

How much is known: Partial skeleton of one individual, including a nearly complete skull and limbs.

Notes: Meraxes was a carcharodontosaur, a group of large, carnivorous theropods that also includes Giganotosaurus and Acrocanthosaurus. It was probably closely related to other South American carcharodontosaurs like Giganotosaurus, Mapusaurus, and Tyrannotitan. These genera were among the largest known theropods, all of them (including Meraxes) having been estimated to have weighed over 4 tons.

Meraxes exhibits the most completely preserved skull and forelimbs of any carcharodontosaur discovered. Its forelimbs were greatly reduced in size, comparable in relative length to those of the famously short-armed tyrannosaurids. However, even though carcharodontosaurs had convergently evolved a similar body plan to tyrannosaurids, microscopic examination their bone structure indicates that these two groups of large theropods grew in very different ways. Whereas giant tyrannosaurids reached their adult sizes by going through a growth spurt relatively early in life, Meraxes grew more slowly across a longer period of time. In fact, the type specimen of Meraxes is inferred to have been between 39–53 years old when it died, making it the oldest individual of a Mesozoic theropod known so far.

Reference: Canale, J.I., S. Apesteguía, P.A. Gallina, J. Mitchell, N.D. Smith, T.M. Cullen, A. Shinya, A. Haluza, F.A. Gianechini, and P.J. Makovicky. 2022. New giant carnivorous dinosaur reveals convergent evolutionary trends in theropod arm reduction. Current Biology advance online publication. doi: 10.1016/j.cub.2022.05.057

[allblackbirds]

Common Starling (Sturnus vulgaris)

© Simon Richards

[sixth-extinction]

At one time, the Eskimo curlew or northern curlew (Numenius borealis) may have been the most abundant shorebird in North America. In the late 1800′s, about two million of these birds were killed per year, and they quickly became very scarce.

The last known Eskimo curlew was killed in Barbados in 1963, though occasional unconfirmed sightings have been reported since then. It is officially classified by the IUCN as critically endangered, but was likely extinct by the late 1960′s. If any survive, the population is likely tiny, numbering 50 or fewer individuals.

Top image: A mounted specimen at the Field Museum in Chicago. [x] Second image: Photograph of a live Eskimo curlew taken on Galveston Island in 1962. [x] Third image: The Smithsonian Institution’s collection of 16 Eskimo curlew specimens. [x]

[birdstudies]

June 13, 2022 - Trinidad Motmot (Momotus bahamensis)

These large motmots are found only in Trinidad and Tobago in rainforests, cacao plantations, beaches, pastures, and gardens. They eat insects, spiders, mollusks, and earthworms, as well as some small reptiles, young birds, and fruits, foraging alone or in pairs from low perches. Pairs nest in burrows in banks, where both parents incubate the eggs.

[birdblues]

Green Magpie

[thek560]

A few dinosaurs. Baryonyx, Psittacosaurus, Deinonychus, Concavenator, Triceratops, Styracosaurus, Allosaurus and Gallimimus.

Support me on Patreon

Merch available on Redbubble

[candela888-deactivated20250324]

Countries Tyrannosaur fossils have been found in 🦖

[i-draws-dinosaurs]

While this map isn’t strictly wrong, it’s missing a lot of detail that I would like to fill in! “Tyrannosaur” isn’t a very clear term scientifically, so we’re going to take a look at the geographic ranges of both the famous giants in the Tyrannosauridae, and the range of the wider group Tyrannosauroidea! Also I made some maps because maps are cool and I like them. The base map is from Wikimedia Commons.

Tyrannosaurids are what you’d usually think of when you think “tyrannosaur”. most of them were huge, powerful predators that lived towards the end of the Cretaceous. Their actual geographic range was somewhat limited though, having only been found in Asia and North America.

ID: A map of the world with some countries coloured red, indicating that Tyrannosaurid species have been named from these locations. The red countries are: Canada, which includes Albertosaurus, Daspletosaurus, Gorgosaurus, and Tyrannosaurus. The United States, which includes Daspletosaurus, Dynamoterror, Gorgosaurus, Lythronax, Teratophoneus, Thanatotheristes, and Tyrannosaurus. China, which includes Qianzhousaurus, Tarbosaurus, and Zhuchengtyrannus. Mongolia, which includes Alioramus and Tarbosaurus. End ID.

Occasional dislocated teeth have been found in Mexico and Kazakhstan, which might be what the original map refers to, but I have chosen to exclude them as they are not good enough material to reliably assign to a species.

On the other hand, we have Tyrannosauroidea, a larger group that includes the giant Tyrannosaurids as well as a wide variety of medium sized and smaller transitional forms, and strange groups like the Proceratosaurids which have a thin crest on their snouts! Since this group covers more of the evolutionary background of the Tyrannosaurids, Tyrannosauroid fossils are more widespread.

ID: A map of the world with some countries coloured red to indicate the presence of Tyrannosauroid dinosaurs. The red countries include: The United States, which includes Nanuqsaurus in Alaska, and Appalachiosaurus, Bistahieversor, Daspletosaurus, Dryptosaurus, Dynamoterror, Gorgosaurus, Lythronax, Moros, Stokesosaurus, Suskityrannus, Teratophoneus, Thanatotheristes, Tyrannosaurus, and possibly Tanycolagreus. Canada, which includes Albertosaurus, Daspletosaurus, Gorgosaurus, and Tyrannosaurus. Portugal, which includes Aviatyrannus. The United Kingdom, which includes Eotyrannus, Juratyrant, and Proceratosaurus. Russia, which includes Kileskus. Uzbekistan, which includes Timurlengia. China, which includes Alectrosaurus, Dilong, Guanlong, Jinbeisaurus, Qianzhousaurus, Sinotyrannus, Tarbosaurus, Xiongguanlong, Yutyrannus, and, Zhuchengtyrannus. Mongolia, which includes Alioramus, Bagaraatan, and Tarbosaurus. Some countries have been coloured with a red halftone, these countries are Mexico which includes Labocania, Brazil which includes Santanaraptor, and Australia which includes Timimus. End ID.

I’ve excluded from this map any nomen dubia, species named after an insufficient amount of material since they are often very difficult to assign to any particular group. I also coloured some of these countries with a red halftone, which is to indicate species that are scientifically valid, but may or may not be members of Tyrannosauroidea. As with a lot of palaeontology, there’s some grey area here that I feel is worth representing!

So yeah, those are my Tyrannosauroid and Tyrannosaurid maps! Hope this has taught you something new!

[birdsagainstgravity]

White-booted Racket-tail (Ocreatus underwoodii)

© Jean-Luc Baron