"Beautiful" Squirrel-Tail Dinosaur Fossil Upends Feather Theory

A newfound squirrel-tailed specimen is the oldest known meat-eating dinosaur with feathers, according to a new study. The late-Jurassic discovery, study authors say, strikes down the image of dinosaurs as “overgrown lizards.”

Unearthed recently from a Bavarian limestone quarry, the “exquisitely preserved” 150-million-year-old fossil has been dubbed Sciurumimus albersdoerferi—"Scirius" being the scientific name for tree squirrels.

Sciurumimus was likely a young megalosaur, a group of large, two-legged meat-eating dinosaurs. The hatchling had a large skull, short hind limbs, and long, hairlike plumage on its midsection, back, and tail.

“I was overwhelmed when I first saw it. Even apart from the preservation of feathers, this is certainly one of the most beautiful dinosaur fossils ever found,” Read more.

“Savage lizard”
Late Jurassic, 153-148 million years ago

This “savage lizard” could grow up to 33 feet in length, making it one of the largest predators of the Jurassic! Two separate species have been found, one in Colorado and one in Portugal. If that seems unnecessarily specific, it’s important to remember that 150 million years ago, Colorado and Portugal were ever so slightly less nowhere-near-each-other. Yeah, still weird.

Here we go with a personal take of the Brazilian spinosaurid Irritator. And yes, it is feathered. Please, leave me alone.

Irritator is a genus of spinosaurid dinosaur that lived in the early Cretaceous Period (Albian stage), around 110 million years ago. Current estimations indicate a length of 8 meters and a weight of 2-3 tons. It was found in Brazil. Irritator was a theropod with an unusually shaped crest at the rear of its head, and probably ate fish. So far the only fossil that has been found was an 80 centimeter long fossil skull in the Romualdo Member, a layer member of the Brazilian Santana formation. This skull strongly resembles the skulls of Suchomimus and Spinosaurus. The genus is often regarded today as identical (synonymous) with Angaturama, which lived in the same time and the same place as Irritator.

Irritable, 2012.

Coloured with Tria Markers and pencils. Based on grey headed and Campbell albatrosses

References: Felipe A. Elias


The Piatnitzky’s lizard, Piatnitzkysaurus (1979)

Phylum : Chorata
Class : Reptilia
Order : Saurischia
Suborder : Theropoda
Superfamily : Megalosauroidea
Family : Piatnitzkysauridae
Genus : Piatnitzkysaurus
Specie : P. floresi

  • Middle Jurassic (164 - 161 Ma)
  • 4,3 m long and 450 kg (size)
  • Cañadon Asfalto formation, Argentina (map)

The holotype specimen of Piatnitzkysaurus, PVL 4073, was collected during expeditions in 1977, 1982, 1983 at the Canadon Asfalto Formation in sediments that were deposited during the Callovian stages of the Jurassic period, approximately 164 to 161 million years ago. Once thought to be a basal carnosaur, it may instead be a megalosauroid. In total two partial skeletons are known and show that Piatnitzkysaurus was a relatively lightly built medium-sized bipedal carnivore that was around 4.3 metres long and around 450 kilograms in mass, though such estimates apply to the holotype, which is a subadult. It had robust arms and powerful hind legs with four toes on each foot. Its ischium is 423 millimetres long. Its braincase resembles that of another megalosauroid, the megalosaurid Piveteausaurus from France. A general resemblance to the theropod Allosaurus was also noted by Benton (1992).


Quite Possibly the Cutest (Accurate) Dinosaur Illustration Ever
Annalee Newitz

Science artist Emily Willoughby specializes in birds and their feathery ancestors among dinosaurs. And in this illustration, “The Rains of Rogling,” is possibly the cutest scientifically accurate rendition of a dinosaur I’ve ever seen. It probably helps that this is a picture of a baby, and (yes) it’s covered in down. It’s like the Cretaceous version of a kitten. Writes Willoughby:

Here is my rendition of the purported baby megalosauroid, Sciurumimus, perched on a rock by the Bavarian sea as it waits patiently for its mother to return to it. Two pterodactylid pterosaurs comb the beach in the background. From the late Jurassic Rögling Formation of Germany, ~150 mya.

You can see more of Willoughby’s incredible work on her site.

Dinosaur POOP!

A coprolite or coprolith is a type of trace fossil formed from feces. The word coprolite comes from the Ancient Greek word κόπρος (kopros) meaning dung and λίθος (lithos) meaning stone. The word was coined in 1829 by no less than William Buckland, the man who ‘discovered’ and systematically named the first dinosaur, the Megalosaur. Buckland was aided by Mary Anning, a self-taught paleontologist who sold fossils as part of a family business. Mary would spend winters scouring the cliffs of Southern England around her home in Dorset, risking her life as the cliffs would often collapse, once even killing her dog. Mary is credited with the discovery of the first icthyosaur, a find she made while collecting with her brother when she was only 12 years old. It was her collection of coprolites that led Buckland to his identification as feces. Coprolites are important trace fossils as they allow scientists to glimpse at the diets of ancient creatures.  Finally, Happy Birthday do William Buckland, born on March 12, 1784!  Your fascination with dinosaur poop has earned your place in history!

Image of Great White Shark coprolite from Miocene Era and yucky orange poopy coprolites both  courtesy James St. John; Box of poop courtesy Paul Williams; flattened poop coprolite courtesy paleo-bear, all used with permission under a Creative Commons 3.0 license.

Weird Backs Month #25 – Ichthyovenator

We’re coming up on the end of the month now, and we can hardly talk about weird backs without looking at the spinosaurs, can we? Part of the megalosaur branch of the theropods, these dinosaurs had specialized croc-like skulls and seem to have led semi-aquatic lifestyles similar to those of modern crocodiles or hippos – and, of course, they’re most famous for the eponymous giant sailbacked Spinosaurus, who’ll be featured in a couple of days.

Ichthyovenator here lived during the Early Cretaceous of Laos (~125-112 mya), and was probably around 8m in length (26′2″). Although it was originally thought to be a close relative of Baryonyx, more recent discoveries of additional material (currently unpublished) suggest it might be much closer to Spinosaurus.

It had an unusual-looking “double sail”, with  a distinct notch in the elongated vertebrae over its hips. The neural spines were much shorter and proportionally wider than those of Spinosaurus, however, and the structure may have been more of a ridge or hump than an actual sail.