#therocephalian

Another #paleostream sketch

Choerosaurus, a funny guy, look at its bumpy face!

Euchambersia was a therapsid - early relatives of mammals - from the Late Permian of South Africa. Ridges on its canine teeth and indentations at the sides of its skull have led some scientists to hypothesize it was venomous.

By Ripley Cook

Etymology: Crocodile from Oliviershoek Pass

First Described By: Brink, 1965

Classification: Biota, Archaea, Proteoarchaeota, Asgardarchaeota, Eukaryota, Neokaryota, Scotokaryota, Opimoda, Podiata, Amorphea, Obazoa, Opisthokonta, Holozoa, Filozoa, Choanozoa, Animalia, Eumetazoa, Parahoxozoa, Bilateria, Nephrozoa, Deuterostomia, Chordata, Olfactores, Vertebrata, Craniata, Gnathostomata, Eugnathostomata, Osteichthyes, Sarcopterygii, Rhipidistia, Tetrapodomorpha, Eotetrapodiformes, Elpistostegalia, Stegocephalia, Tetrapoda, Reptiliomorpha, Amniota, Synapsida, Eupelycosauria, Metopophora, Haptodontiformes, Sphenacomorpha, Sphenacodontia, Pantherapsida, Sphenacodontoidea, Therapsida, Eutherapsida, Neotherapsida, Theriodontia, Eutheriodontia, Therocephalia, Scylacosauria, Eutherocephalia, Akidnognathidae

Status: Extinct

Time and Place: Olivierosuchus lived 251 to 249 million years ago, in the Olenekian of the Early Triassic.

Olivierosuchus is only known from South Africa.

Physical Description: I feel like most of you would look at Olivierosuchus and think “that’s a good pupper”. Olivierosuchus had a fairly long snout that was slightly wider than deep. The snout has a slight upwards bend and has small pits that indicate the presence of whiskers. It had three types of teeth: average-sized incisors, a pair of large canine teeth, and small teeth in the back of the jaw. The body was low-slung and may have had semi-sprawling forelimbs. Its forelimbs were robust and were likely adapted for digging. Olivierosuchus had whiskers, and may have had a more extensive covering of fur.

Before you ask - Olivierosuchus was not venomous like has been suggested for its relative Euchambersia. Its teeth do not have grooves for spreading venom.

Diet: Olivierosuchus was carnivorous, and fed on smaller animals like parareptiles and the young of other synapsids.

Behavior: First - burrows can preserve in the fossil record, and it’s really interesting. Such as one large, wide burrow preserved in early Triassic rocks from South Africa. Interestingly, this burrow has the skeleton of a juvenile Lystrosaurus inside. The Lystrosaurus was too small to dig the burrow, but it’s the perfect size for something like Olivierosuchus. So an Olivierosuchus probably lived in the burrow, and brought back a dead Lystrosaurus juvenile as food. The back teeth of therocephalians suggests they may have been able to chew their food a bit before swallowing it. This is in contrast to gorgonopsians, which were forced to tear off swallowable chunks of food.

Ecosystem: Olivierosuchus lived alongside Lystrosaurus, because of course it did, everything alive at the beginning of the Triassic lived alongside Lystrosaurus. In fact the specific rock layer it was found in - which was deposited immediately after the Permian-Triassic Extinction - is called the Lystrosaurus Assemblage Zone. The environment was arid and not exactly lush, because of the extinction that just happened. The biostratigraphy of the Lystrosaurus Assemblage Zone is well-mapped enough that we know which therocephalians lived at exactly the same time as Olivierosuchus: those being Moscorhinus, “Tetracynodon” darti, Ericolacerta, Regisaurus, and Zorillodontops. The Lystrosaurus Assemblage Zone is also known for lots of Procolophon and Sauropareion, as well as cynodonts such as Thrinaxodon and Galesaurus. Early archosaurs are also known, such as Prolacerta and Proterosuchus, as well as temnospondyls like Broomistega and Lydekkerina.

Other: Olivierosuchus was originally named Olivieria by A.S. Brink in 1965. It was renamed Olivierosuchus in 2002 by Christian Kammerer and Christian Sidor, because Olivieria was already taken by a fly.

~ By Henry Thomas

Sources under the cut

Gorynychus masyutinae • A New Therocephalian from the Permian Kotelnich Locality, Kirov Region, Russia

A new therocephalian taxon (Gorynychus masyutinae gen. et sp. nov.) is described based on a nearly complete skull and partial postcranium from the Permian Kotelnich locality of Russia. Gorynychus displays an unusual mixture of primitive (“pristerosaurian”) and derived (eutherocephalian) characters...

By ‘on the cast rotation’ I assume you mean Rex, Sid and Nancy, right?

Well, generally, pretty much my all-time favourite prehistoric creatures are probably Mammoths and Smilodons