#ichthyosauria

Xiphodracon goldencapensis was an ichthyosaur that lived in marine waters covering what is now the Jurassic Coast of the southern United Kingdom during the Early Jurassic, about 188 million years ago.

Around 3m long (~10'), it had fairly large eyes and a long narrow snout lined with small slender pointed teeth.

It was part of the leptonectid family, closely related to other long-snouted forms like Eurhinosaurus. Although currently only represented by a single fossil specimen, it's actually the most complete ichthyosaur known from the Pliensbachian age of the Early Jurassic.

Preserved gut contents show that it primarily fed on fish, and also that its stomach was positioned on the left side of its body. The fossilized individual also suffered from multiple injuries during its life, including malformed teeth, a fractured clavicle, and avascular necrosis in its upper limb bones. It appears to have died after a bite to the skull from a predator – likely the larger ichthyosaur Temnodontosaurus – and additional bite marks on one hindlimb may be evidence of scavenger activity.

———

NixIllustration.com | Tumblr | Patreon

ftm/transmasc shonisaurus & mtf/transfem majungasaurus !!

i didn't want to link my redbubble on a serious post, sorry

Leninia was a genus of opthalmosaurine ichthyosaur from the Early Cretaceous. Its type species is L. stellans. Its only fossil was found in the bank of the Volga river in Russia. Leninia has the third largest sclerotic ring of any known ichthyosaur, only beat by Baptanodon and Temnodontosaurus.

Leninia is indirectly named after Russian leader Vladmir Lenin, as the museum its fossil is housed in is within the Lenin Memorial and Lenin school complex in Ulyanovsk; as such, the name reflects the fossil's geohistorical location. The species name stellans refers to the fossil's star-shaped frontal-parietal suture.

Its autapomorphies include the presence of an anterior process on the prefrontal over the nasal, a frontal-parietal suture caused by forked processes on both bones, the posterior process of the maxilla extending up to the middle orbit, and the presence of a process on the supratemporal that contacts the parietal.

The only known fossil is a partial skull. It consists of the area from the back of the skull up to the naris, ending in a clean break. Leninia, while being one of the latest-living opthalmosaurines, was recovered as one of the most basal. The presence of a large sclerotic ring and apterure indicates that both are ancestral characteristics of opthalmosaurines, not derived. This also suggests that, unlike Opthalmosaurinae's sister taxon Platypterygiinae, opthalmosaurines did not diversify outside of a "deep diver" niche.

Original paper: Found here

A study of Saurian morphology: Ichthyosauromorpha (part 3)

Cute. Fish. Lizards.

These three genera represent the diversity ichthyosaurs throughout the Jurassic before their numbers declined in Late Jurassic: Temnodontosaurus, known for being one of the larger predatory ichthyosaurs; Excalibosaurus, named after the sword Excalibur for its swordfish-like appearance; and Ophthalmosaurus, famed for its proportionally large eyes which might likely be useful for low-light hunting at night or deeper parts of the ocean.

I’m done with all these daily saurs holy crap. Expect to see the updated phylogenetic tree sometime throughout the week. Also, uploaded this one day early because I’ll be out of town tomorrow.

My next daily project will involve... snails. Blame @cyan-biologist for it.

- - -

A study of Saurian morphology: Ichthyosauromorpha (part 2)

Presenting three early members of Ichthyosauria, With well-developed flippers, early ichthyosaurs were likely to be active warm-blooded animals that breathed air. During the Triassic, they diversified into forms showed above. While the gigantic Cymbospondylus retained serpentine form like its ancestors, many like Mixosaurus evolved into fish-like streamlined figures. Ichthyosaurs also occupied different niches, indicated by the diversity in forms and size. While Mixosaurus was about 1m (3ft) in average, one specimen of Shonisaurus reached as big as 21m (69ft), making it the largest known marine reptile.

Also, holy fish, we’re nearing the end of the project. 3 more fishlizards then I’ll be free!

- - -