Vectispinus

Credit: Anthony Hutchings.

The White Rock Spinosaurid, formerly known as "Vectispinus", is an indeterminate genus of large Baryonychinae spinosaurid that lived in England during the Early Cretaceous.

## History

The spinosaurid fossils were discovered the late local collector Nick Chase, who gave the specimens to Jeremy Lockwood when he was ill, asking him to describe and publish them. It is estimated to be 13.1 meters in length, which is very large for a baryonychine. This would make Vectispinus the largest theropod dinosaur known from Europe. Thomas R. Holtz Jr. agrees with the conclusions presented by the study despite being uninvolved. It is from the Vectis Formation, a Barremian-Aptian formation that is the youngest of the Wealden Supergroup, with this individual dating to ~125 million years. At discovery, it was the youngest spinosaur from Britain, which the describers hope to be diagnostic enough to name. Matrix on the remains suggest that they were unearthed during a single cliff-fall. During press runs from Barker et al. (2021)'s publication, they teased additional spinosaur fragments at the exposition. Darren Naish posted them to his Twitter with the remains censored. Still, the name “Vectispinus” does exist as the White Rock Spinosaurid’s title.

## Description

It is known from an anterior dorsal, 2 fused sacrals (IWCMS 2018.30.2), an anterior caudal (IWCMS 2018.30.3), fragmented ribs, pelves parts, long bone fragments and some additional vertebral material. They are all exceptionally large, indicating such a large size, and a combination of size consistency and close proximity suggest that they are of the same individual. The initial describers knew that the remains were of a tetanuran when work first started based on the bones being pneumatic, opisthocoelus form on the anterior caudal, laminae and the possible posterior ilium part has a brevis fossa. They ruled our identification as a sauropod based on a plethora of morphological traits, using synapomorphies such as 'webbing' at the base of the neural spine (unique to Spinosauridae) and a flat ring at the anterior articular face (unique to Megalosauroidea). They did not find any specific traits that indicate that it is from an already-named genus and, at some times, considered the name "Vectispinus", but did not because there are no autapomorphies and it is fragmentary, although they were reasonably sure that it was distinct. The vertebral centra are ~16 centimeters long, on par with or larger than *Spinosaurus*.

## Classification

The presence of centrodiapophyseal lamina, prezygodiapophyseal lamina and deep prezygocentrodiapophyseal fossa suggest spinosaurine affinities, which would match with the massive size. They modified Barker et al. (2021)'s dataset to include this taxon, and is sometimes recovered as a spinosaurine and other times is outside of any subfamily.

## Paleoecology

It was contemporaneous with *Mantellisaurus* and *Polacanthus*, but ichnites and the possibility of new discovery suggest a much more diverse ecosystem. This environment would have had many narrow river channels meeting a lagoon.

## References

* https://www.france24.com/en/live-news/20220609-europe-s-largest-predatory-dinosaur-found-by-uk-fossil-hunter?ref=tw
* https://metro.co.uk/2022/06/09/remains-of-europes-largest-land-based-dino-found-on-the-isle-of-wight-16797211/
* https://www.theguardian.com/science/2022/jun/09/fossils-found-isle-of-wight-may-be-from-largest-spinosaur-in-europe
* https://news.sky.com/story/largest-ever-land-based-predator-dinosaur-found-on-the-isle-of-wight-12630674
* https://twitter.com/TomHoltzPaleo/status/1534888450469543943
* https://www.reuters.com/lifestyle/science/europes-largest-meat-eating-dinosaur-found-isle-wight-2022-06-09/
* https://www.itv.com/news/meridian/2022-06-09/remains-of-europes-largest-ever-land-predator-dinosaur-found-on-isle-of-wight
* https://tetzoo.com/blog/2022/6/8/giant-spinosaurid-dinosaur-from-the-isle-of-wight
* https://twitter.com/valdosaurus/status/1534861120732798978
* https://theropoddatabase.com/Megalosauroidea.htm