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Finally a new upload! I know this is coming about a month too late, but I hope y'all had a merry christmas and a happy new year. Anyways, regarding art the last few weeks or so haven't been the most productive for me, but since I want to add a new image to my gallery somewhat regularly (at least once a month) I put together this.

This portrait depicts Oxalaia quilombensis, a very fragmentary Brazilian spinosaurine theropod from the Cenomanian stage of the Late Cretaceous (95-ish million years ago) of Cajual Island in the North East of the country. The species name derives from the quilombolas people who inhabit the island, while the genus name refers to Oxalá, the Brazilian version of the African god Obatala (introduced to South America by escaped slaves who also founded the quilombo settlements).

First discovered in 1999 by paleontologists of the National Museum in Rio de Janeiro, Oxalaia remained unstudied for many years until being formally tackled by Aleander Kellner and collegues in 2011. As already noted, the fossil material that the description and erection of this taxon is based on is pretty fragmentary (so fragmentary in fact, that this reconstruction features all of what is known). The holotype is represented by the tip of the snout (fused premaxillary bones) and the small part of a left maxilla that was also attributed to this dinosaur despite being found isolated from the rest. Several spinosaur teeth as well as vertebrae (all labelled as Bahariyasaurus) found in the same region may also come from Oxalaia, although there is no way to say this for certain.

Although even with the known remains being far from complete, some unique traits could be identified that according to the authors justify the classificication as a new genus and species. Not all paleontologists agree with this.Following this alternative view the Oxalaia.specimens would fall under Spinosaurus (maybe under S. aegyptiacus or as ist own species S. quilombensis? The taxonomy of the African spinosaurines is also quite messy by the way) and the differences between those two could be explained as examples of individual variation. Due to the incomplete nature of Oxalaia this is a hard question to properly answer and unfortunately any chance of working with the original material may have been lost. In 2018 there was a big fire at the museum in Rio de Janeiro that many fossils housed in the building didn't survive. The bones of the enigmatic Oxalaia are possibly among them.

So in terms of overall appearence Oxalaia would have most likely pretty much resembled Spinosaurus, even if classified as a distinct dinosaur. Studies have recovered it as the closest known relative of the famous sailback from Africa. The presence of another slightly older spinosaurine in Brazil called Angaturama (which some incidentally view as a junior synonym of Irritator) suggests that there was a strong biogeographic connection between the continents of Western Gondwana as they were connected until the Late Lower Cretaceous. Even in the Early Upper Cretaceous, at the time when Oxalaia and Spinosaurus roamed, Northern Africa and South America (or at least Cajual Island) would have probably been linked by some sort of island chain or something similar.

The Alcântara Formation, the home of Oxalaia would been heavily vegetated and fairly humid, even though adjacent regions were probably much dryer. Contemporaries of the spinosaur include rebbachisaurids, titanosaurs, various theropods such as noasaurids, carcharodontosaurs, dromaeosaurids and even fellow spinosaurids, crocodile-relatives and lots of fish (featuring some big ones which would have been part of Oxalaia's diet among other creatures). This assemblage shares quite many resemblences to the ones uncovered in similarly aged rocks in North African countries.

In terms of integument I tried to make the snout appear somewhat hardened or "toughened" because this is a body part that would have been especially subjected to the environment through activities such as hunting, inter- and intraspecific combat or generally coming into contact with surrounding stuff. I also decided to add a considerable amount of extra oral tissue. I've noticed that there are different approaches for spinosaurs when it comes to this topic. Some reconstructions show them with exposed teeth (somewhat similar to crocodiles) while in others only the teeth in the front of the closed mouth are visible. However, I went for the fully lipped look as (to my knowledge at least) there is no compelling evidence to suggest otherwise.

The dark stripes on the face (especially the lower jaw) are inspired by the corresponding coloration qnd pattern seen in Chinese Crocodile Lizards (Shinisaurus crocodilurus). I didn't want to imitate it 1:1 but come up with something more unique though, so I hope that turned out well.

Description

Finally a new upload! I know this is coming about a month too late, but I hope y'all had a merry christmas and a happy new year. Anyways, regarding art the last few weeks or so haven't been the most productive for me, but since I want to add a new image to my gallery somewhat regularly (at least once a month) I put together this.

This portrait depicts Oxalaia quilombensis, a very fragmentary Brazilian spinosaurine theropod from the Cenomanian stage of the Late Cretaceous (95-ish million years ago) of Cajual Island in the North East of the country. The species name derives from the quilombolas people who inhabit the island, while the genus name refers to Oxalá, the Brazilian version of the African god Obatala (introduced to South America by escaped slaves who also founded the quilombo settlements).

First discovered in 1999 by paleontologists of the National Museum in Rio de Janeiro, Oxalaia remained unstudied for many years until being formally tackled by Aleander Kellner and collegues in 2011. As already noted, the fossil material that the description and erection of this taxon is based on is pretty fragmentary (so fragmentary in fact, that this reconstruction features all of what is known). The holotype is represented by the tip of the snout (fused premaxillary bones) and the small part of a left maxilla that was also attributed to this dinosaur despite being found isolated from the rest. Several spinosaur teeth as well as vertebrae (all labelled as Bahariyasaurus) found in the same region may also come from Oxalaia, although there is no way to say this for certain.

Although even with the known remains being far from complete, some unique traits could be identified that according to the authors justify the classificication as a new genus and species. Not all paleontologists agree with this.Following this alternative view the Oxalaia.specimens would fall under Spinosaurus (maybe under S. aegyptiacus or as ist own species S. quilombensis? The taxonomy of the African spinosaurines is also quite messy by the way) and the differences between those two could be explained as examples of individual variation. Due to the incomplete nature of Oxalaia this is a hard question to properly answer and unfortunately any chance of working with the original material may have been lost. In 2018 there was a big fire at the museum in Rio de Janeiro that many fossils housed in the building didn't survive. The bones of the enigmatic Oxalaia are possibly among them.

So in terms of overall appearence Oxalaia would have most likely pretty much resembled Spinosaurus, even if classified as a distinct dinosaur. Studies have recovered it as the closest known relative of the famous sailback from Africa. The presence of another slightly older spinosaurine in Brazil called Angaturama (which some incidentally view as a junior synonym of Irritator) suggests that there was a strong biogeographic connection between the continents of Western Gondwana as they were connected until the Late Lower Cretaceous. Even in the Early Upper Cretaceous, at the time when Oxalaia and Spinosaurus roamed, Northern Africa and South America (or at least Cajual Island) would have probably been linked by some sort of island chain or something similar.

The Alcântara Formation, the home of Oxalaia would been heavily vegetated and fairly humid, even though adjacent regions were probably much dryer. Contemporaries of the spinosaur include rebbachisaurids, titanosaurs, various theropods such as noasaurids, carcharodontosaurs, dromaeosaurids and even fellow spinosaurids, crocodile-relatives and lots of fish (featuring some big ones which would have been part of Oxalaia's diet among other creatures). This assemblage shares quite many resemblences to the ones uncovered in similarly aged rocks in North African countries.

In terms of integument I tried to make the snout appear somewhat hardened or "toughened" because this is a body part that would have been especially subjected to the environment through activities such as hunting, inter- and intraspecific combat or generally coming into contact with surrounding stuff. I also decided to add a considerable amount of extra oral tissue. I've noticed that there are different approaches for spinosaurs when it comes to this topic. Some reconstructions show them with exposed teeth (somewhat similar to crocodiles) while in others only the teeth in the front of the closed mouth are visible. However, I went for the fully lipped look as (to my knowledge at least) there is no compelling evidence to suggest otherwise.

The dark stripes on the face (especially the lower jaw) are inspired by the corresponding coloration qnd pattern seen in Chinese Crocodile Lizards (Shinisaurus crocodilurus). I didn't want to imitate it 1:1 but come up with something more unique though, so I hope that turned out well.