The paleo art of Gabriel Ugueto on YouTube

https://www.youtube.com/watch?v=BKRAzhMjQbo   39 minutes
The Weirdest Triassic Animals | Ft. Gabriel Ugueto | Paleoart Showcase Ep #2
‘People Are Fish’ = content creator

Apologies. The usual links are not hyperlinked this time. Nor are taxa italicized.

Excellent artist! Even so, some corrections follow:
@1:15 that’s Ugueto’s illustration of Scleromochlus – a bipedal basal crocodylomorph. So, no feathers, no fuzz. Not ‘the birth of dinosaurs’, but should be bipedal. It has the smallest hands vs longest legs out there. It’s awkwardly struggling to be quadrupedal in the illustration.

@1:26 not ‘all the turtles’. That appears to be Odontochelys, a basal softshell turtle. Hardshell turtles had a different ancestor in the horn-head Elginia.
@1:51 Meiolania should preceded Proganochelys, not follow. Note the horns on the head.

@1:56 Contra the claim that ‘nobody knows where they [turtles] fit in the reptile tree’ a cladogram that tests all competing taxa, ‘the large reptile tree’ (LRT) online, knows with that authority.

@2:03 Neither the the ‘old’ nor the ‘new’ family tree is correct. Theropods split from Bakker’s phytodinosauria = sauropodomorpha + ornithischia + basa phytodinosaurs in the LRT.

@2:45 Mirasaura was more or less correctly linked to Longisquama, but both were incorrectly linked to drepanosaurs. A closer connection is to the omitted taxon, Occuludentavis and these are all related to Cosesaurus and Sharovipteryx, transitional between tiny tanytropheids and pterosaurs, where the wings take over for the dorsal plumes as display signals. Unfortunately the authors of that study misidentified an elongate ilium as a femur, hence the extremely short hind limbs on Ugueto’s art.

@3:30 those plumes on Mirasaura are homologs to similar, but shorter structures on the backs of Iguana and Sphenodon. As Peters 2007 reported and the LRT shows, all are lepidosaurs.

@4:33 Longisquama should be bipedal with much longer hind limbs and a wire-like = pterosaur-like tail lacking caudofemoralis muscles. The forelimbs had an oversized folding digit 4, as in pterosaurs. The sternal complex and elongate, locked-down coracoid indicate flapping was a behavior, as in pterosaurs and birds. Sharov, an insect-specialist, mistook a tibia + femur for a displaced plume. In the background is an out-of-focus Sharovipteryx incorrectly shown gliding with sprawling hind limbs. This biped had enlarged uropatagia (a display signal) and a wire-like = pterosaur-like tail and pterosaur-like extradermal fibers.

@5:00 the skull of Mirasaura is shown and described as ‘bird-like’, as earlier reported for Oculudentavis. That paper was forced into retraction because others noted its lepidosaurian traits. Again, coming back to lepidosaurs.

@6:23 Scleromochlus again. There’s a good reason why ‘they look like dinosaurs’, because the sister group of herrerasaurids are basal bipedal crocodylomorphs (not often studied), and their last common ancestors were bipedal poposaurs in the LRT.

@6:32 Ugueto mistakenly labels Scleromochlus a lagerpetid. Lagerpeton is also a biped, but a sister to Tropidosuchus (in the LRT and elsewhere) nesting in the otherwise quadrupedal proterochampsid family, largely from South America.
@6:40 Ugueto mistakenly labels lagerpetids as ‘pterosauromorphs’. The tiny hands and the feet lacking pedal digit 5, among a long list of other traits, indicate otherwise. Unfortunately paleontologists involved with Scleromochlus have cherry-picked taxa to compare it to. The LRT compares all tested taxa with 2340 other taxa.

@6:43 a false image of pterosaur evolution (climbing up a tree, then gliding off a branch) is shown. This image ignores the literature and ignores the first ability to flap while running bipedally, as in early birds, prior to flying.

@6:52 this skeleton of Scleromochlus has tiny hands lacking a manual digit 4 longer than the medial three ‘free’ fingers. That’s the opposite of pterosaurs, Sharovipteryx, Cosesaurus and kin. The tail has deep chevrons, anchors for the caudofemoralis muscles – the opposite of pterosaurs, Sharovipteryx, Cosesaurus and kin, all of which substitute a prepubis. The foot lacks the tanystropheid-like elongate pedal digit 5 found in Sharovipteryx, etc. In fact, the foot of Scleromochlus lacks a pedal digit 5. This was all worked out 26 years ago, so it is surprising to see this hypothesis resurfacing. Cherry-picking citations, unfortunately, leads to this sort of forcing a round peg into a square hole.

@7:36 pycnofibers cannot be homologous with feathers on dinosaurs. This is revealed to be an example of convergence after analysis.

@8:00 Mecistotrachelus is a coelurosauravid nesting at the base of the Lepidosauria. Permian Tridentinosaurus is a last common ancestor in the LRT, so not related to archosauromorphs. While superficially similar to extant Draco, which does extend ribs, these earlier convergently gliding lepidosaurs extended elongate dermal bones arising from the tips of their ribs, sometimes reduced to the length of lateral vertebral processes. Google: ‘Mecistotrachelos, the Walking Stick “Rib” Glider’ for a skeleton, details, links and citations. Google: ‘Icarosaurus, Kuehneosaurus and the So-Called “Rib” Gliders’.

@9:04 Ugueto compares Mecistotrachelos to another taxon with a long neck, Tanystropheus. Never a good idea to make comparisons based on a single trait. Rather test all the traits against a wide gamut of competing taxa to determine the best = most parsimonious = fewest changes interrelationship.

@9:30 Shringasaurus is mistakenly labeled an archosauromorph. In the LRT this taxon nests with Azendohsaurus and Teraterpeton in the Rhynchocephalia, a lepidosaur clade.

@9:55 the skeleton includes an interclavicle (n), a trait common in lepidosaurs, lacking in archosauromorphs.

@10:55 Ugueto introduces proterochampsids as ‘rather cursorial’. This culminates in Tropidosuchus and Lagerpeton (see above).

@12:10 Parasuchians = phytosaurs are introduced. In the LRT these are related to choristoderes and proterochampsids, all of which evolved from proterosuchids. So the LRT tells us exactly what they were. The traditional clade, ‘Pseudosuchia’ is not recognized = not monophyletic by the LRT

@15:19 Tanytrachelos is correctly identified as a small tanystropheid, but that comes as a surprise to the narrator, who only knew them as large taxa.

@15:50 Shuvosaurus is introduced as a ‘pseudosuchian’. It is a poposaur in the LRT, close to Silesaurus and Lotosaurus, as recognized by Ugueto in the video.

@17:07 a cladogram of the Poposauroidea is presented that includes many, but not all members recovered in the LRT, and a few taxa that nest outside the LRT poposaurs.

@18:44 Ugueto labels the Rauisuchia an informal group. In the LRT it is a clade.

@19:50 Ugueto includes Terrestrisuchus in the group. In the LRT that taxon is a basal crocodylomorph.

@21:18 Cartorhynchus is introduced as a basal ichthyosaur. In the LRT that taxon is a basal sauropterygian = pachypleurosaur close to Qianxisaurus, not far from related placodonts.

@22:20 Early Triassic Shonisaurus is shown to scale with a flock of pterosaurs for scale. This is too soon for even basal pterosaurs, which evolved in the Late Triassic.

@27:50 Vancleavea is labeled as ‘related to proterochampsids… but looks completely different’. In the LRT Vancleavea is related to Helveticosaurus, a thalattosaur, which it closely resembles.

@29:24 Daemonosaurus is labeled an early theropod. In the LRT it is a basal ornithischian close to Jeholosaurus, basal to Heterodontosaurus and derived from Chilesaurus.
Again, wonderful artwork. Taxon exclusion is the cause for some of the phylogenetic confusion listed above.

Source: https://pterosaurheresies.wordpress.com/2026/04/25/the-paleo-art-of-gabriel-ungueto-on-youtube/