#eutriconodont

[harpagornis]

Liaoconodon chasing after fish while a Liaoningosaurus watches. By @theenantiornithebandwagon.

[si-nequal-is]

Sleepy Repenomamus and awake Mei

[dragonthunders01]

So here is my V2 of my old picture of the species Ichthyoconodon jaworowskorum, an unsual eutriconodont found in the sea deposits of the lower cretaceous Morroco, being its only known remains formed by two lower jaw Molars, MNHN SA 46 (a) and SA 78 (b). Is really little of what it is known about this as with two teeth there isn't much what can be inferred, just probably that they were some inhabitants of the coastal region of Northwest coast of africa... and that's pretty much it, nothing else can be taken from 2 isolated teeth. Honestly is a shame that this and many relatives of these are just little know from few complete specimens, and just mostly being jaws and teeth what it is found.

[harpagornis]

Celebrating bat appreciation week with the rather non-bat volaticothere commissions of @paleoart, mammals that flew 100 million years before bats did!

[harpagornis]

Flexing my genius before going to bed. Remember,Ichthyoconodon and other volaticotheres could fly: https://mullerornis.medium.com/ichthyoconodon-98c42f9667be

[harpagornis]

Flying volaticothere goodies by alphynix, Argentoconodon and Triconolestes respectively. Volaticotheres flew, and the fact that this makes pissants angry only drives me forward.

[harpagornis]

Indotriconodon flies,baby!

By omegafreelancer

So learning that Indotriconodon magnus – an already impressive animal in being a large sized Mesozoic mammal and an unambiguous eutriconodont from the Maastrichtian – is also a volaticothere I naturally had to commission it in its likely volant form.

Volaticotheria phylogenetic tree by Bajpai et al 2024

Its debuting study also recover Sangarotherium and Eotriconodon as volaticotheres. The former in particular is the only mammal in an Arctic environment dominated by other synapsids (Averianov et al 2020), so it clearly must have been able to fly and migrate when other crown mammals couldn’t.

Things just keep looking up for volaticothere flight, which I already extensively argued for with the marine deposition and lack of dental wear of Ichthyoconodon, the early cosmopolitan distribution of the group, the fact that Volaticotherium‘s hand is largely missing and the fact that gliding mammals are primarily herbivorous (Luo 2017).

Naturally, I also used this image to forward my speculative volaticotheres over at Lemuria.

What a wonderous day.

References

Bajpai, Sunil; Rautela, Abhay; Yadav, Ravi; Wilson Mantilla, Gregory P. (2024-02-29). “The first eutriconodontan mammal from the Cretaceous (Maastrichtian) of India”. Journal of Vertebrate Paleontology. doi:10.1080/02724634.2024.2312234. ISSN 0272-4634.

Averianov, Alexander; Martin, Thomas; Lopatin, Alexey; Skutschas, Pavel; Schellhorn, Rico; Kolosov, Petr; Vitenko, Dmitry (2018-07-25). “A high-latitude fauna of mid-Mesozoic mammals from Yakutia, Russia”. PLOS ONE. 13 (7): e0199983. Bibcode:2018PLoSO..1399983A. doi:10.1371/journal.pone.0199983. ISSN 1932-6203. PMC 6059412. PMID 30044817.

Luo ZX, Meng QJ, Grossnickle DM, Liu D, Neander AI, Zhang YG, Ji Q (August 2017). “New evidence for mammaliaform ear evolution and feeding adaptation in a Jurassic ecosystem”. Nature. 548 (7667): 326–329. doi:10.1038/nature23483. PMID 28792934. S2CID 4463476.

[harpagornis]

Speculative Evolution: Herbivorous Eutriconodont

In some other timeline, a lineage of eutriconodonts (specifically, within Triconodontidae) survive the KT event in Asia. Though succeeding as carnivores in the absence of carnivorans, one genus, Cynoailurus, begins specializing as bamboo specialists. Free green protein, y'all.

Now the triconodont type tooth has evolved into the numerous conditions seen in other mammals, from the turbercules of multituberculates to the talonid of therians to whatever toothed monotremes were doing. The triconodont type dentition was adapted for shearing meat, after all, so it had to change.

Cynoailurus took the path of least resistance and simply dulled and strengthened its cusps. No fancy alterations, just blunt points. Its adapted to pierce through bamboo after all, so no there was no need of fancy adaptations beyond perforation and crushing. The animal doesn't undergo extensive oral processing, so it kept just a slightly modified triconodont dentition.

To help grab bamboo it simply developed an opposite thumb. Several species ranging from the size of a cat to a panda bear exist, all solitary animals taking advantage of multiple species of bamboo. They give birth to altricial young (just like real pandas!) and reach sexual maturity late, as late as ten years in some species.

Most are endangered, but managed to snuggle their way into the hearts of the sophonts of their timeline (intelligent symmetrodonts) because that's how life finds a way.