Read the Beforeitsnews.com story here. Advertise at Before It's News here.

By David Peters
Contributor profile | More stories

Story Views
Now:
Last hour:
Last 24 hours:
Total:

Herbivorous Ectoganus now nests tentatively with carnivorous Sinonyx in the LRT

Wednesday, August 12, 2026 23:01

% of readers think this story is Fact. Add your two cents.

This hypothetical interrelationship
took a long time to recognize – if it is even valid. The large reptile tree (LRT, 2340 taxa) now nests herbivorous Ectoganus and its stylondontid descendants with lthe larger, predatory Sinonyx (Fig 1) as its phylogenetic ancestor.

The narrow palate, no wider than the molars that line the edges, together with that extremely tall, narrow cranial crest (anchor large jaw muscles) found in both taxa are only a few of the many traits that unites these two in the LRT.

Figure 1. A little phylogenetic miniaturization and a change of diet drove flat-toothed Ectoganus and its descendants apart from the larger, sharp-toothed Synonyx in the LRT. Little Ptolemaia is also shown here to scale.

Traditionally Sinonyx
is a wolf-like mesonychid from the late Paleocene of China (56 mya). Note the claws = unguals are not well developed.

Figure 2. Sinonyx is close to Mesonyx, but closer to Arctocyon in the LRT. Note the unguals = claws are not so well-dvelooped and have a broader hoof-like appearance. Hoofed mammals are generally herbivores, but this one does not give that appearance in the skull.

Traditionally Ectoganus
is a taeniodont within the Stylinodontinae. It lived in North America from the Late Paleocene to Early Eocene.

Figure 3. Psittacotherium in various views. This taxon nests with Ectoganus as a basal stylinodont in the LRT. It provides post-cranial data. Note the hyper-enlarged claws = unguals here along with the flattened post-canine teeth. Even the canine has lost its tip. Note the resemblance of the retroarticular process here to that in Sinonyx in figure 1.

Earlier I made about all the mistakes one can make
trying to figure out the stylinodontids. The present hypothesis could use a nice transitional taxon between Sinonyx and Ectoganus. Lacking that, at present, this is what the LRT came up with given the present scoring = the human factor.

Figure 4. Three distinct taxa all considered Stylinodon (genus) are below Ectoganus here. Groeberia nests with Stylinodon 3 (black background) and I wonder if Groeberia is a juvenile Stylinodon 3 or is it just small?

That narrow palate common to Sinonyx and Ectoganus
is not a character that is currently scored in the LRT. On that note, please note the palate in Psittacotherium (Fig 3) is not narrow – but the maxilla also has a deep gulch = raised roof that is not found in other mammals. So I wonder if one side of the skull was rotated too much during the taking of the photograph, which widened the palate relative to the tooth rows.

Welcome to my nightmare, as I recognize and try to deal with apparent exceptions in incomplete fossil data.

On a more positive note, the mammal subset of the LRT has never been so well resolved with sister taxa greatly resembling one another in a graduation modeling evolutionary processes.

References
Marsh OC 1874. Notice of new Tertiary mammals 3. American Journal of Science. (3) 7i: 531-534.
Schoch RM 1981. Revision of the middle Paleocene (Torrejonian) taeniodont (Mammalia)
Psittachotherium Cope, 1882, p. 177-85. In Lucas SG, Rigby JK, Jr., and Kues BS [eds.]. Advances in San Juan Basin paleontology. University of New Mexico Press, Albuquerque.
Zhou X, Zhai R, Gingerich PD and Chen L 1995. Skull of a new mesonychid (Mammalia, Mesonychia) from the Late Paleocene of China. Journal of Vertebrate Paleontology 15(2):387-400.

wiki/Ectoganus
wiki/Stylinodon
wiki/Sinonyx

Source: https://pterosaurheresies.wordpress.com/2026/08/13/herbivorous-ectoganus-now-nests-tentatively-with-carnivorous-sinonyx-in-the-lrt/

Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world. Anyone can join. Anyone can contribute. Anyone can become informed about their world. "United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

LION'S MANE PRODUCT

Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules

Mushrooms are having a moment. One fabulous fungus in particular, lion’s mane, may help improve memory, depression and anxiety symptoms. They are also an excellent source of nutrients that show promise as a therapy for dementia, and other neurodegenerative diseases. If you’re living with anxiety or depression, you may be curious about all the therapy options out there — including the natural ones.Our Lion’s Mane WHOLE MIND Nootropic Blend has been formulated to utilize the potency of Lion’s mane but also include the benefits of four other Highly Beneficial Mushrooms. Synergistically, they work together to Build your health through improving cognitive function and immunity regardless of your age. Our Nootropic not only improves your Cognitive Function and Activates your Immune System, but it benefits growth of Essential Gut Flora, further enhancing your Vitality.

Our Formula includes: Lion’s Mane Mushrooms which Increase Brain Power through nerve growth, lessen anxiety, reduce depression, and improve concentration. Its an excellent adaptogen, promotes sleep and improves immunity. Shiitake Mushrooms which Fight cancer cells and infectious disease, boost the immune system, promotes brain function, and serves as a source of B vitamins. Maitake Mushrooms which regulate blood sugar levels of diabetics, reduce hypertension and boosts the immune system. Reishi Mushrooms which Fight inflammation, liver disease, fatigue, tumor growth and cancer. They Improve skin disorders and soothes digestive problems, stomach ulcers and leaky gut syndrome. Chaga Mushrooms which have anti-aging effects, boost immune function, improve stamina and athletic performance, even act as a natural aphrodisiac, fighting diabetes and improving liver function. Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules Today. Be 100% Satisfied or Receive a Full Money Back Guarantee. Order Yours Today by Following This Link.

Comments

Visits:	1,828,475,665
Stories:	8,686,453