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Description
Desmatosuchus spurensis

The Triassic Period was the era of evolutionary oddities and the rise of the archosaurs.
Along with the first dinosaurs appearing in the Late Triassic, there were many other creatures that existed long before the iconic "terrible lizards" truly dominated the land.
Among them were the pseudosuchians, this group of archosaurs would eventually give rise to modern crocodilians. However, during the Triassic, they saw an explosion in diversity filling a variety of niches. Among the most unique were the aetosaurs.
Aetosaurs were unique among pseudosuchians. They were a group of armored pseudosuchians with armor covering their bodies, with erect pillar-limbs similar to their cousins, the rauisuchians. However, unlike the rauisuchians and modern crocodilians, these creatures were exclusively herbivorous. Equipped with leaf-shaped teeth, they were designed to slice through vegetation in the various Triassic ecosystems be it floodplains or arid environments across the supercontinent of Pangea. They generally filled the niche of large herbivorous creatures along with dicynodonts and early sauropodomorph dinosaurs.
One subfamily of aetosaurs, the Desmatosuchinae were larger than their cousins and more heavily armored. The largest and most iconic was the type genus of the subfamily was Desmatosuchus itself.

History of Discovery:

In 1887, during the Bone Wars, Edward Drinker Cope described a creature from fossils recovered from the Dockum Group in Texas known as "Episcoposaurus haplocerus". The fossils of this creature consisted of a sacrum, ribs, two relatively complete caudal vertebra, a right scapula, and more than 30 armor plates. The genus name derives from the Greek, "episcopus" meaning "bishop", a reference to the caudal scutes on resembling a bishop's mitre (headgear that they wear). The species name, "haplocerus" derives from the Greek "Haplo" meaning "simple" and "cerus" meaning "horn", referencing the horn-like armor of the plates. The fossils were stowed in the academy of natural sciences in Philadelphia following their description.
Then, 30 years later in 1917, Professor E.C. Case of the University of Michigan was overseeing a dig site in the Dockum Group when his team discovered a partially articulated specimen of a new pseudosuchian. He called it Desmatosuchus spurensis. The genus name means derives from "desmos" meaning "link" and "soûkhos" meaning crocodile. And the species name derives from the spur-like armor on the tail. It would not be until March 2007 when Dr. William G. Parker, re-evaluated Cope's holotype and since they were found in such close proximity to each other, the two names were considered synonyms. However, a year later, it was found that Episcoposaurus haplocerus' holotype was indeterminate at the species level, and thus considered a "nomen dubium" (dubious name), and D.spurensis is considered the type species.

Fossils:

Fossils of this animal have been found exclusively in North America. Hailing from the Dockum Group in Texas and the Chinle Formation in Arizona and New Mexico. Desmatosuchus lived during the Late Triassic from 228-210,000,000 years ago.
Its habitat was largely a tropical floodplain environment. Desmatosuchus would have browsed off plants like ferns, cycad, and other low-lying vegetation. With no Sauropodomorphs in the region, it along with stem-mammals like the large dicynodont Placerias were the main herbivores in this region of the supercontinent.

Description:

Desmatosuchus was the largest of all aetosaurs. With the largest individuals reaching up to 16ft long and weighing in at half a ton, it was a massive herbivore for its time. The skull was small, just over a foot long. At the end of the snout, there was a distinctive shovel-shaped structure. Some have suggested the shovel-like structure would have been useful in digging through the mud along the riverbanks of the Chinle and Dockum formations to get at softer vegetation and roots. The shovel structure was likely covered in a keratinous structure that was designed to help it clip vegetation. In fact, its jaw is reminiscent of some ornithischian dinosaurs. The way the jaw articulated created a sort of "nut-cracker" effect where the bottom teeth remained parallel to the top jaw, maintaining an even bite force.
Unique to this genus were the distinctive shoulder spikes. The spikes were actually extensions of the acromion processes of their scapulae. Like all aetosaurs, they were heavily armored reptiles. The carapace had 2 rows of median scutes and two more rows of lateral scutes. The lateral scutes had spine-like processes which pointed out laterally. The lateral spike rows show variation from individual to individual, with some shorter and some longer than others. Some paleontologists proposed the spines are indicative of sexual dimorphism.
The armor and spikes were almost certainly for deterring predation/protection, with a possible secondary function for display. In Triassic North America, they needed this armor. Massive predatory pseudosuchians and some of the first theropod dinosaurs stalked the landscape it lived in. Scutes of Desmatosuchus have been found in close proximity to the large rauisuchian Postosuchus. Indicating a possible predator-prey relationship.

Habitat and Behavior:

Fossils described from the Chinle Formation and Dockum Group consist of several individuals found together. Some have suggested this was indicative of herding behavior, including one fossil site with 5 adults and one juvenile skeleton found near St. Johns Arizona. However, it should be noted that other creatures like Placerias and more notably, the dinosaur Coelophysis have been found in various localities across the Chinle Formation and are found in huge numbers. It could be possible that there was a flash flood and various individuals got washed together. Without any way to observe any of the Chinle or Dockum fauna, we will never know the true extent of their behavior.

Extinction:

Desmatosuchus vanished 210,000,000 years ago, however, its cousin, Paratypothorax from the same region (and also from Greenland) would persist till around 199,000,000 years ago, and then the aetosaurs would die off from another extinction event.
Among the survivors would be the Dinosaurs, Pterosaurs, and the ancestors of modern Crocodilians. While these unique Pseudosuchians would vanish, their niche would be filled throughout the Mesozoic by their distant cousins, the thyreophoran dinosaurs, the Stegosaurs, and Ankylosaurs.
___________________________________________________________________________________________
Another icon of the Triassic. I decided to do it after watching DrPolaris 's video on Aetosaurs as well as Royal Tyrell Museum's Lecture
Aetosaurs: Herbivorous Crocodile Relatives - YouTube
Before Ankylosaurs, There Were Aetosaurs - YouTube

FYI: Most of the info I got for this profile was here:
ttu-ir.tdl.org/bitstream/handl…
^^^A master's thesis published in 1985. Pretty decent info, (aside from the outdated thecodont moniker).

The model was made by LazardiK and non-modified. The Postosuchus was made by DinosaurManZT2 and was modified by me (shown earlier as well). I decided to base this profile's poses off of Houston's Museum's mounts of Postosuchus and Desmatosuchus.

Will this be in Past Meets Present? Yes, it will, I've stated Chinle will be a target for the second season and have got some good scenes in mind.

Model and skin by LazardiK
Desmatosuchus (Lazardi & Tyranachu) | ZT2 Download Library Wiki | Fandom

For Past Meets Present:
Past Meets Present (Pt4 is Up) - Page 2 - The ZT2 Round Table

Description
Desmatosuchus spurensis

The Triassic Period was the era of evolutionary oddities and the rise of the archosaurs.
Along with the first dinosaurs appearing in the Late Triassic, there were many other creatures that existed long before the iconic "terrible lizards" truly dominated the land.
Among them were the pseudosuchians, this group of archosaurs would eventually give rise to modern crocodilians. However, during the Triassic, they saw an explosion in diversity filling a variety of niches. Among the most unique were the aetosaurs.
Aetosaurs were unique among pseudosuchians. They were a group of armored pseudosuchians with armor covering their bodies, with erect pillar-limbs similar to their cousins, the rauisuchians. However, unlike the rauisuchians and modern crocodilians, these creatures were exclusively herbivorous. Equipped with leaf-shaped teeth, they were designed to slice through vegetation in the various Triassic ecosystems be it floodplains or arid environments across the supercontinent of Pangea. They generally filled the niche of large herbivorous creatures along with dicynodonts and early sauropodomorph dinosaurs.
One subfamily of aetosaurs, the Desmatosuchinae were larger than their cousins and more heavily armored. The largest and most iconic was the type genus of the subfamily was Desmatosuchus itself.

History of Discovery:

In 1887, during the Bone Wars, Edward Drinker Cope described a creature from fossils recovered from the Dockum Group in Texas known as "Episcoposaurus haplocerus". The fossils of this creature consisted of a sacrum, ribs, two relatively complete caudal vertebra, a right scapula, and more than 30 armor plates. The genus name derives from the Greek, "episcopus" meaning "bishop", a reference to the caudal scutes on resembling a bishop's mitre (headgear that they wear). The species name, "haplocerus" derives from the Greek "Haplo" meaning "simple" and "cerus" meaning "horn", referencing the horn-like armor of the plates. The fossils were stowed in the academy of natural sciences in Philadelphia following their description.
Then, 30 years later in 1917, Professor E.C. Case of the University of Michigan was overseeing a dig site in the Dockum Group when his team discovered a partially articulated specimen of a new pseudosuchian. He called it Desmatosuchus spurensis. The genus name means derives from "desmos" meaning "link" and "soûkhos" meaning crocodile. And the species name derives from the spur-like armor on the tail. It would not be until March 2007 when Dr. William G. Parker, re-evaluated Cope's holotype and since they were found in such close proximity to each other, the two names were considered synonyms. However, a year later, it was found that Episcoposaurus haplocerus' holotype was indeterminate at the species level, and thus considered a "nomen dubium" (dubious name), and D.spurensis is considered the type species.

Fossils:

Fossils of this animal have been found exclusively in North America. Hailing from the Dockum Group in Texas and the Chinle Formation in Arizona and New Mexico. Desmatosuchus lived during the Late Triassic from 228-210,000,000 years ago.
Its habitat was largely a tropical floodplain environment. Desmatosuchus would have browsed off plants like ferns, cycad, and other low-lying vegetation. With no Sauropodomorphs in the region, it along with stem-mammals like the large dicynodont Placerias were the main herbivores in this region of the supercontinent.

Description:

Desmatosuchus was the largest of all aetosaurs. With the largest individuals reaching up to 16ft long and weighing in at half a ton, it was a massive herbivore for its time. The skull was small, just over a foot long. At the end of the snout, there was a distinctive shovel-shaped structure. Some have suggested the shovel-like structure would have been useful in digging through the mud along the riverbanks of the Chinle and Dockum formations to get at softer vegetation and roots. The shovel structure was likely covered in a keratinous structure that was designed to help it clip vegetation. In fact, its jaw is reminiscent of some ornithischian dinosaurs. The way the jaw articulated created a sort of "nut-cracker" effect where the bottom teeth remained parallel to the top jaw, maintaining an even bite force.
Unique to this genus were the distinctive shoulder spikes. The spikes were actually extensions of the acromion processes of their scapulae. Like all aetosaurs, they were heavily armored reptiles. The carapace had 2 rows of median scutes and two more rows of lateral scutes. The lateral scutes had spine-like processes which pointed out laterally. The lateral spike rows show variation from individual to individual, with some shorter and some longer than others. Some paleontologists proposed the spines are indicative of sexual dimorphism.
The armor and spikes were almost certainly for deterring predation/protection, with a possible secondary function for display. In Triassic North America, they needed this armor. Massive predatory pseudosuchians and some of the first theropod dinosaurs stalked the landscape it lived in. Scutes of Desmatosuchus have been found in close proximity to the large rauisuchian Postosuchus. Indicating a possible predator-prey relationship.

Habitat and Behavior:

Fossils described from the Chinle Formation and Dockum Group consist of several individuals found together. Some have suggested this was indicative of herding behavior, including one fossil site with 5 adults and one juvenile skeleton found near St. Johns Arizona. However, it should be noted that other creatures like Placerias and more notably, the dinosaur Coelophysis have been found in various localities across the Chinle Formation and are found in huge numbers. It could be possible that there was a flash flood and various individuals got washed together. Without any way to observe any of the Chinle or Dockum fauna, we will never know the true extent of their behavior.

Extinction:

Desmatosuchus vanished 210,000,000 years ago, however, its cousin, Paratypothorax from the same region (and also from Greenland) would persist till around 199,000,000 years ago, and then the aetosaurs would die off from another extinction event.
Among the survivors would be the Dinosaurs, Pterosaurs, and the ancestors of modern Crocodilians. While these unique Pseudosuchians would vanish, their niche would be filled throughout the Mesozoic by their distant cousins, the thyreophoran dinosaurs, the Stegosaurs, and Ankylosaurs.
___________________________________________________________________________________________
Another icon of the Triassic. I decided to do it after watching DrPolaris 's video on Aetosaurs as well as Royal Tyrell Museum's Lecture
Aetosaurs: Herbivorous Crocodile Relatives - YouTube
Before Ankylosaurs, There Were Aetosaurs - YouTube

FYI: Most of the info I got for this profile was here:
ttu-ir.tdl.org/bitstream/handl…
^^^A master's thesis published in 1985. Pretty decent info, (aside from the outdated thecodont moniker).

The model was made by LazardiK and non-modified. The Postosuchus was made by DinosaurManZT2 and was modified by me (shown earlier as well). I decided to base this profile's poses off of Houston's Museum's mounts of Postosuchus and Desmatosuchus.

Will this be in Past Meets Present? Yes, it will, I've stated Chinle will be a target for the second season and have got some good scenes in mind.

Model and skin by LazardiK
Desmatosuchus (Lazardi & Tyranachu) | ZT2 Download Library Wiki | Fandom

For Past Meets Present:
Past Meets Present (Pt4 is Up) - Page 2 - The ZT2 Round Table