| Flowerpot Formation | |
|---|---|
| Stratigraphic range: Early Permian, Cisuralian | |
| Type | Formation |
| Unit of | Pease River Group |
| Underlies | Blaine Formation |
| Overlies | Duncan Formation |
| Lithology | |
| Primary | Shale |
| Other | Gypsum, Conglomerate |
| Location | |
| Region | Texas, Oklahoma |
| Country |  United States |
Flowerpot Formation (also referred to as the Flower Pot Formation) is a geologic formation in Texas and Oklahoma preserving fossils dated to the Early Permian .
The Flowerpot formation is very similar in geology to and was once thought to overlie the San Angelo formation, sometimes only being able to be differentiated by what layer underlie the unit in the area of study, both being mostly made up of red shales. Though unlike San Angelo, the depositional environment of the terrestrial shales of the Flowerpot formation seemed to be immediately adjacent along with the formation of deltas and floodplains being present. Due to this, stream deposits from the formation can directly be traces to the nearby basin. The formation lacks plant fossils, however there are records of carbonaceous streaks. [1]
| Genus | Species | Notes | Image |
|---|---|---|---|
| Palaeoniscidae? [1] | There is not much fish material preserved in the formation it is unknown if this is due to the preservation bias or the fact that not many fish lived in the area. |
| Genus | Species | Notes | Image |
|---|---|---|---|
| Cymatorhiza [2] | C. kittsi | A large microsaur known from a part of the mandible with tooth rooting similar to what is seen in other genera such as Euryodus . |
| Genus | Species | Notes | Image |
|---|---|---|---|
| Kahneria [1] | K. seltina | A large captorhinid common in the Flower Pot formation, the animal's dentition contained a diastema at the pterygoid. It was overall similar to other captorhinids such as Captorhinus. | |
| Rothianiscus [1] [3] | R. multidonta | A large captorhinid originally described as the genus Rothia, it had a skull length of around 26 cm. Based on the dentition, it would have been either herbivorous or omnivorous. |
| Genus | Species | Notes | Image |
|---|---|---|---|
| Angelosaurus [1] [2] | A. dolani | A caseid that lacks the development of the large proximal end of the tibia seen in other members of the family. A. romeri has shorter and wider crowns than what is seen in the other two species. | |
| A. greeni | |||
| A. romeri | |||
| Caseopsis [1] | C. agilis | A medium-sized caseid with a light build and long limbs, though the articular surfaces on the limb bones are small for the size of the animal. | |
| C. cf. agilis | A caseid very similar to C. agilis though due to poor preservation it can't be confidentially attributed to the species. It also has a slightly more robust tibia than what is seen in other specimens of C. agilis. | ||
| Cotylorhynchus [2] | C. bransoni | A large caseid though the smallest species within the genus. | |
| Steppesaurus [1] | S. gurleyi | A potential sphenacodontid that was originally though to be from the San Angelo formation before some geological revisions. The animal shows a large reduction in its dentition on the maxilla and premaxilla along with a slightly longer face than what is seen in Dimetrodon . |  |
| Genus | Species | Notes | Image |
|---|---|---|---|
| Sphenophyllum [2] | S. gilmorei |
Sphenacodontidae is an extinct family of sphenacodontoid synapsids. Small to large, advanced, carnivorous, Late Pennsylvanian to middle Permian "pelycosaurs". The most recent one, Dimetrodon angelensis, is from the latest Kungurian or, more likely, early Roadian San Angelo Formation. However, given the notorious incompleteness of the fossil record, a recent study concluded that the Sphenacodontidae may have become extinct as recently as the early Capitanian. Primitive forms were generally small, but during the later part of the early Permian these animals grew progressively larger, to become the top predators of terrestrial environments. Sphenacodontid fossils are so far known only from North America and Europe.
Caseoides is an extinct genus of large caseid synapsids that lived in the Kungurian Age. It was about 3 metres (9.8 ft) long, and like many other caseids, it was herbivorous and aquatic. It weighed between 150 and 200 kilograms. Its fossils were found in San Angelo Formation, Texas. Caseoides was very similar to Casea, but was slightly larger in size. Caseoides was a heavily built creature, as are most of the Caseids. In the development of its proportionally thick, stout limbs it represents the culmination of the Casea lineage. Its relatives became smaller during the Roadian Age. Only poorly preserved postcranial material is known including limbs.
Cotylorhynchus is an extinct genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) and possibly the early Middle Permian (Roadian) in what is now Texas and Oklahoma. The large number of specimens found make it the best-known caseid. Like all large herbivorous caseids, Cotylorhynchus had a short snout sloping forward and very large external nares. The head was very small compared to the size of the body. The latter was massive, barrel-shaped, and ended with a long tail. The limbs were short and robust. The hands and feet had short, broad fingers with powerful claws. The barrel-shaped body must have housed large intestines, suggesting that the animal had to feed on a large quantity of plants of low nutritional value. Caseids are generally considered to be terrestrial, though a semi-aquatic lifestyle has been proposed by some authors. The genus Cotylorhynchus is represented by three species, the largest of which could reach more than 6 m in length. However, a study published in 2022 suggests that the genus may be paraphyletic, with two of the three species possibly belonging to separate genera.
Angelosaurus is an extinct genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) and early Middle Permian (Roadian) in what is now Texas and Oklahoma. Like other herbivorous caseids, it had a small head, large barrel-shaped body, long tail, and massive limbs. Angelosaurus differs from other caseids by the extreme massiveness of its bones, particularly those of the limbs, which show a strong development of ridges, processes, and rugosities for the attachment of muscles and tendons. Relative to its body size, the limbs of Angelosaurus were shorter and wider than those of other caseids. The ungual phalanges looked more like hooves than claws. The few known cranial elements show that the skull was short and more robust than that of the other representatives of the group. Angelosaurus is also distinguished by its bulbous teeth with shorter and wider crowns than those of other caseids. Their morphology and the high rate of wear they exhibit suggests a diet quite different from that of other large herbivorous caseids, and must have been based on particularly tough plants. A study published in 2022 suggests that the genus may be paraphyletic, with Angelosaurus possibly only represented by its type species A. dolani.
Steppesaurus is an extinct genus of basal Eupelycosauria belonging to the Sphenacodontidae, related to Dimetrodon and Sphenacodon, from the Late Permian San Angelo Formation of Texas.
Trematopidae is a family of dissorophoid temnospondyls spanning the late Carboniferous to the early Permian. Together with Dissorophidae, the family forms Olsoniformes, a clade comprising the medium-large terrestrial dissorophoids. Trematopids are known from numerous localities in North America, primarily in New Mexico, Oklahoma, and Texas, and from the Bromacker quarry in Germany.
Dimacrodon is an extinct genus of non-mammalian synapsid from the latest Early Permian San Angelo Formation of Texas. It is distinguished by toothless, possibly beaked jaw tips, large lower canines and a thin bony crest on top of its head. Previously thought to be an anomodont therapsid related to dicynodonts, it was later found to lack any diagnostic features of anomodonts or even therapsids and instead appears to be a 'pelycosaur'-grade synapsid of uncertain classification.
Eosyodon is a dubious genus of extinct non-mammalian synapsids from the Permian of Texas. Its type and only species is Eosyodon hudsoni. Though it was originally interpreted as an early therapsid, it is probably a member of Sphenacodontidae, the family of synapsids that includes Dimetrodon.
Knoxosaurus is an extinct genus of non-mammalian synapsids containing the species Knoxosaurus niteckii that existed approximately 279.5 to 268 million years ago. It was named by American paleontologist Everett C. Olson in 1962 on the basis of fragmentary fossils from Middle Permian-age deposits in the San Angelo Formation of Texas in the United States. Olson placed Knoxosaurus in a new infraorder called Eotheriodontia, which he considered a transitional group between the more reptile-like "pelycosaurs" and the more mammal-like therapsids. Knoxosaurus and Olson's other eotheriodonts were later considered to be undiagnostic remains of basal synapsids, no more closely related to therapsids than are other pelycosaur-grade synapsids.
Mastersonia is an extinct genus of non-mammalian therapsids from the Lower Permian of San Angelo Formation, Texas. It is only known from a few, very large vertebrae.
Everett Claire Olson was an American zoologist, paleontologist, and geologist noted for his seminal research of origin and evolution of vertebrate animals. Through his research studying terrestrial vertebrate fossils he identified intervals of extinction in the Permian and Triassic. He developed the concept of chronofauna, which he defined as "a geographically restricted, natural assemblage of interacting animal populations that has maintained its basic structure over a geologically significant period of time". He also proposed stratigraphic correlations between North American and Russian vertebrate-bearing strata for which additional support was found much later. The drop in terrestrial vertebrate diversity he proposed in at the end of the Kungurian stage of the Permian period that occurred 270 million years ago now carries his name - Olson's Extinction. Alternatively, some scientists think that the change was gradual but that it looks abrupt because of a gap in the fossil record, called "Olson's Gap". Some of his other notable research also included the taxa Slaugenhopia, Trimerorhachis, and Waggoneria.
The Red Beds of Texas and Oklahoma are a group of Early Permian-age geologic strata in the southwestern United States cropping out in north-central Texas and south-central Oklahoma. They comprise several stratigraphic groups, including the Clear Fork Group, the Wichita Group, and the Pease River Group. The Red Beds were first explored by American paleontologist Edward Drinker Cope starting in 1877. Fossil remains of many Permian tetrapods have been found in the Red Beds, including those of Dimetrodon, Edaphosaurus, Seymouria, Platyhystrix, and Eryops. A recurring feature in many of these animals is the sail structure on their backs.
Paleontology in Oklahoma refers to paleontological research occurring within or conducted by people from the U.S. state of Oklahoma. Oklahoma has a rich fossil record spanning all three eras of the Phanerozoic Eon. Oklahoma is the best source of Pennsylvanian fossils in the United States due to having an exceptionally complete geologic record of the epoch. From the Cambrian to the Devonian, all of Oklahoma was covered by a sea that would come to be home to creatures like brachiopods, bryozoans, graptolites and trilobites. During the Carboniferous, an expanse of coastal deltaic swamps formed in areas of the state where early tetrapods would leave behind footprints that would later fossilize. The sea withdrew altogether during the Permian period. Oklahoma was home a variety of insects as well as early amphibians and reptiles. Oklahoma stayed dry for most of the Mesozoic. During the Late Triassic, carnivorous dinosaurs left behind footprints that would later fossilize. During the Cretaceous, however, the state was mostly covered by the Western Interior Seaway, which was home to huge ammonites and other marine invertebrates. During the Cenozoic, Oklahoma became home to creatures like bison, camels, creodonts, and horses. During the Ice Age, the state was home to mammoths and mastodons. Local Native Americans are known to have used fossils for medicinal purposes. The Jurassic dinosaur Saurophaganax maximus is the Oklahoma state fossil.
Gorgodon is an extinct genus of basal synapsids. The genus is monotypic, known only from the type species Gorgodon minutus from the Early Permian of the southwestern United States. The only known remains of Gorgodon are two fossils consisting of fragments of the skull. Gorgodon was described and named by paleontologist Everett C. Olson in 1962 from the San Angelo Formation in Knox County, Texas. Based on what is known of Gorgodon—the squamosal, quadrate, and pterygoid bones of the back of the skull, the maxilla and premaxilla bones that make up the front of the skull, and several teeth—Gorgodon had a relatively large temporal fenestra and a pair large, conical caniniform teeth at the front of the jaw. Other distinguishing features of Gorgodon include the fused connection between the quadrate and squamosal bones and a long transverse process of the pterygoid.
The Chickasha Formation, which is part of the El Reno Group, is a geologic formation in Oklahoma. It preserves fossils dating back to the Roadian stage of the Middle Permian. These include, among others, the dissorophoid temnospondyl Nooxobeia gracilis, the lepospondyl Diplocaulus parvus, and the captorhinid Rothianiscus robusta, initially called Rothia robusta by Everett C. Olson. Many of these fossils were indicated to have come from the Flowerpot Shale, but these actually come from the Chickasha Formation, according to the current nomenclature. The age of the formation was long debated because Olson based part of his argument on fragmentary fossils that he interpreted as therapsids, an interpretation that was not widely accepted. Worse, one of them, Watongia, was later shown to be a varanopid.
The El Reno Group is a geologic group in Oklahoma. It preserves fossils dating back to the Permian period. The Chickasha Formation, which is part of this group, contains the geologically most recent Permian continental vertebrates (Roadian) known from North America. These include one of the most recent lepospondyls, a dissorophoid, and some fragmentary fossils of Steppesaurus that Everett C. Olson interpreted as one of the oldest known therapsids, an interpretation that has not been widely accepted.
The Arroyo Formation, sometimes termed the Lower Clear Fork Formation, is a geologic formation in Texas. It preserves fossils dating back to the Kungurian stage of the Permian period. It is the lower-most portion of the Clear Fork Group, part of a series of fossiliferous Permian strata in the south-central United States known as the red beds.
The Vale Formation is a geological formation in north-central Texas, a component of the Texas red beds preserving sediments and fossils from the Early Permian Leonardian series. It occupies the middle part of the Clear Fork Group, above the Arroyo Formation and below the Choza Formation. Some sources consider the Vale Formation to be merely an informal subunit of the Clear Fork Formation, thus renaming it to the Middle Clear Fork Formation.
The San Angelo Formation is a geologic formation in Texas. It preserves fossils dating back to the Permian period. Along with the Chickasha Formation is one of the two geologically youngest formations in North America to preserve fossils of caseids, and it is the youngest one to preserve remains of undoubted sphenacodontids, namely, Dimetrodon angelensis.
The Pease River Group is a geologic group in Texas Red Beds. It preserves fossils dating back to the Permian period, including some of the geologically most recent continental and coastal vertebrates of the Permian in North America. These are preserved in the San Angelo Formation, which is probably of early Roadian age. They include several fragmentary fossils that Everett C. Olson interpreted as the earliest therapsids, an interpretation that has not been widely accepted.