# List of archosaurs of the Chinle Formation

The Chinle Formation is an Upper Triassic continental geologic formation in the western United States which has yielded fossils of many archosaurs: a group of vertebrates that includes crocodiles, pterosaurs, dinosaurs (including birds), and other extinct relatives. This is a list of all archosaurs from the formation, including suchians (crocodilian relatives) and avemetatarsalians (dinosaurs, pterosaurs, and their relatives), as well as the abundant crocodilian-like phytosaurs, which may either be true archosaurs or very close relatives of Archosauria.

## Phytosaurs

Phytosaurs of the Chinle Formation :
| Genus | Species | State | Member | Abundance | Notes | Images |
| Leptosuchus | L. crosbiensis | Arizona | Sonsela Blue Mesa Mesa Redondo | | | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Smilosuchus | S. adamanensis | Arizona | Sonsela Blue Mesa Mesa Redondo | Known from a single skull | Previously referred to Leptosuchus, actually referable to Smilosuchus. | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Smilosuchus | S. gregorii | Arizona | Sonsela Blue Mesa Mesa Redondo | Known from a handful of skulls. | A basal leptosuchomorph. | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Smilosuchus | S. lithodendrorum | Arizona | Blue Mesa | Known from only one skull. | Previously considered synonymous with S. adamanensis. | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| cf. Paleorhinus | Indeterminate | Arizona | Mesa Redondo | | | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Machaeroprosopus | M. buceros | Arizona | Owl Rock Petrified Forest Sonsela | | | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Machaeroprosopus | M. mccauleyi | Arizona | Owl Rock Petrified Forest Sonsela | | | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Machaeroprosopus | M. pristinus | Arizona | Owl Rock Petrified Forest Sonsela | | | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Pravusuchus | P. hortus | Arizona | Sonsela | Three skulls. | A leptosuchomorph phytosaur closely related to Mystriosuchini or Nicrosaurus. | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Protome | P. batalaria | Arizona | Sonsela | Partial skull and jaw. | A phytosaur originally described as a juvenile Leptosuchus, but probably an unrelated non-leptosuchomorph or mystriosuchin. | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |
| Redondasaurus | R. gregorii | Arizona Utah | "Siltstone" / Rock Point Petrified Forest Church Rock | | A large late-surviving mystriosuchin phytosaur closely related to Machaeroprosopus (formerly known as Pseudopalatus), and often considered a subgenus of that taxon. | Smilosuchus adamanensis Smilosuchus gregorii Paleorhinus Protome batalaria |

## Suchians
### Aetosaurs

| Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon | Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited. |
Aetosaurs of the Chinle Formation :
| Genus | Species | State | Member | Abundance | Notes | Images |
| Adamanasuchus | A. eisenhardtae | Arizona | Blue Mesa | Osteoderms and skull and postcranial fragments. | A basal desmatosuchine related to Calyptosuchus and Scutarx. | Desmatosuchus spurensis Typothorax coccinarum |
| Calyptosuchus | C. wellesi | Arizona | Blue Mesa | Common, although "non-armor material is comparatively rare". | A basal desmatosuchine originally considered a species of Stagonolepis. | Desmatosuchus spurensis Typothorax coccinarum |
| Desmatosuchus | D. spurensis | Arizona | Blue Mesa | Numerous osteoderms and other skeletal material | A large desmatosuchin which was fairly common in the lower part of the Chinle Formation. Prior to 2008, fossils of D. spurensis were listed as the species D. haplocerus, until it was determined that D. haplocerus was a species name originally based on undiagnostic fossils. | Desmatosuchus spurensis Typothorax coccinarum |
| Desmatosuchus | D. smalli | Arizona | Sonsela? | A single lateral osteoderm. | A desmatosuchin which is very rare in the Chinle Formation. One of the youngest known occurrences of the genus Desmatosuchus. | Desmatosuchus spurensis Typothorax coccinarum |
| Paratypothorax | P. andressorum | Arizona | Blue Mesa Sonsela | Osteoderms | A significant number of researchers feel that the North American material referred to the German Paratypothorax species P. andressorum by Hunt and Lucas in 1992 is actually distinct. | Desmatosuchus spurensis Typothorax coccinarum |
| Paratypothorax | Indeterminate | Arizona New Mexico | Sonsela | Osteoderms and minor postcranial fragments. | A paratypothoracin typothoracine known from isolated material similar to more complete specimens from Germany. | Desmatosuchus spurensis Typothorax coccinarum |
| Rioarribasuchus | R. chamaensis | Arizona New Mexico | Petrified Forest Sonsela | Osteoderms and possible ankle and vertebrae remains. | A late-surviving paratypothoracin typothoracine. Originally referred to Desmatosuchus, but later reinterpreted as a relative of Paratypothorax based on a phylogenetic analysis performed on the remains by Parker in 2003. New genus names were erected independently by Parker (coining the name Heliocanthus) and Lucas et al. (coining the name Rioarribasuchus), prompting an investigation into reports of unethical taxonomic claim-jumping. | Desmatosuchus spurensis Typothorax coccinarum |
| Scutarx | S. deltatylus | Arizona | Sonsela | Four partial skeletons including skull fragments. | A large basal desmatosuchine based on fossils originally referred to "Stagonolepis" (=Calyptosuchus) wellesi, a close relative. Fossils of Scutarx represent the highest stratigraphic occurrence of Stagonolepis-like aetosaurs in Petrified Forest National Park. | Desmatosuchus spurensis Typothorax coccinarum |
| Stenomyti | S. huangae | Colorado | "Red siltstone" | Partial skeleton including a well-preserved skull. | A small aetosaurine similar to Aetosaurus. | Desmatosuchus spurensis Typothorax coccinarum |
| Typothorax | T. coccinarum | Arizona | Owl Rock Petrified Forest Sonsela | Common in the Owl Rock and Petrified Forest Members. | A large, wide-bodied typothoracine abundant throughout the Chinle Formation. Almost all of the known Chinlean Typothorax fossils are isolated whole or fragmentary osteoderms. | Desmatosuchus spurensis Typothorax coccinarum |
| Tecovasuchus | T. chatterjeei | Arizona | Blue Mesa | Osteoderms. | Previously thought to be more widespread in the formation. | Desmatosuchus spurensis Typothorax coccinarum |
| Kryphioparma | K. caerula | Arizona | Blue Mesa | Osteoderms. | Described in 2023, probably related to other typothoracines. | Desmatosuchus spurensis Typothorax coccinarum |

### Crocodylomorphs

Crocodylomorphs of the Chinle Formation :
| Genus | Species | State | Member | Abundance | Notes | Images |
| Hesperosuchus | H. agilis | Arizona | Petrified Forest Blue Mesa Mesa Redondo | | | Hesperosuchus agilis |
| Parrishia | P. mccreai | Arizona | Blue Mesa Mesa Redondo | | | Hesperosuchus agilis |

### Other paracrocodylomorphs

Paracrocodylomorphs of the Chinle Formation :
| Genus | Species | State | Member | Abundance | Notes | Images |
| Effigia | E. okeeffeae | New Mexico | "Siltstone" | | A six-foot-long shuvosaurid from the Coelophysis quarry of Ghost Ranch. | Effigia okeeffeae Poposaurus gracilis Postosuchus kirkpatricki Shuvosaurus inexpectatus |
| Poposaurus | P. gracilis | Arizona | Blue Mesa Mesa Redondo | | | Effigia okeeffeae Poposaurus gracilis Postosuchus kirkpatricki Shuvosaurus inexpectatus |
| Postosuchus | P. kirkpatricki | Arizona | Owl Rock Petrified Forest Sonsela Blue Mesa Mesa Redondo | | | Effigia okeeffeae Poposaurus gracilis Postosuchus kirkpatricki Shuvosaurus inexpectatus |
| Saurosuchus | Indeterminate | Arizona | Blue Mesa | Jaw fragment. | Identified from a fossil which has been reinterpreted as an indeterminate "rauisuchian". | Effigia okeeffeae Poposaurus gracilis Postosuchus kirkpatricki Shuvosaurus inexpectatus |
| Shuvosaurus | S. inexpectatus | Arizona | Owl Rock Petrified Forest Mesa Redondo | | Following a rediagnosis of the genus and species, only shuvosaurid fossils from the Cooper Canyon Formation are reliably identifiable as Shuvosaurus itself. | Effigia okeeffeae Poposaurus gracilis Postosuchus kirkpatricki Shuvosaurus inexpectatus |
| Vivaron | V. haydeni | New Mexico | Petrified Forest | | A large rauisuchid similar to Postosuchus. | Effigia okeeffeae Poposaurus gracilis Postosuchus kirkpatricki Shuvosaurus inexpectatus |

### Other suchians

Miscellaneous suchians of the Chinle Formation :
| Genus | Species | State | Member | Abundance | Notes | Images |
| Acaenasuchus | A. geoffreyi | Arizona | Sonsela Blue Mesa Mesa Redondo | Known from a handful of isolated osteoderms. | A controversial suchian based primarily on osteoderms. Some paleontologists have considered Acaenasuchus to be juvenile Desmatosuchus haplocerus scutes, while others considered it a separate genus of small aetosaurs. Most recently it has been reconsidered an aetosauriform related to, but not within, Aetosauria. It is also related to Revueltosaurus (also from the Chinle) and the armored reptile Euscolosuchus from Virginia. | Revueltosaurus |
| Revueltosaurus | R. callenderi | Arizona | Petrified Forest | | | Revueltosaurus |
| Revueltosaurus | R. hunti | Arizona | Blue Mesa | | | Revueltosaurus |

## Avemetatarsalians
### Basal avemetatarsalians

| Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon | Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited. |
Basal Dinosauriforms of the Chinle Formation :
| Genus | Species | State | Member | Notes | Images |
| Dromomeron | D. romeri | Arizona Colorado New Mexico | Petrified Forest (Hayden Quarry #3) Owl Rock ‘Red siltstone’ | A lagerpetid pterosauromorph found at various Ghost Ranch quarries and elsewhere in the Chinle Formation. | Dromomeron romeri Kwanasaurus williamparkeri |
| Eucoelophysis | E. baldwini | New Mexico | Petrified Forest | A silesaurid dinosauriform closely related to the Polish genus Silesaurus. | Dromomeron romeri Kwanasaurus williamparkeri |
| Kwanasaurus | K. williamparkeri | Colorado | "Red siltstone" | A silesaurid dinosauriform with adaptations for herbivory. | Dromomeron romeri Kwanasaurus williamparkeri |

### Dinosaurs
#### Sauropodomorphs

Prosauropod tracks are present in the Redonda, Sloan Canyon, and Sheep Pen Sandstone formations. Possibly the Rock Point Formation as well. Geographically, the tracks are present in New Mexico.

#### Theropods and near-relatives

Theropod tracks have been found in Utah and New Mexico recovered from the Redonda, Sloan Canyon, and Sheep Pen Sandstone formations. Indeterminate theropod remains are stratigraphically present in the Petrified Forest, Bluewater Creek, and Rock Point members of New Mexico.
Theropods and near-relatives of the Chinle Formation :
| Genus | Species | State | Member | Abundance | Notes | Images |
| Camposaurus | C. arizonensis | Arizona | Bluewater Creek Formation | | A coelophysine coelophysid | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Chindesaurus | C. bryansmalli | Arizona | Petrified Forest | | A large saurischian alternatively considered a herrerasaurid or a theropod related to Tawa hallae. | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Coelophysis | C. bauri | New Mexico | "Siltstone" | | | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Coelophysis | C. sp. | Arizona | Petrified Forest | | Originally assigned to C. bauri, but likely a different taxon. | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Coelophysis | C. longicollis | New Mexico | Petrified Forest | | Now considered a junior synonym of C. bauri. | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Coelophysis | C. willistoni | New Mexico | Petrified Forest | | Now considered a junior synonym of C. bauri. | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Daemonosaurus | D. chauliodus | New Mexico | "Siltstone" | Skull and neck vertebrae fragments | A possible basal theropod with a short skull and enlarged teeth. | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |
| Tawa | T. hallae | New Mexico | Petrified Forest (Hayden Quarry) | | A probable basal theropod showing a mosaic of features similar to neotheropods and herrerasaurids. | Camposaurus arizonensis Chindesaurus bryansmalli (interpreted as a herrerasaurid) Coelophysis bauri Daemonosaurus chauliodus Tawa hallae |