Kayenta Formation

From Wikipedia
Kayenta Formation
Stratigraphic range: Sinemurian- Pliensbachian, [1] 196.5–183.0  Ma
Kayenta Formation, Capitol Reef National Park, Utah.
Type Geological formation
Unit of Glen Canyon Group
Underlies Navajo Sandstone
Overlies Wingate Sandstone
Thickness100 to 120 metres (330 to 390 ft)
Primary Sandstone
Other Siltstone, Limestone
Coordinates 37°48′N 110°36′W / 37.8°N 110.6°W / 37.8; -110.6
KAYENTA FORMATION Latitude and Longitude:

37°48′N 110°36′W / 37.8°N 110.6°W / 37.8; -110.6
Country United States
Extentnorthern Arizona, northwest Colorado, Nevada, and Utah
Type section
Named for Kayenta, Arizona
Kayenta Formation west of Tuba City, Arizona.

Kayenta, Arizona is a settlement in the Navajo reservation.

The Kayenta Formation is a geologic layer in the Glen Canyon Group that is spread across the Colorado Plateau province of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah.

This rock formation is particularly prominent in southeastern Utah, where it is seen in the main attractions of a number of national parks and monuments. These include Zion National Park, Capitol Reef National Park, the San Rafael Swell, and Canyonlands National Park.

The Kayenta Formation frequently appears as a thinner dark broken layer below Navajo Sandstone and above Wingate Sandstone (all three formations are in the same group). Together, these three formations can result in immense vertical cliffs of 2,000 feet (610 m) or more. Kayenta layers are typically red to brown in color, forming broken ledges.

Kayenta Formation in Utah

Southeast Utah

Parting lineation, from lower left to upper right; Kayenta Formation, Canyonlands National Park.
The Permian through Jurassic stratigraphy of the Colorado Plateau area of southeastern Utah that makes up much of the famous prominent rock formations in protected areas such as Capitol Reef National Park and Canyonlands National Park. From top to bottom: Rounded tan domes of the Navajo Sandstone, layered red Kayenta Formation, cliff-forming, vertically-jointed, red Wingate Sandstone, slope-forming, purplish Chinle Formation, layered, lighter-red Moenkopi Formation, and white, layered Cutler Formation sandstone. Picture from Glen Canyon National Recreation Area, Utah.

In most sections that include all three geologic formations of the Glen Canyon group the Kayenta is easily recognized. Even at a distance it appears as a dark-red, maroon, or lavender band of thin-bedded material between two thick, massive, cross bedded strata of buff, tan, or light-red color. Its position is also generally marked by a topographic break. Its weak beds form a bench or platform developed by stripping the Navajo sandstone back from the face of the Wingate cliffs. The Kayenta is made up of beds of sandstone, shale, and limestone, all lenticular, uneven at their tops, and discontinuous within short distances. They suggest deposits made by shifting streams of fluctuating volume. The sandstone beds, from less than 1-inch (25 mm) to more than 10 feet (3.0 m) thick, are composed of relatively coarse, well-rounded quartz grains cemented by lime and iron. The thicker beds are indefinitely cross bedded. The shales are essentially fine-grained, very thin sandstones that include lime concretions and balls of consolidated mud. The limestone appears as solid gray-blue beds, a few inches to a few feet thick, and as lenses of limestone conglomerate. Most of the limestone lenses are less than 25 feet (7.6 m) long, but two were traced for nearly 500 feet (150 m) and one for 1,650 feet (500 m).

Viewed as a whole, the Kayenta is readily distinguished from the geologic formations above and below it. It is unlike them in composition, color, manner of bedding, and sedimentary history. Obviously the conditions of sedimentation changed in passing from the Wingate Sandstone formation to the Kayenta and from the Kayenta to the Navajo sandstone, but the nature and regional significance of the changes have not been determined. In some measured sections the transition from Wingate to Kayenta is gradual; the material in the basal Kayenta, beds seems to have been derived from the Wingate immediately below and redeposited with only the discordance characteristic of fluviatile sediments. But in many sections the contact between the two formations is unconformable; the basal Kayenta consists of conglomerate and lenticular sandstone that fills depressions eroded in the underlying beds. In Moqui Canyon near Red Cone Spring nearly 10 feet (3.0 m) of Kayenta limestone conglomerate rests in a long meandering valley cut in Wingate. Likewise, the contact between the Kayenta and the Navajo in places seems to be gradational, but generally a thin jumbled mass of sandstone and shales, chunks of shale and limestone, mud balls, and concretions of lime and iron, lies at the base of the fine-grained, cross bedded Navajo. Mud cracks, a few ripple marks, and incipient drainage channels were observed in the topmost bed of the Kayenta on Red Rock Plateau; and in west Glen Canyon, wide sand-filled cracks appear at the horizon. These features indicate that, in places at least, the Wingate and Kayenta were exposed to erosion before their overlying geologic formations were deposited, are it may be that the range in thickness of the Kayenta thus in part (is) accounted for.

Southwest Utah

The red and mauve Kayenta siltstones and sandstones that form the slopes at base of the Navajo Sandstone cliffs record the record of low to moderate energy streams. Poole (1997) has shown that the streams still flowed toward the east depositing from 150 to 210 m (500 to about 700 feet) of sediment here. The sedimentary structures showing the channel and flood plain deposits of streams are well exposed on switchbacks below the tunnel in Pine Creek Canyon.

In the southeastern part of Zion National Park a stratum of cross bedded sandstone is found roughly halfway between the top and bottom of the Kayenta Formation. It is a "tongue" of sandstone that merges with the Navajo formation east of Kanab, and it shows that desert conditions occurred briefly in this area during Kayenta time. This tongue is the ledge that shades the lower portion of the Emerald Pool Trail, and it is properly called Navajo, not Kayenta.

Fossil mudcracks attest to occasional seasonal climate, and thin limestones and fossilized trails of aquatic snails or worms mark the existence of ponds and lakes. The most interesting fossils, however, are the dinosaur tracks that are relatively common in Kayenta mudstone.

These vary in size, but all seem to be the tracks of three-toed reptiles that walked upright, leaving their tracks in the muds on the flood plains. Unfortunately, so far no bone materials have been found in Washington County that would enable more specific identification.

Apparently during Kayenta time Zion was situated in a climatic belt like that of Senegal with rainy summers and dry winters at the southern edge of a great desert. The influence of the desert was about to predominate, however, as North America drifted northward into the arid desert belt.

Glen Canyon

The Kayenta Formation is approximately 400 feet (120 m) thick and consists of a fine-grained sandstone interbedded with layers of siltstone. The alternation of these units generally produces a series of ledges and slopes between the cliffs of the Navajo and Moenave formation. Dinosaur tracks are fairly common in the siltstone, and fresh water mussels and snails occur but are rare. The Kayenta Formation is colored pale red and adds to the splendor of the Vermilion Cliffs. It accumulated as deposits of rivers.

Vertebrate paleofauna

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.


The "Kayenta Fish Fauna" is the last one recovered from the Glen Canyon Group sequence and it is delimited mostly to the silty facies of the Lower-Middle Part of the formation. [2] This Fauna ir rhater scarce and delimited to several concrete locations with proper lacustrine or fluvial deposition, and are also scarce due to preservation bias. [2] Another aspect that can explain the lack of fish fossils found is the use of different research techniques than used on the Chinle Formation. [2]


Genus Species Location Stratigraphic position Material Notes Images

Hybodontoidea [3]

Hybodontoidea indeterminate

  • Shonto Trading Post, Segi Canyon
  • Ward Terrace

Base of the "typical facies"

UCMP 136104, 136105 + ten uncatalogued specimens, teeth

A Freshwater (Lacustrine or Fluvial) non-neoselachian Shark, incertade sedis inside Hybodontoidea. The remains of Sharks are rather rare on the formation and limited to several locations with typical Lacustrine or fluvial Floodplain Deposition.

Archaeobatidae [4]

Archaeobatidae indeterminate

Gold Spring Quarry 1

Base of the "typical facies"

Isolated Tooth

A Freshwater (Lacustrine or Fluvial) Archaeobatidae Rajiform. Related originally with Micropristis or Libanopristis, and stated to be reworked from younger Cretaceous deposits, was found due to its asymmetrical cusp to fit within the definition of Toarcibatis, being more likely to be native of the formation. [4]


Genus Species Location Stratigraphic position Material Notes Images

Semionotidae [2] [5]

Semionotidae indeterminate

  • Downtown Moab
  • Warner Valley
  • Washington Dome
  • Ward Terrace
  • Warner Valley
  • Zion National Park

Base of the "typical facies"

  • Large (1 m) Complete specimen
  • Isolated Ganoid Scales
  • Teeth

A Freshwater (Lacustrine or Fluvial) Semionotidae Semionotiformes, probably related with the genus Semionotus. Semionotiformes are the only properly identified bony fishes from the formation, including a large specimen exposed at the Dan O’Laurie Museum. [2]

Semionotus is probably related with the Kayenta Seminotiformes

Palaeoniscidae [2] [5]

Palaeoniscidae indeterminate

  • Warner Valley

Base of the "typical facies"

  • Isolated Ganoid Scales
  • Teeth

A Freshwater (Lacustrine or Fluvial) Palaeoniscidae Palaeonisciformes.


Genus Species Location Stratigraphic position Material Notes Images

Ceratodus [2] [6]

Ceratodus guentheri

  • Tsegi Canyon?
  • Little Colorado River Valley on Ward Terrace

Middle “Silty Facies”

  • Single dipnoan tooth plate (MCZ 13865)
  • Uncertain Remains

A Freshwater (Lacustrine or Fluvial) Ceratodontidaean Dipnomorpha. Was described as C. felchi, know from the Upper Jurassic Morrison Formation. It is the main identified Dipnoi specimen from the formation. Other Dipnoi specimens where cited but never described. [6]

Coelacanthidae [6] [5]

Coelacanthidae indeterminate

  • Tsegi Canyon
  • Warner Valley

Base of the "typical facies"

Uncertain Remains

A Freshwater (Lacustrine or Fluvial) Coelacanthidae Coelacanthiformes. Coelacanths are quoted from this zone, but its remains weren't studied.


Genus Species Location Stratigraphic position Material Notes Images

Prosalirus [7]

Prosalirus bitis

Gold Spring Quarry 1

Silty Facies Member

MNA V 8725 (type), MCZ 9324 A, MCZ 9323 A

An Early frog, probably related with Notobatrachidae

Anura [3]

Anura Indeterminate

Gold Spring Quarry 1

Silty Facies Member

MCZ 9019, distal humerus; MCZ 9020-24, ilia

An Early frog, Incertade sedis relationships

Lissamphibia [3]

  • Lissamphibia indeterminate
  • Lissamphibia? indeterminate

Gold Spring Quarry 1

Silty Facies Member

  • MCZ 9025-9028, jaws; MCZ 9031, 9032, vertebrae; MCZ 9035, atlas vertebra; MCZ 9034 + 4 uncatalogued specimens, proximal femora; MCZ 9066, 9067, proximal humeri
  • MCZ 9068-9072, proximal limb bones, possibly humeri

Incertade sedis relationships

Urodela [3]

Urodela indeterminate

Gold Spring Quarry 1

Silty Facies Member

MCZ 9017, 9018, atlas vertebrae

A possible stem salamander, incertade sedis inside Urodela. The oldest record of an Urodelan from North America

Eocaecilia [8]

Eocaecilia micropodia

Gold Spring Quarry 1

Silty Facies Member

MNA V8066 (type); MNA V8053, 8054, 8055, 8057, 8058, 8059, 8060, 8062, 8063, 8064, 8065, 8066, 8067, 8068, 8069, 8070, 8071, 8072, 8073, 9346; MCZ 9011A, 9015, 9095, 9152, 9156. 9158, 9163, 9166, 9167, 9169A, 9171A, 9173, 9231A, 9233, 9235, 9237, 9238A, 9241, 9242

A genus whose relationships are controversial, being considered one of the earliest examples of caecilian, and linked with Gymnophiona.



Genus Species Location Stratigraphic position Material Notes Images

Sphenodontia [3]

Sphenodontia Indeterminate

Gold Spring Quarry 1

Silty Facies

MCZ 9036 through 9040, jaw fragments

An indeterminate Sphenodont

Rhynchocephalia [9]

Rhynchocephalia Indeterminate

Airhead West

Silty Facies

Uncertain Fragments

Uncertain assigantion Rhynchocephalians


Genus Species Location Stratigraphic position Material Notes Images

Testudinata [3] [9]

Testudinata indeterminate

  • Airhead West
  • Gold Spring General
  • Moenkopi Point
  • Valley of the Buttes
  • Paiute Canyon General
  • East Paiute Valley

Silty Facies

Uncertain Fragments

Uncertain assigantion Testudinatans

Cryptodira [10]

Cryptodira indeterminate

Red Knob

Silty Facies

Uncertain Fragments

Uncertain assigantion Testudinatans

Kayentachelys [11]

  • Kayentachelys aprix
  • Kayentachelys sp.
  • Cf.Kayentachelys sp.
  • Gold Spring Quarry 1
  • Gold Spring South
  • Gold Spring General
  • Gold Spring Wash
  • Hummingbird Canyon
  • Ted's Turtle Town
  • Gerald's Turtle

Silty Facies Member

  • TMM 43669-1, 2, 4
  • TMM 436701–3
  • TMM 43656-1, 4
  • TMM 45608-2
  • TMM 43687-1, 4–5, 12, 21, 25–35, 37–41, 47–49, 54
  • TMM 43687-24, 43, 54

An early Testudinatan, considered as a member of the family Kayentachelyidae inside Cryptodira. It is the most abundant vertebrate discovered on the Silty Facies member


Genus Species Location Stratigraphic position Material Notes Images

Crocodylomorpha [10]

  • Crocodylomorpha "undescribed new genus"
  • Crocodylomorpha Indeterminate
  • Airhead West
  • Moenkopi Point, Pumpkin Patch
  • Blue layer, Silty Facies
  • Gold Spring Quarry 1

Silty Facies

  • UCMP 97639, 97640
  • MCZ 9044, dermal armor fragment
  • MCZ 9199, fragment of pseudosuchian dermal scute
  • MCZ 9200, dermal scute, probably Eopneumatosuchus
  • UCMP 136102, fragment of lower jaw

Indeterminate Crocodrylomorphs. Includes a new taxon with skull similar to Orthosuchus stormbergi.

Kayentasuchus [12] [5]

Kayentasuchus walkeri

  • Warner Valley
  • Willow Springs 13

Silty Facies

  • UCMP 131830, nearly complete skeleton
  • UMNH VP 21923

An early Terrestrial or semiterrestrial Crocodrylomorph

Eopneumatosuchus [13]

Eopneumatosuchus colberti

Blue layer, Silty Facies

Silty Facies

  • MNA P1.2460, partial skull
  • Isolated Jaw

An early Terrestrial or semiterrestrial Crocodrylomorph, considered related with marine Teleosaurs

Edentosuchus? [10]

Edentosuchus? "undescribed species 1"

  • Moenkopi Point, Pumpkin Patch
  • Blue layer, Silty Facies

Silty Facies

  • MCZ 8816, mandible
  • UCMP 97638, A skull and articulated mandible
  • UCMP 125395: A cranium.
  • UCMP 125871: Skull with mandibles and one epibranchial lacking the dorsal part of the braincase, articulated with the atlas, axis, and 2 cervical vertebrae.
  • UCMP 125358
  • UCMP 125359: An eroded compressed braincase.
  • UCMP 125872: A right jugal and maxilla in articulation in a large block of unprepared material.
  • UCMP 125870: A very well-preserved braincase
  • UCMP 130082

An early Terrestrial or semiterrestrial hervivorous Crocodrylomorph. Specimens assigned to this controverisal genus wear dentitions with complexity values that are equal to or greater than those of living squamate herbivores. [14]

Calsoyasuchus [15]

Calsoyasuchus valliceps

Adeii Eechii Cliffs, Navajo Nation

Silty Facies

TMM 43631-1 (holotype), partial skull

An early semiaquatic member of the family Goniopholididae


Indeterminate ornithischian remains located in Arizona, USA. [16] Ornithischian tracks located in Arizona, USA. [16] Indeterminate theropod remains located in Arizona, USA. [16] Theropod tracks located in Arizona and Utah, USA. [16] Possible theropod tracks located in Arizona, Colorado, and Utah, USA. [16]

Genus Species Location Stratigraphic position Material Notes Images

Theropoda [9] [17]

Theropoda indeterminate

  • Airhead West
  • Gold Spring General
  • Gold Spring Wash

Silty Facies

  • TMM 43669-10
  • TMM 43687-10, 58, 60, 71, 85, 91, 98, 102, 105, 119

Incertade sedis Theropods, probably Neotheropoda

Coelophysidae [18]

"Shake-N-Bake" coelophysid

  • Rock Head (Bowl Area)
  • Shake-N-Bake

Silty Facies

  • MCZ 8817b dorsal vertebra, partial sacrum, partial pelvis
  • MCZ 8817c two partial mid cervical vertebrae
  • MCZ 8817d incomplete posterior cervical vertebra
  • MCZ 8817e proximal caudal vertebra
  • MCZ 8817f) partial tooth, partial caudal centrum
  • MCZ 8817g) anterior dorsal vertebra
  • MCZ 8817h) incomplete anterior dorsal vertebra
  • MCZ 8817i) partial sacrum
  • MCZ 8817j) proximal femur
  • MCZ 8817k) (robust) proximal femur
  • MCZ 8817l) (gracile) proximal femur
  • MCZ 8817m) distal tibiotarsus
  • MCZ 8817n) distal tibiotarsus, distal fibula
  • MCZ 8817o) distal tibiotarsus, distal fibula
  • MCZ 8817p) distal tibiotarsus
  • MCZ 8817q) distal tibia, partial astragalus
  • MCZ 8817r) partial scapulocoracoid
  • MCZ 8817t) partial scapulocoracoid
  • MCZ 9442; = 8817a) (adult) sacrum, partial ilia, proximal pubes, proximal ischia
  • MCZ 9463; = 8817m-p?) (adult) distal tibiotarsus
  • TMM 43689-4) (adult) proximal tarsometatarsus
  • MNA V3181, pubis

A Coelophysidae Neotheropod.

Coelophysis [19] [20]

C. kayentakatae

  • Rock Head (Bowl Area)
  • Gold Spring Wash
  • Shake-N-Bake

Silty Facies

  • MNI; MNA V2623
  • TMM 43669-3
  • MNA V100, V140

A Coelophysidae Neotheropod. Referred to as Syntarsus by Weishampel et al. [16] Formerly known as Megapnosaurus.

Kayentavenator [21]

Kayentavenator elysiae [21]

Willow Springs

Silty Facies

UCMP V128659, six proximal caudal centra, three centra, two partial neural arches, fragmentary ilium, proximal pubes, pubic shaft fragments, incomplete femora, proximal tibiae, proximal fibula, fragments

A Neotheropod of uncertain relatinships, probably a Coelophysoid. Originally referred to M. kayentakatae by Rowe.

Dilophosaurus [22] [23]

  • Dilophosaurus wetherilli
  • cf. Dilophosaurus wetherilli
  • cf. Dilophosaurus sp.
  • Tuba City, Silty Facies
  • Dilophosaurus Quarry
  • Gold Spring East
  • Gold Spring General
  • Rock Head (Bowl Area)
  • Moenkopi Point, Pumpkin Patch

Silty Facies

  • UCMP 37302 (holotype), nearly complete skeleton. UCMP 37303, partial skeleton; third skeleton eroded and not collected
  • MNA V3145, disal end of R femur
  • TMM 43687-52
  • UCMP 77270
  • UCMP 130053
  • TMM 43646-0, 1
  • TMM 47006-1

An advanced Neotheropod, type member of the Family Dilophosauridae. Dilophosaurus is the main identified dinosaur from the formation, being both the most know and studied. It was among the largest theropods present locally, and very likely an active hunter, rather than a fisher. [23]

Sarahsaurus [24]

Sarahsaurus aurifontanalis [16]

  • Gold Springs
  • Rock Head

Silty Facies

  • TMM 43646–2 partially articulated skeleton
  • TMM 43646–3, partial skeleton
  • MCZ 8893, articulated skull with fragmentary postcranial elements

A Sauropodomorph, member of Massospondylidae. Originally thought to be Massospondylus [16]

Heterodontosauridae [25] [26]

Heterodontosauridae indeterminate

Gold Springs

Silty Facies

Partial Skull & Associated Remains

A Heterodontosaurid of Uncertain placement. Its presence in North America suggest early dispersal of the Family.

Scelidosaurus? [27]

Scelidosaurus? arizonensis

Valley of the Buttes

Silty Facies

UCMP 130056, scutes

A Controversial Thyreophoran, that can belong to the genus Scelidosaurus.

Scutellosaurus [28] [17]

  • Scutellosaurus lawleri
  • cf. Scutellosaurus sp.
  • Scutellosaurus? sp.
  • Paiute North 1
  • West Moenkopi Plateau
  • Paiute Canyon General
  • East Paiute Valley
  • Southwest Paiute Canyon
  • Rock Head
  • Willow Spring General
  • Gold Spring General
  • Gold Spring Quarry
  • Gold Spring South
  • Gerald's Turtle
  • Ted's Turtle Town
  • Hummingbird Canyon

Silty Facies

  • MNA P1.175, almost complete skeleton (holotype)
  • MNA P1.1752, partial skeleton (paratype); TMM 43669-5, 6
  • TMM 43661-1
  • TMM 43691-18
  • TMM 43691-20
  • TMM 43648-13
  • TMM 43663-1
  • TMM 43664-1, 2
  • TMM 47001-1
  • TMM 43690-6
  • TMM 43687-13, 117, 123
  • TMM 43687-9, 16, 17, 22, 42, 50, 57, 75, 81, 96, 112, 114–116, 121–122, 124
  • TMM 45609-10, 11
  • TMM 45609-4, 6
  • TMM 45609-5, 7–9
  • TMM 43669-11
  • TMM 45608-1, 3
  • TMM 43647-7
  • TMM 43656-5
  • TMM 43670-5, 7–8

A Basal Thyreophoran, the most abundant Dinosaur of the Formation


Genus Species Location Stratigraphic position Material Notes Images

Rhamphinion [9] [29]

Rhamphinion jenkinsi [29]

  • Airhead West
  • MCZ 23/78A, Foxtrot Mesa

Silty Facies, Ward Mesa

  • MNA V 4500 (holotype), skull fragments
  • UCMP 128227, left fourth wing metacarpal

A pterosaur, considered a member of the family Dimorphodontidae. Was originally classified as a "rhamphorhynchoid", represents the only major pterosaur identified from the formation and one of the oldest from North America.


Genus Species Location Stratigraphic position Material Notes Images

Tritylodontidae [9] [10]

Tritylodontidae indeterminate

  • Airhead West
  • MCZ, The Landmark
  • Rock Head, general area
  • Willow springs
  • Gold Spring General
  • Gold Spring 1

Silty Facies


Indeterminate Tritylodontidae remains

Dinnebitodon [30]

  • Dinnebitodon amarali [30]
  • Dinnebitodon sp.
  • cf. Dinnebitodon sp.
  • Dinnebito Wash
  • Hummingbird Canyon
  • Gold Spring General

Silty Facies

  • MNA V3222 (Type, partial skull and associated postcrania); MNA V3223, partial skull and scapula
  • MCZ 8831 includes two left dentaries
  • MCZ 8830, Crushed snout
  • TMM 43647-3, 4
  • TMM 43687-7

A relatively large and common Tritylodont

Kayentatherium [31]

  • Kayentatherium wellesi [31]
  • Kayentatherium SP.
  • Cf.Kayentatherium sp.
  • MCZ, The Landmark
  • Hummingbird Canyon
  • Gold Spring General
  • Gold Spring wash
  • Willow Spring General
  • Rock Head, general area

Silty Facies

  • MCZ 8811
  • TMM 43669-9
  • MCZ 8842
  • TMM 43647-9, 10
  • TMM 43687-111

A Large Tritylodont, that has been suggested semiacuatic mode of life. An specimen has been recovered with several associated perinates. [32]

Skull of Kayentatherium

Oligokyphus [33]

  • Oligokyphus sp.
  • cf. Oligokyphus sp.
  • Gold Spring General
  • Gold Spring Quarry 1

Silty Facies

  • TMM 43687-86
  • > 42 specimens

A Tritylodont, also present on coeval deposits from Asia and Europe.

Morganucodon [34]

Morganucodon sp.

  • Gold Spring Quarry 1

Silty Facies

MCZ 20878

A mammaliaform, member of the family Morganucodontidae

Dinnetherium [34]

Dinnetherium nezorum

  • Gold Spring Quarry 1

Silty Facies

MNA V3221; MCZ 20870-20877

A mammaliaform, member of the family Megazostrodontidae

Haramiyidae [34]

Haramiyidae? indet.

  • Gold Spring Quarry 1

Silty Facies

MCZ 20879

Incertade sedis possible Haramiyidae

See also


  1. ^ Weishampel, David B; et al. (2004). "Dinosaur distribution (Early Jurassic, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 530-532. ISBN  0-520-24209-2.
  2. ^ a b c d e f g Milner, A. R., Kirkland, J. I., & Birthisel, T. A. (2006). The geographic distribution and biostratigraphy of Late Triassic-Early Jurassic freshwater fish faunas of the southwestern United States. New Mexico Museum of Natural History and Science Bulletin, 37, 522-529.
  3. ^ a b c d e f CURTIS, K. and PADIAN, K. 1999. An Early Jurassic microvertebrate fauna from the Kayenta Formation of northeastern Arizona: microfaunal change across the Triassic‐Jurassic boundary. Paleobios, 19, 19–37.
  4. ^ a b Delsate, D., & Candoni, L. (2001). Description de nouveaux morphotypes dentaires de Batomorphii toarciens (Jurassique inférieur) du Bassin de Paris: Archaeobatidae nov. fam. Bulletin-Société Des Naturalistes Luxembourgeois, 131-144.
  5. ^ a b c d Gay, R. J., & Milner, A. R. (2015). The first report of an archosaur from the Kayenta Formation of Washington County, Utah (No. e1048). PeerJ PrePrints.
  6. ^ a b c Milner, A. R., & Kirkland, J. I. (2006). Preliminary review of the early Jurassic (Hettangian) freshwater Lake Dixie fish fauna in the Whitmore Point Member, Moenave Formation in southwest Utah. New Mexico Museum of Natural History and Science Bulletin, 37, 510-521.
  7. ^ Shubin, N. H., & Jenkins, F. A. (1995). An early Jurassic jumping frog. Nature, 377(6544), 49-52.
  8. ^ F. A. Jenkins and D. M. Walsh. 1993. An Early Jurassic caecilian with limbs. Nature 365:246-250
  9. ^ a b c d e K. Padian. 1984. Pterosaur remains from the Kayenta Formation (?Early Jurassic) of Arizona . Palaeontology 27(2):407-413
  10. ^ a b c d J. M. Clark and D. E. Fastovsky. 1986. Vertebrate biostratigraphy of the Glen Canyon Group in northern Arizona. The Beginning of the Age of the Dinosaurs: Faunal change across the Triassic-Jurassic boundary, N. C. Fraser and H.-D. Sues (eds.), Cambridge University Press 285-301
  11. ^ Gafney, E., Hutchinson, H., Jenkins, F., and Meeker, L. 1987. Modern turtle origins; the oldest known cryptodire. Science 237: p. 289-291.
  12. ^ Clark, James M.; and Sues, Hans-Dieter (2002). "Two new species of basal crocodylomorphs and the status of the Sphenosuchia". Zoological Journal of the Linnean Society 136: 77−96.
  13. ^ Crompton, A. W. and Smith, K. K. (1980). A new genus and species from the Kayenta Formation (Late Triassic?) of Northern Arizona. In Jacobs, L (ed.), Aspects of Vertebrate History Flagstaff: Museum of Northern Arizona Press, pp. 193-217.
  14. ^ Melstrom, K. M., & Irmis, R. B. (2019). Repeated evolution of herbivorous crocodyliforms during the age of dinosaurs. Current Biology, 29(14), 2389-2395.
  15. ^ Tykoski, Ronald S.; Rowe, Timothy B.; Ketcham, Richard A.; Colbert, Matthew W. (2002). "Calsoyasuchus valliceps, a new crocodyliform from the Early Jurassic Kayenta Formation of Arizona" (PDF). Journal of Vertebrate Paleontology. 22 (3): 593–611. doi:10.1671/0272-4634(2002)022[0593:CVANCF]2.0.CO;2.
  16. ^ a b c d e f g h Weishampel, David B; et al. (2004). "Dinosaur distribution (Early Jurassic, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 530–532. ISBN  0-520-24209-2.
  17. ^ a b B. T. Breeden and T. B. Rowe. 2020. New specimens of Scutellosaurus lawleri Colbert,1981, from the Lower Jurassic Kayenta Formation in Arizona elucidate the early evolution of thyreophoran dinosaurs. Journal of Vertebrate Paleontology 40(4):e1791894:1-32
  18. ^ Tykoski, 1997. A new ceratosaurid theropod from the Early Jurassic Kayenta Formation of Northern Arizona. Journal of Vertebrate Paleontology. 17(3), 81A-82A
  19. ^ Rowe, 1989. A new species of the theropod dinosaur Syntarsus from the Early Jurassic Kayenta Formation of Arizona. Journal of Vertebrate Paleontology. 9(2), 125-136.
  20. ^ Bristowe, A. & M.A. Raath (2004). "A juvenile coelophysoid skull from the Early Jurassic of Zimbabwe, and the synonymy of Coelophysis and Syntarsus.(USA)". Palaeontologica Africana. 40 (40): 31–41.CS1 maint: uses authors parameter ( link)
  21. ^ a b Gay, Robert J. (2010). "Kayentavenator elysiae, a new Tetanuran from the Early Jurassic of Arizona" In: Notes on Early Jurassic Theropods. Lulu Press. Pp. 23-36. ISBN  978-0-557-46616-0.
  22. ^ Welles, 1954. New Jurassic dinosaur from the Kayenta Formation of Arizona. Bulletin of the Geological Society of America. 65, 591-598.
  23. ^ a b A. D. Marsh and T. B. Rowe. 2020. A comprehensive anatomical and phylogenetic evaluation of Dilophosaurus wetherilli (Dinosauria, Theropoda) with descriptions of new specimens from the Kayenta Formation of northern Arizona. Journal of Paleontology 94(Memoir 78):1-103
  24. ^ Marsh, A. D., & Rowe, T. B. (2018). Anatomy and systematics of the sauropodomorph Sarahsaurus aurifontanalis from the Early Jurassic Kayenta Formation. PloS one, 13(10), e0204007.
  25. ^ Attridge J, Crompton AW, Jenkins FA Jr (1985) The southern African Liassic prosauropod Massospondylus discovered in North America. J Vertebr Paleontol 5:128–132
  26. ^ Sereno, P. C. (2012). Taxonomy, morphology, masticatory function and phylogeny of heterodontosaurid dinosaurs. ZooKeys, (226), 1.
  27. ^ Padian, K. (1989). Presence of the dinosaur Scelidosaurus indicates Jurassic age for the Kayenta Formation (Glen Canyon Group, northern Arizona). Geology, 17(5), 438-441.
  28. ^ Rosenbaum, J. N., & Padian, K. E. V. I. N. (2000). New material of the basal thyreophoran Scutellosaurus lawleri from the Kayenta Formation (Lower Jurassic) of Arizona. PaleoBios, 20(1), 13-23.
  29. ^ a b Wellnhofer, Peter (1991). "Summary of Lower Jurassic Pterosaurs." The Illustrated Encyclopedia of Pterosaurs. London, UK: Salamander Books Limited. p. 79. ISBN  0-86101-566-5.
  30. ^ a b Sues, Hans-Dieter 1986. Dinnebitodon amarali, a new tritylodont (Synapdsida) from the lower Jurassic of western North America. Journal of Paleontology v. 60 no. 3. p. 758-762.
  31. ^ a b Sues, Hans-Dieter & F. A. Jenkins. 2006. The Postcranial Skeleton of Kayentatherium Wellesi from the Lower Jurassic Kayenta Formation of Arizona and the Phylogenetic Significance of Postcranial Features in Tritylodontid Cynodonts In: Carrano, Matthew T., Gaudin, T. J., Blob, R. W. and Wible, J. R., Amniote Paleobiology: Perspectivers on the Evolution of Mammals, Birds, and Reptiles: The University of Chicago Press. pp. 114-152.
  32. ^ Hoffman, E. A., & Rowe, T. B. (2018). Jurassic stem-mammal perinates and the origin of mammalian reproduction and growth. Nature, 561(7721), 104-108.
  33. ^ Palmer, D., ed (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 193. ISBN  1-84028-152-9.
  34. ^ a b c Jenkins, F. A., Crompton, A. W., & Downs, W. R. (1983). Mesozoic mammals from Arizona: new evidence on mammalian evolution. Science, 222(4629), 1233-1235.


External links