# Prince Creek Formation

The Prince Creek Formation is a geological formation in Alaska with strata dating to the Early Maastrichtian stage of the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.

## Age

The Prince Creek Formation aged from 80 to 61.7 million years ago. The Kikak-Tegoseak Quarry, where almost all of the dinosaur fossil are from, is located near the middle of the formation, and is about 70.6 to 69.1 million years ago. A lower section, the Kogosukruk Tongue, ages from 72 to 71 million years ago, in the latest Campanian. The youngest part of the formation is Ocean Point, which extends into the Paleogene, at the end of the Danian, based on the age of ostracods and mollusks. In the middle of the formation is the Coleville River Bluff, which extends from the Late Campanian to the Middle/Late Maastrichtian, in which pollen spores are common.

## Habitat

During the time when the Prince Creek Formation was deposited, Earth was going through a greenhouse phase. The rocks in it are alluvial, and were, at the time of burial, on a muddy coastal plain. Leafy plants, roots and pollen are known from the formation, and they show that trampling by dinosaurs was common. It can be proven that during the Maastrichtian the Prince Creek Formation bordered a large body of water by the presence of gypsum and pyrite in nearby rock. Large amounts of plants material are represented by peridonoid dinocysts, algae, fungal hyphae, fern and moss spores, projectates, Wodehouseia edmontonicola, hinterland bisaccate pollen, and pollen from trees, shrubs, and herbs. Based on the large amounts of dinosaur and plant remains, the Prince Creek Formation was deduced to be largely an ice-free woodland with an understory of angiosperm dominated by dinosaurs. The mean temperature was 5 to 6 °C (41 to 43 °F), with the mean temperature during the cold months being 2 to 4 °C (36 to 39 °F) and the mean temperature during the warm months being 10 to 12 °C (50 to 54 °F). Mean annual precipitation was 500 to 1,500 millimetres (20 to 59 in)/year. The paleolatitude of the formation at the time of deposition was around 80°–85°N, high in the Arctic Circle, and would have likely experienced 120 days of winter darkness.

## Vertebrate paleofauna
### Dinosaurs
#### Theropods

Indeterminate tyrannosaurid remains are present, mostly in the form of teeth. The teeth are from the Kikak-Tegoseak Quarry, Liscomb Quarry, and Byers Bed, totaling 8 teeth.
| 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. |
Theropods :
| Genus | Species | Location | Abundance | Notes |
| Dromaeosaurus | D. cf albertensis | Liscomb Quarry Kikak-Tegoseak Quarry Byers Bed | Fossilized teeth | A dromaeosaur. |
| Gruipeda | G. vegrandiunis | Denali Park | | Footprints from a small bird. |
| Ornithomimosauria indet. | Indeterminate | Old Bone Beach | Distal metatarsal IV | Possibly an ornithomimid. |
| Saurornitholestinae indet. | Indeterminate | Pediomys Point - Liscomb Quarry | Small dentary tip from a juvenile. | A new species of dromaeosaurid closely related to Saurornitholestes. |
| Nanuqsaurus | N. hoglundi | Kikak-Tegoseak Quarry | One partial skull including a bone near the front of the maxilla and the front of the lower jaw. | Nanuqsaurus is a tyrannosaurid closely related to Lythronax, Tyrannosaurus, and Tarbosaurus. |
| Saurornitholestes | S. cf. langstoni | Old Bone Beach | Teeth | A dromaeosaur. |
| Troodon | T. sp | Kikak-Tegoseak Quarry Liscomb Quarry Byers Bed Magical Mystery Bar | Dental remains, including teeth. Braincases have also been found. | Remains of T. sp. are approximately 50% larger than specimens from Alberta and Montana. Remains were previously assigned to T. formosus. The most abundant theropod. As of 2011, a dubious genus. |

#### Ornithischians

| 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. |
Ornithischians of the Prince Creek Formation :
| Genus | Species | Location | Abundance | Notes |
| Alaskacephale | A. gangloffi | Kogosukruk Tongue | A squamosal, and the back of the dome. | The first pachycephalosaurine from Alaska discovered. |
| Pachyrhinosaurus | P. perotorum | Kikak-Tegoseak Quarry | An abundance of skeletal remains, including an immature juvenile. | The youngest of the Pachyrhinosaurus species, found in one of the highest latitudes of centrosaurine discoveries. A discovery in the Kikak-Tegoseak Quarry was identified in 2013 as a juvenile of Pachyrhinosaurus perotorum. This discovery shows that the crest started to develop in the front of the snout, then extending farther back until it reaches the eye. |
| Thescelosaurinae indet. | Indeterminate | | Teeth | Remains previously attributed to Thescelosaurus. |
| Leptoceratopsidae | Indeterminate | | Remains of adult and juvenile individuals | |
| Edmontosaurus | E. cf. regalis | Liscomb Bonebed Kikak-Tegoseak Quarry | Disassociated parts from multiple juveniles | Originally identified as a distinct genus (Ugrunaaluk), recent studies have found it ontogenetically indistinguishable from Edmontosaurus. |
| Lambeosaurinae indet. | Indeterminate | Liscomb Bonebed | A supraoccipital | The first confirmed lambeosaurine in the Prince Creek Formation. |
| Ornithopoda indet. | Indeterminate | | One tooth | A single "hypsilophodontid" cheek tooth not attributable to Parksosaurus or Thescelosaurus. |

### Mammals

Mammals of the Prince Creek Formation :
| Genus | Species | Location | Stratigraphic position | Abundance | Notes |
| Cimolodon | C. cf. nitidus | | Lower Maastrichtian | Isolated teeth | A small multituberculate. |
| Gypsonictops | G. sp. | | Lower Maastrichtian | Isolated teeth | A small eutherian. |
| Multituberculata indet. | Indeterminate | | Lower Maastrichtian | Isolated teeth | |
| Marsupialia indet. | Indeterminate | | Lower Maastrichtian | Most common in the Prince Creek Formation | |
| Sikuomys | S. mikros | Lower Colville River. | Upper Campanian | | A tiny eutherian. |
| Unnuakomys | U. hutchisoni | Pediomys Point | Lower Maastrichtian | Over 60 specimens | A small metatherian. |

## Plants

| 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. |
Plants of the Prince Creek Formation :
| Genus | Species | Location | Abundance | Notes |
| Parataxodium | P. wigginsii | Kogosukruk Tongue | | A conifer, one of two from the region. It dominated the forest community of the Kogosukruk Tongue. |
| Hollickia | H. quercifolia | Kogosukruk Tongue | Leaves | An angiosperm, known from leaves. |
| Quereuxia | Q. angulata | Kogosukruk Tongue | | An aquatic angiosperm. |
| Equisetites | E. sp. | Kogosukruk Tongue | | A sphenophyte. |
| Pulcheripollenites | P. krempii | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| cf. Proteacidites | cf. P. sp. | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| cf. Polycingulatisporites | cf. P. reduncus | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Podocarpidites | P. sp. | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Ovoidites | O.? sp. | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Ovoidites | O. sp. | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Ovoidites | O. parvus | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Ovoidites | O. arcticus | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Osmundacidites | O. wellmanii | Coleville River Bluff | Pollen remains | Common in the Early Maastrichtian. Also found in the Schrader Bluff Formation. |
| Mantonisporites | M. sp. indet | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Mancicorpus | M. pseudosenonicus | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Lycopodiacidites | L. sp. | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Lunatadinium | L. dissolutum | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Indeterminate | Indeterminate | Coleville River Bluff | Septate fungal hypha. | Also found in the Schrader Bluff Formation. |
| Leosphaeridia | L. "stellata" | Coleville River Bluff | Pollen remains | Common in the Early Maastrichtian. Also found in the Schrader Bluff Formation. |
| Lairidordites | L. magnus | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Laegivatosporites | L. spp. | Coleville River Bluff | Pollen remains | Indeterminate remains abundant in the Early Maastrichtian, and still numerous in the Late Maastrichtian. Also found in the Schrader Bluff Formation. |
| Laegivatosporites | L. sp. | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Kurtzipites | K. trispissatus | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Integricorpus | I. sp. | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Ischyosporites | I. sp. | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Ischyosporites | I. sp. | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Inundatisporis | I. tappaniae | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Impardecispora | I. marylandensis | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Hannisporis | H. scollardensis | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Hannisporis | H. amplus | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Gleicheniidites | G. senonicus | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Foveosporites | F sp. | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Foraminisporis | F. undulosus | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Fibulapollis | F. scabratus | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Expressipollis | cf. E. accuratus | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Erdtmannipollis | E. procumbentformis | Coleville River Bluff | Pollen spores | Also found in the Schrader Bluff Formation. |
| Dictyophyllidites | D. sp. | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Deltoidospora | D. spp. | Coleville River Bluff | Preserved pollen samples | Very abundant in the early Maastrichtian and Indeterminate level of the formation, becoming rarer until the Middle/Late Maastrichtian. Also found in the Schrader Bluff Formation. |
| Cycadopites | C. fragilis | Coleville River Bluff | Samples of distinct pollen | Also found in the Schrader Bluff Formation. |
| Crassispora? | cf. C. apisulacea | Coleville River Bluff | Pollen samples | Also found in the Schrader Bluff Formation. |
| cf. Converrucosisporites | cf. C. sp. | Coleville River Bluff | Specimens of preserved pollen spores | Also found in the Schrader Bluff Formation. |
| Clavatisporites | C. sp. | Coleville River Bluff | Preserved pollen samples | Also found in the Schrader Bluff Formation. |
| Circulodinium | C. sp. | Coleville River Bluff | Pollen samples | Also found in the Schrader Bluff Formation. |
| Cingutriletes | cf. C. congruens | Coleville River Bluff | Pollen remains | Also found in the Schrader Bluff Formation. |
| Cingulizonates | C. bialatus | Coleville River Bluff | Pollen samples | Also found in the Schrader Bluff Formation. |
| Cicatricosisporites | C. sp. 1 | Coleville River Bluff | Distinct pollen remains | Also found in the Schrader Bluff Formation. |
| Cicatricosisporites | C. spp. | Coleville River Bluff | Preserved pollen | Also found in the Schrader Bluff Formation. |
| Cicatricosisporites | cf. C. dorogensis | Coleville River Bluff | Fossilized pollen spores | Also found in the Schrader Bluff Formation. |
| Cibotiumspora | C. sp. | Coleville Bluff Formation | Pollen spores | Also found in the Schrader Bluff Formation. |
| Camarozonosporites | C. ambigens | Coleville River Bluff | Pollen specimens | Also found in the Schrader Bluff Formation. |
| Botryococcus | B. braunii | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Indeterminate | Indeterminate | Coleville River Bluff | Bissacate gymnosperm pollen | Common and abundant in the Early Maastrichtian, becoming rarer towards the Late Maastrichtian. Also found in the Schrader Bluff Formation. |
| Balmeisporites | B. sp. | Coleville River Bluff | Pollen spore remains | Also found in the Schrader Bluff Formation. |
| Azonia | cf. A. cribrata | Coleville River Bluff | Carbonized pollen | Also found in the Schrader Bluff Formation. |
| Aquilapollenites | A. trialatus | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Aquilapollenites | A. spp. | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Aquilapollenites | A. sp. | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Aquilapollenites | cf. A. dentatus | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Aquilapollenites | A. amygdaloides | Coleville River Bluff | Pollen | Numerous in the Late Campanian, becoming abundant in the Maastrichtian. Also found in the Schrader Bluff Formation. |
| Annulispora | A. sp. | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Anacololsidites | A. sp. 1 | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Anacololsidites | A. sp. | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Alete | A. clavate | Coleville River Formation | Pollen | Also found in the Schrader Bluff Formation. |
| Aequitriradites | cf. A. spinulosus | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |
| Aequitriradite | A. sp. | Coleville River Bluff | Pollen | Also found in the Schrader Bluff Formation. |