Snow Hill Island Formation

Last updated
Snow Hill Island Formation
Stratigraphic range: Early Maastrichtian
71.2–70.8  Ma
O
S
D
C
P
T
J
K
Pg
N
Snow Hill Island Formation paleoenvironment recon.jpg
Artist's reconstruction of the paleoenvironment of the Snow Hill Island Formation.
Type Geological formation
Unit of Marambio Group
Sub-unitsGamma & Herbert Sound Members
Underlies Lopez de Bertodano Formation
Overlies Santa Marta Formation
Lithology
Primary Sandstone
Other Mudstone
Location
Coordinates 63°54′S57°54′W / 63.9°S 57.9°W / -63.9; -57.9
Approximate paleocoordinates 61°48′S68°30′W / 61.8°S 68.5°W / -61.8; -68.5
Region James Ross Island, James Ross Island group
Country Antarctica
Geologic map of Seymour Island, Antarctica.png
Geologic map of Seymour Island, Antarctica with Snow Hill Island Formation in dark green

The Snow Hill Island Formation is an Early Maastrichtian geologic formation found on James Ross Island, James Ross Island group, Antarctica. [1] Remains of a paravian theropod Imperobator antarcticus [2] have been recovered from it, as well as the elasmarian ornithopods Trinisaura santamartaensis , Biscoveosaurus and Morrosaurus antarcticus , the ankylosaurian Antarctopelta oliveroi , and the shark Notidanodon sp. Alongside these described genera are also the remains of indeterminate elasmosaurids, [3] lithostrotian titanosaurs and an indeterminate pterosaur. [4]

Contents

In the Herbert Sound Member of the Snow Hill Island Formation, bivalves, ammonites, and fish were found. [5]

Fossil content

Vertebrate

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

Plesiosaurs

Plesiosaurs
GenusSpeciesPresenceMaterialNotesImages
Elasmosauridae Gen. et. sp. indet."MLP 11-II-20-4, one cervical vertebra preserving a partial rib; MLP 86-X-28-3, two cervical vertebrae; MLP 86-X-28-(2–6), 10 posterior cervical vertebrae articulated with three pectoral vertebrae, part of two dorsal vertebrae, ribs, and indeterminate fragments." [6]
Vegasaurus V. molyiCape Lamb member, Vega Island.Partial Skeleton (MLP 93-I-5-1).A plesiosaur.
Vegasaurus molyi.png

Mosasaurs

Mosasaurs
GenusSpeciesPresenceMaterialNotesImages
Taniwhasaurus [7] T. antarcticusJames Ross Island.IAA 2000-JR-FSM-1, containing a skull measuring 72 cm (28 in) long, teeth, some vertebrae, and rib fragments.A tylosaur.
Taniwhasaurus Taniwhasaurus.jpg
Taniwhasaurus

Dinosaurs

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Dinosaurs
GenusSpeciesPresenceMaterialNotesImages
Antarcticavis A. capelambensis [8] Cape Lambe Member, Vega Island.Partial Skeleton (SDSM 78147) consists of two thoracic vertebrae, the sternum keel, the right coracoid and shoulder blade, the sternal part of the left coracoid, the right upper arm, parts of the left upper arm, the proximal right ulna, the proximal left ulna and radius (articulated), the proximal right carpometacarpus, the proximal left carpometacarpus, the distal left carpometacarpus, the synsacrum, the right and left thighs, the proximal right tibiotarsus, the right and left distal tibiotarsus, and the proximal right tarsometatarsus.
Antarctopelta A. oliveroiSanta Marta Cove.A partial skeleton (MLP 86-X-28-1) consists of three isolated teeth, part of the lower jaw with another tooth in situ, some other skull fragments, vertebrae of the neck, back, hips and tail, some shoulder and hip bones (scapula, ilium) a thigh bone (femur), foot and hand bones (five metapodials and two phalanges), and numerous pieces of armor.A Parankylosaur
Antarctopelta_Size_Comparison Antarctopelta Size Comparison.svg
Antarctopelta_Size_Comparison
"Biscoveosaurus"IndeterminateCape Lamb Member. [9] [10] Dentaries, teeth, a braincase, parts of the maxillae, forelimb elements, assorted vertebrae, and the pectoral girdle.An ornithopod.
Iguanodontidae IndeterminateCape Lamb Member.
Imperobator I. antarcticusCape Lamb Member, Naze Peninsula. [11] A single specimen that contains skull fragments possibly from the premaxilla, maxilla, and dentary as well as a caudal vertebra, teeth, and pedal elements, UCMP 276000.A large paravian.
Imperobator UDL.png
Morrosaurus M. antarcticusCape Lamb Member. [12] Fragmentary right hind limb. [12] An elasmarian ornithopod.
Morrosaurus.jpg
Titanosauria Indeterminate.Santa Marta Cove.Partial caudal vertebra.
Trinisaura T. santamartaensisSanta Marta Cove, in the lower levels of the formation. [13] MLP08-III-1-1, disarticulated and partial skeleton that includes one incomplete dorsal vertebra, three sacral centra, seven caudal vertebrae; two incomplete dorsal rib shafts, one proximal haemal arch, incomplete right scapulocoracoid, incomplete right humerus, two metacarpals, both ilia, right pubis, right ischium, right femur, right distal tibia, incomplete metatarsal III, first phalanx of pedal digit III, two phalanges of pedal digit IV, and indeterminate fragments.An elasmarian ornithopod.
Trinisaura2.jpg

Fish

Fish
GenusSpeciesPresenceMaterialNotesImages
Chimaera C. zangerliSanta Marta Cove, James Ross Island.A chimaera.
Chlamydoselachus C. thompsoniSanta Marta Cove, James Ross Island.Complete dentition.A frilled shark.
Edaphodon E. snowhillensisHerbert Sound Member. [14] Complete dentition. [14] A large species of chimaera.
Notidanodon N. dentatusCape Lamb Member, Vega Island.A cow shark.

Pterosaur

Pterosaurs
GenusSpeciesPresenceMaterialNotesImages
Pterodactyloidea gen. et sp. Indet.Camp Lamb, Vega Island.MN 7801-V, a wing metacarpal IV. [15] A pterosaur with an estimated wingspan of 4 to 5 meters. [15]

Invertebrate

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Invertebrates
GenusSpeciesPresenceMaterialNotesImages
Fungiacyathus F. deltoidophorusKarlsen Cliffs Member. [16]
Scleractinia indet.UnidentifiableKarlsen Cliffs Member. [16]

See also

Related Research Articles

<i>Antarctopelta</i> Extinct genus of dinosaurs

Antarctopelta is a genus of ankylosaurian dinosaur, a group of large, quadrupedal herbivores, that lived during the Campanian stage of the Late Cretaceous period on what is now James Ross Island, Antarctica. Antarctopelta is the only known ankylosaur from Antarctica and a member of Parankylosauria. The only described specimen was found in 1986, the first dinosaur to be found on the continent, by Argentine geologists Eduardo Olivero and Robert Scasso. The fossils were later described in 2006 by paleontologists Leonardo Salgado and Zulma Gasparini, who named the type species A. oliveroi after Olivero.

<i>Rocasaurus</i> Genus of titanosaurian sauropod from the Late Cretaceous period

Rocasaurus is a genus of titanosaurian sauropod that lived in South America. Rocasaurus was discovered in Argentina in 2000, within the Allen Formation which is dated to be middle Campanian to early Maastrichtian in age. This genus grew up to 8 metres (26 ft) long, making it one of the smaller sauropods. It seems to be closely related to saltasaurid dinosaurs, like Saltasaurus and Neuquensaurus.

<span class="mw-page-title-main">Anacleto Formation</span> Geologic formation in Argentina

The Anacleto Formation is a geologic formation with outcrops in the Argentine Patagonian provinces of Mendoza, Río Negro, and Neuquén. It is the youngest formation within the Neuquén Group and belongs to the Río Colorado Subgroup. Formerly that subgroup was treated as a formation, and the Anacleto Formation was known as the Anacleto Member.

<i>Taniwhasaurus</i> Extinct genus of marine squamate reptiles

Taniwhasaurus is an extinct genus of mosasaurs that lived during the Campanian stage of the Late Cretaceous. It is a member of the subfamily Tylosaurinae, a lineage of mosasaurs characterized by a long toothless conical rostrum. Two valid species are attached to the genus, T. oweni and T. antarcticus, known respectively from the fossil record of present-day New Zealand and Antarctica. Two other species have been nominally classified within the genus, T. 'capensis' and T. 'mikasaensis', recorded in present-day South Africa and Japan, but their attribution remains problematic due to the fragmentary state of their fossils. The generic name literally means "taniwha lizard", referring to a supernatural aquatic creature from Māori mythology.

<span class="mw-page-title-main">La Colonia Formation</span> Geological formation in Argentina

The La Colonia Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.

<span class="mw-page-title-main">Allen Formation</span> Geological formation in Argentina

The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous (middle Campanian to early Maastrichtian. Dinosaur remains are among the fossils that have been recovered from the formation. Indeterminate chelid remains and other vertebrates have also been discovered in this formation.

The Lopez de Bertodano Formation is a geological formation in the James Ross archipelago of the Antarctic Peninsula. The strata date from the end of the Late Cretaceous to the Danian stage of the lower Paleocene, from about 70 to 65.5 million years ago, straddling the Cretaceous-Paleogene boundary.

<span class="mw-page-title-main">Santa Marta Formation</span>

The Santa Marta Formation is a geologic formation in Antarctica. It, along with the Hanson Formation and the Snow Hill Island Formation, are the only formations yet known on the continent where dinosaur fossils have been found. The formation outcrops on James Ross Island off the coast of the northern tip of the Antarctic Peninsula. In its entirety, the Santa Marta Formation is on average one kilometer thick.

<i>Trinisaura</i> Extinct genus of dinosaurs

Trinisaura is a genus of ornithopod dinosaur that lived during the late Campanian stage of the Upper Cretaceous, around 73 to 72 million years ago in what is now James Ross Island off the coast of northern Antarctica near Patagonia. It is known from a single, incomplete postcranial skeleton that includes several vertebrae, a partial pelvis, and nearly complete right hindlimb. The fossils were collected in 2008 by paleontologists Juan Moly and Rodolfo Coria from the sandstone of the Snow Hill Island Formation. It remained undescribed in the collections of the Museo de La Plata until its description by Coria and colleagues in 2013, being the basis of the novel genus and species Trinisaura santamartaensis. The genus name is to commemorate the efforts of Argentine geologist Trinidad "Trini" Diaz and the Latin root -sauros, meaning "lizard". The species name is after Santa Marta Cove, where the fossils were collected.

<i>Morrosaurus</i> Extinct genus of dinosaurs

Morrosaurus is an extinct genus of herbivorous elasmarian dinosaur that lived in the late Cretaceous in Antarctica. The only known species is the type Morrosaurus antarcticus.

<i>Kaikaifilu</i> Extinct genus of marine squamate reptiles

Kaikaifilu is an extinct genus of large mosasaurs that lived during the Late Cretaceous (Maastrichtian) in what is now northern Antarctica. The only species known, K. hervei, was described in 2017 from an incomplete specimen discovered in the López de Bertodano Formation, in Seymour Island, Antarctic Peninsula. The taxon is named in reference to Coi Coi-Vilu, a reptilian ocean deity of the Mapuche cosmology. Early observations of the holotype classify it as a member of the subfamily Tylosaurinae. However, later observations note that several characteristics show that this attribution is problematic.

<i>Kawanectes</i> Extinct genus of reptiles

Kawanectes is a genus of elasmosaurid plesiosaur, a type of long-necked marine reptile, that lived in the marginal marine environment of Late Cretaceous Patagonia. It contains one species, K. lafquenianum, described in 2016 by O'Gorman.

<i>Imperobator</i> Extinct genus of dinosaurs

Imperobator is a genus of paravian theropod, a group of large, three-toed carnivorous dinosaurs, that lived during the Maastrichtian age of the Late Cretaceous period in what is now James Ross Island in Antarctica. Imperobator is one of only two non-avian theropods known from Antarctica, crossing over to the landmass when it was part of Gondwana. The only described specimen was found in 2003 by an expedition launched by the University of California Museum of Paleontology and initially described as a dromaeosaur in 2007. However, later searches reported more fossils from the site including teeth and skull bones. The fossils were formally described as a new genus of giant paravian in 2019.

<i>Niebla antiqua</i> Extinct species of dinosaur

Niebla is a genus of abelisaurid theropod dinosaur from the Late Cretaceous Period (Campanian-Maastrichtian) of Río Negro province, Argentina. The genus contains a single species, Niebla antiqua, and is known from a partial, non-articulated skeleton. The holotype, found in the Allen Formation, represents an adult individual.

<i>Maip</i> Genus of megaraptoran dinosaurs

Maip is a genus of large megaraptorid theropod dinosaur from the Late Cretaceous (Maastrichtian) Chorrillo Formation of Santa Cruz, Argentina. The genus contains a single species, M. macrothorax, known from an incomplete, disarticulated skeleton. Maip may represent the largest megaraptorid known from South America, and possibly the world.

<i>Yatenavis</i> Extinct genus of birds

Yatenavis is an extinct genus of enantiornithine bird from the Late Cretaceous Chorrillo Formation of Santa Cruz Province, Argentina. The genus contains a single species, Y. ieujensis, known from a partial humerus.

Chubutinectes is an extinct genus of elasmosaurid plesiosaur from the Late Cretaceous La Colonia Formation of Argentina. The genus contains a single species, C. carmeloi, known from a partial skeleton and associated gastroliths.

<i>Titanomachya</i> Extinct genus of sauropod dinosaurs

Titanomachya is an extinct genus of titanosaurian sauropod dinosaur from the Late Cretaceous La Colonia Formation of Argentina. The genus contains a single species, T. gimenezi. It is a relatively small titanosaur, weighing around 7.8 tonnes.

Koleken is a genus of carnotaurin abelisaurid from the Maastrichtian La Colonia Formation in the Chubut Province of Argentina. The type and only species is K. inakayali, known from one immature specimen about six years old in minimum age.

References

  1. di Pasquo, M.; Martin, J.E. (2013). "Palynoassemblages Associated with a Theropod Dinosaur from the Snow Hill Island Formation (lower Maastrichtian) at the Naze, James Ross Island, Antarctica". Cretaceous Research. 45: 135–154. Bibcode:2013CrRes..45..135D. doi:10.1016/j.cretres.2013.07.008. hdl: 11336/80121 .
  2. Ely & Case, 2019
  3. O'Gorman, 2012, p.2
  4. Reguero, Marcelo & Gasparini, Zulma & Olivero, Eduardo & Coria, Rodolfo & Fernandez, Marta & O'Gorman, José & Gouiric Cavalli, Soledad & Acosta Hospitaleche, Carolina & Bona, Paula & Iglesias, Ari & Gelfo, Javier N. & Raffi, María & Moly, Juan. (2022). Late Campanian-Early Maastrichtian Vertebrates From The James Ross Basin, West Antarctica: Updated Synthesis, Biostratigraphy, And Paleobiogeography. Anais da Academia Brasileira de Ciências. 20211142. 10.1590/0001-3765202220211142.
  5. O'Gorman, 2012, p.3
  6. O'Gorman, J.P. 2012. The oldest elasmosaurs (Sauropterygia, Plesiosauria) from Antarctica, Santa Marta Formation (upper Coniacian? Santonian-?upper Campanian) and Snow Hill Island Formation (upper Campanian-?lower Maastrichtian), James Ross Island. Polar Research 31. 1–10. Accessed 2019-04-13. doi:10.3402/polar.v31i0.11090
  7. Fernando E. Novas; Marta S. Fernandez; Zulma B. de Gasparini; Juan M. Lirio; Héctor J. Nuñez; Pablo Puerta (2002). "Lakumasaurus antarcticus, n. gen. et sp., a new mosasaur (Reptilia, Squamata) from the Upper Cretaceous of Antarctica". Ameghiniana. 39 (2): 245–249. hdl:11336/136746. S2CID 128304133.
  8. Amanda Cordes-Person; Carolina Acosta Hospitaleche; Judd Case; James Martin (2020). "An enigmatic bird from the lower Maastrichtian of Vega Island, Antarctica". Cretaceous Research. 108: Article 104314. doi:10.1016/j.cretres.2019.104314.
  9. Lamanna, Matthew C.; Case, Judd A.; Roberts, Eric M.; Arbour, Victoria M.; Ely, Ricardo C.; Salisbury, Steven W.; Clarke, Julia A.; Malinzak, D. Edward; West, Abagael R.; O'connor, Patrick M. (2019). "Late Cretaceous non-avian dinosaurs from the James Ross Basin, Antarctica: description of new material, updated synthesis, biostratigraphy, and paleobiogeography". Advances in Polar Science. 30 (3): 228–250. doi:10.13679/j.advps.2019.0007.
  10. Stilwell, Jeffrey D.; Long, John A. (2011-10-12). Frozen in Time: Prehistoric Life in Antarctica. Csiro Publishing. ISBN   978-0-643-10402-0.
  11. Ely, Ricardo C.; Case, Judd A. (2019-09-01). "Phylogeny of a new gigantic paravian (Theropoda; Coelurosauria; Maniraptora) from the Upper Cretaceous of James Ross Island, Antarctica". Cretaceous Research. 101: 1–16. Bibcode:2019CrRes.101....1E. doi: 10.1016/j.cretres.2019.04.003 . ISSN   0195-6671. S2CID   146325060.
  12. 1 2 Rozadilla, Sebastián; Agnolin, Federico L.; Novas, Fernando E.; Aranciaga Rolando, Alexis M.; Motta, Matías J.; Lirio, Juan M.; Isasi, Marcelo P. (2016-01-01). "A new ornithopod (Dinosauria, Ornithischia) from the Upper Cretaceous of Antarctica and its palaeobiogeographical implications". Cretaceous Research. 57: 311–324. Bibcode:2016CrRes..57..311R. doi:10.1016/j.cretres.2015.09.009. ISSN   0195-6671.
  13. Coria, Rodolfo A.; Moly, Juan J.; Reguero, Marcelo; Santillana, Sergio; Marenssi, Sergio (2013-04-01). "A new ornithopod (Dinosauria; Ornithischia) from Antarctica". Cretaceous Research. 41: 186–193. Bibcode:2013CrRes..41..186C. doi:10.1016/j.cretres.2012.12.004. hdl: 11336/76749 . ISSN   0195-6671.
  14. 1 2 Gouiric-Cavalli, Soledad; Cabrera, Daniel A.; Cione, Alberto L.; O'Gorman, José P.; Coria, Rodolfo A.; Fernández, Marta (2015-09-03). "The first record of the chimaeroid genus Edaphodon (Chondrichthyes, Holocephali) from Antarctica (Snow Hill Island Formation, Late Cretaceous, James Ross Island)". Journal of Vertebrate Paleontology. 35 (5): e981128. Bibcode:2015JVPal..35E1128G. doi:10.1080/02724634.2015.981128. hdl: 11336/53488 . ISSN   0272-4634. S2CID   129091192.
  15. 1 2 KELLNER, ALEXANDER W.A.; RODRIGUES, TAISSA; COSTA, FABIANA R.; WEINSCHÜTZ, LUIZ C.; FIGUEIREDO, RODRIGO G.; SOUZA, GEOVANE A. DE; BRUM, ARTHUR S.; ELEUTÉRIO, LÚCIA H.S.; MUELLER, CARSTEN W.; SAYÃO, JULIANA M. (2019). "Pterodactyloid pterosaur bones from Cretaceous deposits of the Antarctic Peninsula". Anais da Academia Brasileira de Ciências. 91 (suppl 2): e20191300. doi: 10.1590/0001-3765201920191300 . ISSN   1678-2690. PMID   31800676. S2CID   208642733.
  16. 1 2 Videira-Santos, Roberto; Tobin, Thomas S.; Scheffler, Sandro Marcelo (2022-08-14). "New occurrences of caryophylliid and fungiacyathid scleractinian corals from the Santa Marta and Snow Hill Island formations (Upper Cretaceous, Antarctica)". Cretaceous Research. 140: 105338. Bibcode:2022CrRes.14005338V. doi:10.1016/j.cretres.2022.105338. ISSN   0195-6671. S2CID   251576799.

Bibliography

Further reading