Okurodani Formation

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Okurodani Formation
Stratigraphic range: Hauterivian–Aptian
Type Geological formation
Unit of Tetori Group
Underlies Amagodani Formation
Overlies Otaniyama Formation
Lithology
Primary Mudstone, Siltstone, Sandstone
Other Tuffite
Location
Region Gifu Prefecture
Country Japan

The Okurodani Formation is an Early Cretaceous geologic formation in central Honshu, Japan. Part of the Tetori Group, it primarily consists of freshwater continental sediments deposited in a floodplain environment, with occasional volcanic tuffite horizons. It has an uncertain age, probably dating between the Hauterivian and Aptian. [1] An indeterminate iguanodontian dinosaur tooth has been recovered from the formation. Many other fossil vertebrates are known from the KO2 locality [2]

Contents

Vertebrate Paleobiota

Amphibians

Amphibians reported from the Okurodani Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Anura IndeterminateKO2 Discoglossid grade
Caudata IndeterminateKO2

Squamates

Squamates reported from the Okurodani Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Sakurasaurus [3] S. shokawensisKO2
?Anguimorpha IndeterminateKO2
Scincomorpha IndeterminateKO2new taxon
Squamata IndeterminateKO22 distinct taxa

Turtles

Turtles reported from the Okurodani Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
cf. Sinemys IndeterminateKO2
Sinochelys IndeterminateKO2 Sinochelyidae
Adocidae IndeterminateKO2
Trionychidae IndeterminateKO2

Choristoderes

Choristoderes reported from the Okurodani Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Monjurosuchus IndeterminateKO2"Association of right squamosal, jugal, quadratojugal, and quadrate"
Monjurosuchus Monjurosuchus.jpg
Monjurosuchus
Shokawa ikoi Shokawa ikoi.jpg
Shokawa ikoi
Shokawa S. ikoiKO2Partial skeleton

See also

Footnotes

  1. Amiot, Romain; Kusuhashi, Nao; Saegusa, Haruo; Shibata, Masateru; Ikegami, Naoki; Shimojima, Shizuo; Sonoda, Teppei; Fourel, François; Ikeda, Tadahiro; Lécuyer, Christophe; Philippe, Marc; Wang, Xu (2021-01-01). "Paleoclimate and ecology of Cretaceous continental ecosystems of Japan inferred from the stable oxygen and carbon isotope compositions of vertebrate bioapatite" (PDF). Journal of Asian Earth Sciences. 205: 104602. Bibcode:2021JAESc.20504602A. doi: 10.1016/j.jseaes.2020.104602 . ISSN   1367-9120.
  2. "KO2 locality, Shokawa Village, Kobudani Valley (Cretaceous to of Japan)". Paleobiology Database.
  3. Evans, Susan E.; Manabe, Makoto (January 1999). "Early Cretaceous Lizards from the Okurodani Formation of Japan". Geobios. 32 (6): 889–899. Bibcode:1999Geobi..32..889E. doi:10.1016/s0016-6995(99)80871-7. ISSN   0016-6995.

References