Hiraiga S - Miyako area [Hiraiga Fm] (Cretaceous of Japan)

Where: Japan (39.9° N, 141.9° E: paleocoordinates 53.1° N, 140.9° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Hiraiga Formation, Late/Upper Aptian (122.5 - 113.0 Ma)

• STRATIGRAPHIC RELATIONS: From the Hiraiga Fm. AGE: Late Aptian; justification for age not reported in text. STRATIGRAPHIC POSITION: Probably derived from the lower cycle of the Hiraiga Fm.

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, fine-grained, calcareous sandstone

• SPECIFIC LITHOLOGY: Calcareous fine-grained sandstone. LITHIFICATION: Lithified, on the basis of figured specimens.

Size class: macrofossils

Collected by Hanai & Kase

• COLLECTOR: T. Hanai and T. Kase. REPOSITORY: Not stated in text.

Primary reference: T. Kase. 1984. Early Cretaceous marine and brackish-water Gastropoda from Japan 1-262 [A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 91290: authorized by Austin Hendy, entered by Austin Hendy on 14.09.2009, edited by Mark Uhen

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for gastropods; other taxa (namely bivalves and foraminifera) often present. NOMENCLATURE: Authoritative publication, with relatively modern nomenclature, and species-resolution identifications.
Echinoidea
 Euechinoidea - Hemicidaridae
Pseudocidaris simulans Nisiyama 1950 sea urchin
 Holectypoida - Holectypidae
"Caenholectypus peridoneus" = Coenholectypus
"Caenholectypus peridoneus" = Coenholectypus sea urchin
 Arbacioida - Arbaciidae
Goniopygus atavus Nisiyama 1950 sea urchin
Gastropoda
 Seguenzioidea - Eucyclidae
Onkospira haipensis n. sp. snail
 Architaenioglossa - Ampullinidae
 Cerithioidea - Turritellidae
Torquesia yaegashii turret shell
 Sorbeoconcha - Naticidae
Gyrodes nagaoi n. sp. moon snail
 Neritoidea - Neritidae
Lissochilus hanaii n. sp. snail