Hn0320 - 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 - 112.0 Ma)

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

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, bioturbated, gray, sandy siltstone and lithified, coarse-grained, shelly/skeletal sandstone

• SPECIFIC LITHOLOGY: Bioturbated gray sandy siltstone of 2 m thick, interbedded between oyster-bearing coarse-grained sandstone bed about 80 cm in thickness, interbedded between upper silty fine-grained sandstone and lower crinoidal-bearing laminated fine-grained sandstone bed; burrows of about 1 cm in diameter abundant in upper and lower parts of this bed. LITHIFICATION: Lithified, on the basis of figured specimens.

Size class: macrofossils

Collected by Kase

• COLLECTOR: 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 91257: authorized by Austin Hendy, entered by Austin Hendy on 13.09.2009

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.
Bivalvia
 Ostreoida -
"Ostreoida indet." = Ostreida
"Ostreoida indet." = Ostreida FĂ«russac 1822 oyster
 Carditida - Crassatellidae
 Hiatellida - Hiatellidae
Panopea (Myopsis) plicata Sowerby 1829 clam
 Pholadomyida - Pholadomyidae
 Thraciida - Thraciidae
Thracia sp. Blainville 1824 clam
 Trigoniida - Megatrigonioidae
Gastropoda
 Heterostropha - Nerineidae