Hn4151 - Miyako area [Hiraiga Fm] (Cretaceous of Japan)

Where: Japan (39.8° N, 142.0° E: paleocoordinates 53.0° N, 141.0° 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: From the lower part within the Hiraiga Fm.

• bed-level stratigraphic resolution

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

• SPECIFIC LITHOLOGY: Calcareous fine-grained sandstone including cobble- to boulder-sized nodules; nodules consist of varicolored calcareous fine-grained sandstone with carbonized plant fragments and small-sized bivalves, gastropods, and ammonites. LITHIFICATION: Lithified, on the basis of figured specimens.

Size class: macrofossils

Preservation: concretion

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 91303: authorized by Austin Hendy, entered by Austin Hendy on 14.09.2009

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.
unclassified
  -
Cephalopoda
 Ammonitida - Douvilleiceratidae
Gastropoda
 Trochoidea - Turbinidae
 Vetigastropoda - Cirridae
Shikamacirrus nipponicus n. gen. n. sp.
Shikamacirrus nipponicus n. gen. n. sp. snail
 Heterostropha - Acteonidae
? Acteon sp. Montfort 1810 snail
 Heterostropha - Ringiculidae
Bivalvia
 Ostreida - Bakevelliidae
 Cardiida - Veneridae
 Carditida - Astartidae
 Trigoniida - Megatrigonioidae