Ikushumbetsu Area, Mikasa Sandstone, Hokkaido (Cretaceous of Japan)

Where: Ishikari, Japan (43.3° N, 142.0° E: paleocoordinates 51.3° N, 134.7° E)

• coordinate estimated from map

• local area-level geographic resolution

When: Mikasa Sandstone Formation (Middle Yezo Group), Turonian (93.9 - 89.8 Ma)

• formation-level stratigraphic resolution

Environment/lithology: foreshore; fine-grained sandstone and mudstone

Size class: macrofossils

Preservation: cast, mold/impression

Primary reference: I. Hayami. 1975. A systematic survey of the Mesozoic Bivalvia from Japan. The University Museum, The University of Tokyo, Bulletin (10) [M. Aberhan/S. Nurnberg/S. Nurnberg]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 39577: authorized by Martin Aberhan, entered by Sabine Nürnberg on 31.05.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Bivalvia
 Cardiida - Veneridae
 Lucinida - Mactromyidae
Thetis japonica Hayami 1975 clam
 Carditida - Crassatellidae
Anthonya apicalis clam
subsp. apicalis
 Trigoniida - Myophorelloidae
 Trigoniida - Megatrigonioidae
 Trigoniida - Trigoniidae
 Mytilida - Crenellidae
 Pectinida - Entoliidae
 Ostreida - Bakevelliidae
 Arcida - Glycymerididae
? Trigonarca sp., "Glycymeris (Glycymerita) katsurazawensis" = Glycymerita
? Trigonarca sp. Conrad 1862 clam
"Glycymeris (Glycymerita) katsurazawensis" = Glycymerita clam
 Arcida - Cucullaeidae
Cucullaea (Idonearca) ezoensis, "Cucullaea (Idonearca) aff. truncata" = Cucullaea (Cyphoxis) truncata
Cucullaea (Idonearca) ezoensis Yabe and Nagao 1928 clam
subsp. ezoensis
"Cucullaea (Idonearca) aff. truncata" = Cucullaea (Cyphoxis) truncata Gabb 1864 clam