Where: Japan (36.0° N, 138.7° E: paleocoordinates 46.7° N, 140.5° E)

• coordinate estimated from map

• local area-level geographic resolution

When: Ishido Formation (Sanchu Group), Barremian (129.4 - 125.0 Ma)

• The "Sanchu Cretaceous" has been subdivided by many workers into component formations in ascending order: Shiroi (non-marine), Ishido, Sebayashi, and Sanyama Fms. The present author uses a three part numbering scheme based on Hisada et al., (1992), for which this collection is derived from unit 1. The Ishido Fm (correlated by the PBDB enterer to unit 1) contains a Late Hauterivian to Late Barremaian ammonite fauna. Upper units may range from Barremian to Early Aptian based on ammonite and radiolaria faunas (Sashida et al., 1989).

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, fine-grained, silty, conglomeratic sandstone and medium-grained sandstone

Size class: macrofossils

Collection methods: quarrying,

• Collected by the authors (Yamagiwa, Hisada, and Tamura) during mid-1990's. Collections reposited in National Science Museum, Tokyo, Japan.

Primary reference: N. Yamagiwa, K. Hisada, and M. Tamura. 1998. Early Cretaceous Hexacorals from the western part of the Sanchu area, Kanto Mountains. Bulletin of the Natural Science Museum, Tokyo, Series C 24(1-2):55-66 [A. Miller/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 55539: authorized by Austin Hendy, entered by Austin Hendy on 31.10.2005

Creative Commons license: CC BY (attribution)