Where: Japan (42.2° N, 142.8° E)

• Paleocoordinates: 39.3° N, 177.8° E (Wright 2013)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Tsukenai Formation (Yezo Group), Aptian (125.0 - 113.0 Ma)

• Detailed biostratigraphic position unknown, but correlation indicates a late early to early late Aptian age for these taxa.

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified, gray, sandy siltstone

Size class: macrofossils

Collected by M. Futakami, Y. Kawashita in 1994

• Repository: National Museum of Nature and Science, Tsukuba, Ibaraki

Primary reference: M. Futakami. 2018. Aptian ammonite fauna from the Yezo Group of the Urakawa area in Hokkaido, Japan. Cretaceous Research 89:224-234 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 180422: authorized by Matthew Clapham, entered by Matthew Clapham on 16.07.2016

Creative Commons license: CC0 (CC0)