Where: Japan (36.1° N, 136.9° E: paleocoordinates 43.5° N, 139.0° E)

• outcrop-level geographic resolution

When: Mitarai Formation (Tetori Group), Berriasian (145.0 - 139.8 Ma)

• STRATIGRAPHIC RELATIONS: From the Mitarai Fm of the Kuzuryu Subgroup, Tetori Group. AGE: ?Berriasian. The Mitarai Formation was previously assigned to the Middle Jurassic on the basis of a single ammonite species, Lilloetia sp. (Sato and Kanie, 1963), or to the Upper Jurassic by Komatsu et al. (2001) based on bivalves. However, the discovery of new ammonites (berriasellids) and a revision of the formerly described species suggest that the formation is, in fact, Tithonian–Berriasian (Sato et al., 2003). Radiometric U-Pb dating of zircons within tuff beds from the Mitarai Formation give an absolute date of 129.8 ／+ − 1.0 Ma, that is, Hauterivian–Barremian (Kusuhsahi et al., 2006). This data and the recent discovery of a single ammonite, Neocosmoceras sp., that was likely to have been collected from the Mitarai quarry suggests a Berriasian age (Sato et al., 2008), although further evidence is needed to corroborate this determination. STRATIGRAPHIC POSITION: The crinoid remains are from the uppermost layer within a black sandy shale and occur with a rich associated fauna of bivalves (Inoceramus sp., Modiolus sp.), gastropods, belemnites and plant remains (Nomura, 1969).

• bed-level stratigraphic resolution

Environment/lithology: offshore; lithified, black, sandy shale

Size classes: macrofossils, mesofossils

Collection methods: bulk, surface (in situ),

• COLLECTOR: Not stated in text. REPOSITORY: University Museum, University of Tokyo (UMUT-ME).

Primary reference: A. W. Hunter, T. Oji, T. M. Ewin and K. Kitazawa. 2011. Chariocrinus japonicus, a new species of isocrinid crinoid (Articulata) from the Lower Cretaceous of Takayama City, central Japan. Bulletin of the Mizunami Fossil Museum (37)115-121 [A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 161967: authorized by Austin Hendy, entered by Austin Hendy on 16.09.2014

Creative Commons license: CC BY (attribution)