ammonites
Nakao Forestry Road Locality 102 (Jurassic to of Japan)

Where: Yamaguchi Prefecture, Japan (34.1° N, 131.0° E: paleocoordinates 40.9° N, 133.5° E)

• coordinate stated in text

When: Kiyosue Formation (Toyonishi Group), Callovian to Callovian (164.7 - 140.2 Ma)

• The dating of this formaion has not been performed, but the age of theKwanmon Group overlying this formation is suggested to be older than 134 Ma indicating that this formation is older than Valanginian. This formation is not older than the Callovian because the Utano Fm. that underlies the Kiyosue Fm. is dated as Bathonian to Callovian. Thus, the Kiyosue Fm. is possibly also Callovian in age, and therefore Middle Jurassic, contrary to the title of the article.

Environment/lithology: fluvial; siltstone

• "The fossils occurred in a siltstone intercalating lenticular very fine sandstones with ripple laminae, and their occurence is limited to one horizon ca. 50 cm thick. The lithofacies of this formation is characterized by very fine sandstones with climbing ripple laminae, mudstones with lenticular very fine sandstones, and mudstones intruded by upright root fossils, indicating a fluvial origin."

Size class: microfossils

Preservation: mold/impression, adpression, original carbon, original sporopollenin

Collection methods: surface (in situ), chemical, peel or thin section,

• The specimens were all collected from a single ca. 200 x 200 x 300 cm slab.

Primary reference: T. Yamada and M. Kato. 2002. Regnellites nagashimae gen. et sp. nov., the oldest macrofossil of Marsileaceae from the upper Jurassic to lower Cretaceous of western Japan. International Journal of Plant Sciences 163(5):715-723 [R. Lupia/B. Wilborn/B. Wilborn] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 31669: authorized by Rick Lupia, entered by Brooke Wilborn on 21.05.2003