Where: Japan (36.2° N, 138.6° E: paleocoordinates 36.7° N, 138.1° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Maisawa Formation (Motojuku Group), Piacenzian (3.6 - 2.6 Ma)

• The lower part of the Maisawa Formation includes lake deposits consisting of fine-grained muddy tuff, named the "Kabutoiwa Formation" after Mt. Kabutoiwa. Sato (2007) used K-Ar dating to estimate the numerical age of the "Kabutoiwa Formation" to be 3.5 Ma (Late Pliocene).

Environment/lithology: crater lake; lithified, fine-grained, gray, muddy tuff

Size class: macrofossils

Preservation: adpression

Collection methods: Repository: Gunma Museum of Natural History (GMNH)

Primary reference: H. Aiba, Y. Takahashi, and Y. Sakamaki. 2023. A new species of fossil Nymphalidae (Lepidoptera, Papilionoidea) from the Upper Pliocene Motojuku Group, Gunma Prefecture, Japan. Paleontological Research 27:441-450 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 229456: authorized by Matthew Clapham, entered by Matthew Clapham on 11.03.2023

Creative Commons license: CC BY (attribution)