Kuji amber (Cretaceous to of Japan)

Where: Japan (40.2° N, 141.8° E: paleocoordinates 52.1° N, 130.7° E)

When: Late/Upper Coniacian to Late/Upper Coniacian (89.3 - 83.5 Ma)

• The Kuji amber-bearing deposits are from the Upper Cretaceous Tamagawa Formation of the Kuji Group, the age of Kuji amber matrix from this locality has been estimated to be 83–90 Ma (Umetsu and Kurita 2007; Katagiri et al. 2013; Uno et al. 2018). Recently it was indicated that the age of Kuji amber matrix is dated to the middle Santonian, ca. 85.9 ± 0.7 Ma based on a U–Pb radiometric dating of zircon crystals of the volcaniclastic matrix (Arimoto et al. 2018). [Coniacian-Santonian boundary placed at 85.8 Ma, so Late Coniacian/Early Santonian is used for age]

Environment/lithology: terrestrial; amber

Size classes: macrofossils, mesofossils

Preservation: amber

Collection methods: Repository: Laboratory of Evolutional Ecology, Faculty of Agriculture and Life Sciences, Hirosaki University; Kuji Amber Museum

Primary reference: V. Fursov, Y. Shirota, T. Nomiya and K. Yamagishi. 2002. New fossil mymarommatid species, Palaeomymar japonicum sp. nov. (Hymenoptera: Mymarommatidae), discovered in Cretaceous amber from Japan. Entomological Science 5:51-54 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 138803: authorized by Matthew Clapham, entered by Matthew Clapham on 27.01.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

 Hymenoptera - Mymarommatidae
"Palaeomymar japonicum n. sp." = Archaeromma japonicum
"Palaeomymar japonicum n. sp." = Archaeromma japonicum Fursov et al. 2002 false fairy wasp
 Neuroptera - Rhachiberothidae
Kujiberotha teruyukii n. gen. n. sp.
Kujiberotha teruyukii n. gen. n. sp. Nakamine and Yamamoto 2018 thorny lacewing