Kaseki-Kabe, Kuwajima, Shiramine-mura (Cretaceous of Japan)

Where: Ishikawa, Japan (36.2° N, 136.6° E: paleocoordinates 46.6° N, 138.1° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Kuwajima Formation (Tetori Group), Barremian (129.4 - 125.0 Ma)

• Kuwajima Alternation, Itoshiro Subgroup, Tetori Group. Radiometric dating recently reported from the Tetori Group suggested that the age of the Kuwajima Formation is younger than the early Neocomian, probably somewhere between the Barremian to early Aptian (Matsumoto et al. 2006). The zircon -Pb age of 130.7 ± 0.8 (2 SE) Ma from a tuff intercalated in the lower part of the Kuwajima Formation reported by Matsumoto et al. (2006) indicates that the Kuwajima Formation is younger than the latest Hauterivian in age (Gradstein et al. 2004). The Kuwajima Formation is stratigraphically correlated with the Okurodani Formation (Maeda 1952) distributed in the Shokawa district, Takayama City (former Shokawa Village), Gifu Prefecture, central Japan (Maeda 1961b). From the tuff beds of the Okurodani Formation, Kusuhashi et al. (2006) reported zircon U−Pb ages of 132.9 ± 0.9 (2 SE) Ma and 117.5 ± 0.7 (2 SE) Ma, and concluded that the formation is correlated to the Barremian to Aptian. Section at Kaseki-Kabe is assigned to the uppermost part of the Kuwajima Formation (Isaji et al., 2005).

• group of beds-level stratigraphic resolution

Environment/lithology: lacustrine - small; lithified siliciclastic sediments

• Itoshiro Subgroup consists mostly of non-marine sediments. The Kuwajima Sandstone and Shale alteration is intercalated with rich plant and fresh-water molluscan beds, from which the insect fossils were found at Kuwajima. Environments include peat marsh, shallow lake, and vegetated swamp. Deposited in intra-arc basin.

Size class: macrofossils

Preservation: mold/impression

Collected by H. Matsuo, I. Fujiyama in 1975-1977

• Repository: National Science Museum, Tokyo

Primary reference: I. Fujiyama. 1978. Some fossil insects from the Tedori Group (Upper Jurassic-Lower Cretaceous), Japan. Bulletin of the National Science Museum, Series C, Geology & Paleontology 4:181-192 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 152995: authorized by Matthew Clapham, entered by Marko Manojlovic on 04.12.2013, edited by Matthew Clapham

Creative Commons license: CC BY (attribution)

Taxonomic list

Insecta
 Hemiptera - Mimarachnidae
"Fulgoridium matsuoi n. sp." = Nipponoridium matsuoi
"Fulgoridium matsuoi n. sp." = Nipponoridium matsuoi Fujiyama 1978 planthopper
NSM-PA12005
 Orthoptera - Prophalangopsidae
Nipponohagla kaga n. gen. n. sp.
Nipponohagla kaga n. gen. n. sp. Fujiyama 1978 hump-winged cricket
NSM-PA12002 (forewing) and 12003 (hindwing) thought to come from same specimen
 Neuroptera - Psychopsidae
"Kagapsychops aranea n. gen. n. sp." = Kagapsychops araneus
"Kagapsychops aranea n. gen. n. sp." = Kagapsychops araneus Fujiyama 1978 silky lacewing
NSM-PA12004