Fukami River bank and floor, Ajimu-machi, Usa City (Pliocene of Japan)

Also known as Upstream of Shiromaru-bashi Bridge; Ajimu fauna; Oita Prefecture

Where: Kyushu, Japan (33.4° N, 131.3° E: paleocoordinates 33.9° N, 130.7° E)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Tsubusagawa Formation, Late/Upper Pliocene (3.6 - 2.6 Ma)

• Lowermost part of the middle Tsubusagawa Formation

•

•Iijima et al. 2016: Although some age estimates and their stratigraphic levels are inconsistent, the age of the alligator fossil bearing horizon is most likely at ~3.0 Ma in the Late Pliocene.

• bed-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; sandstone

• Iijima et al. 2016: All the crocodylian materials described here were recovered from very fine sandstone (Matsuoka, 2001) of the lowermost part of the middle Tsubusagawa Formation, which crops out at the Fukami River bank and floor, upstream of Shiromaru-bashi Bridge, Ajimu-machi, Usa City, Oita Prefecture (Fig. 2).

Size class: macrofossils

Collected in 1990's

Primary reference: M. Iijima, K. Takahashi, and Y. Kobayashi. 2016. The oldest record of Alligator sinensis from the Late Pliocene of Western Japan, and its biogeographic implication. Journal of Asian Earth Sciences 124:94-101 [P. Mannion/P. Mannion]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 180691: authorized by Philip Mannion, entered by Philip Mannion on 28.07.2016

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Reptilia
 Crocodylia - Alligatoridae
Alligator sinensis, cf. Alligator sinensis
Alligator sinensis Fauvel 1879 Chinese alligator
left quadrate (LBM 0142000027), left dentary (LBM 0142000753), left angular (LBM 0142000754), left articular (LBM 0142000756)
cf. Alligator sinensis Fauvel 1879 Chinese alligator
left jugal (LBM 0142000054), isolated teeth (LBM 0142000020; LBM 0142000023; LBM 0142000036; LBM 0142000039; LBM 0142000042; LBM 0142000044; LBM 0142000047; LBM 0142000049; LBM 0142000050), right ilium (LBM 0142000025), osteoderms (LBM 0142000030; LBM 0142000032; LBM 0142000035; LBM 0142000043; LBM 0142000046; LBM 0142000051)