Ainoshima Island (KMNH collection): Rupelian, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Chondrichthyes - Hexanchiformes - Hexanchidae
7 specimens
KMNH VP 100,074-077, 080-082
4 specimens
KMNH VP 100,078, 079, 083, 084
Chondrichthyes - Squatiniformes - Squatinidae
Squatina sp. Dumeril 1806
1 specimen
KMNH VP 100,109
Chondrichthyes - Squaliformes - Squalidae
1 specimen
KMNH VP 100,107
Chondrichthyes - Myliobatiformes - Myliobatidae
Myliobatis sp. Cuvier 1816
1 specimen
KMNH VP 100,111
Chondrichthyes - Lamniformes - Cetorhinidae
Cetorhinus sp. de Blainville 1816
1 specimen
KMNH VP 100,108
Chondrichthyes - Lamniformes - Lamnidae
Isurus desori (Sismonda 1849)
1 specimen
KMNH VP 100,094
Chondrichthyes - Lamniformes - Otodontidae
Yabumoto 1987 4 specimens
KMNH VP 100,092; 100,093; 100,112; 100,116
Chondrichthyes - Lamniformes - Odontaspididae
6 specimens
KMNH VP 100,095-100
Chondrichthyes - Carcharhiniformes - Triakidae
Galeorhinus sp. de Blainville and Prévost 1816
1 specimen
KMNH VP 100,106
Chondrichthyes - Carcharhiniformes - Carcharhinidae
Carcharhinus spp. de Blainville 1816
3 specimens
KMNH VP 100,101-103
Negaprion sp. Whitley 1940
1 specimen
KMNH VP 100,105
Chondrichthyes - Carcharhiniformes - Galeocerdonidae
Galeocerdo sp. Müller and Henle 1837
1 specimen
KMNH VP 100,104
Chondrichthyes - Heterodontiformes - Heterodontidae
Heterodontus sp. de Blainville 1816
5 specimens
KMNH VP 100,085-089
see common names

Geography
Country:Japan
Coordinates: 34.0° North, 130.8° East (view map)
Paleocoordinates:36.5° North, 127.6° East (Wright 2013)
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period: Paleogene Epoch: Oligocene
Stage: Rupelian 10 m.y. bin: Cenozoic 4
Key time interval: Rupelian
Age range of interval: 33.9 - 27.3 m.y. ago
Stratigraphy
Formation:Yamaga
Stratigraphic resolution:group of beds
Stratigraphy comments: The age of the Yamaga Formation in the Ashiya area was placed at 31.7±2.3 Ma (upper Lower Oligocene) based on fission track dating (Ozaki and Hamasaki, 1991). This was supported by further fission track dating and biostratigraphic studies conducted in the upper and lower formations (Tsuchi et al., 1987; Ozaki and Hamasaki, 1991; Okada, 1992). The Ashiya Group is correlated with the calcareous nannofossil Subzone CP19a of Okada and Bukry (1980) (Okada, 1992) and the planktonic foraminiferal Subzone P21a of Berggren and Miller (1988) (Ibaraki, 1994).
Lithology and environment
Primary lithology: "siliciclastic"
Environment:marine indet.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Reason for describing collection:general faunal/floral analysis
Collection method comments: Repository: Kitakyushu Museum of Natural History
Taxonomic list comments:Some material actually from Kaijima Island, but provenance of specimens/taxa are not given so all are included here
Metadata
Database number:278481
Authorizer:M. Clapham Enterer:M. Clapham
Modifier:M. Clapham Research group:vertebrate
Created:2026-03-24 20:08:01 Last modified:2026-03-24 21:02:28
Access level:the public Released:0000-00-00 00:00:00
Creative Commons license:
Reference information

Primary reference:

94415. T. Uyeno, Y. Yabumoto, and N. Kuga. 1984. Fossil fishes of Ashiya Group - 1 - Late Oligocene elasmobranchs from islands of Ainoshima and Kaijima, Kitakyushu. Bulletin of the Kitakyushu Museum of Natural History 5:135-142 [M. Clapham/M. Clapham]

Secondary references:

94412 Y. Yabumoto. 1987. Oligocene lamnid shark of the genus Carcharodon from Kitakyushi, Japan. Bulletin of the Kitakyushu Museum of Natural History 6:239-264 [M. Clapham/M. Clapham]