Where: Japan (43.0° N, 144.4° E: paleocoordinates 44.8° N, 141.7° E)
• coordinate based on nearby landmark
• local area-level geographic resolution
When: Shitakara Formation (Urahoro Group), Early/Lower Oligocene (33.9 - 28.4 Ma)
• STRATIGRAPHIC RELATIONS: From middle of the Urahoro Group, lying between the Yubetsu Fm (Early Oligocene) and the Shakubetsu Formation, also of the Urahoro Group (presumably also Early Oligocene). THICKNESS: Unknown thickness of unit. AGE: Presumably Early Oligocene; from near base of Oligocene in region. STRATIGRAPHIC POSITION: Collection representative of entire formation in local area.
• formation-level stratigraphic resolution
Environment/lithology: marginal marine; lithified, fine-grained, pebbly, gray, conglomeratic, carbonaceous sandstone
Size class: macrofossils
Collection methods: COLLECTOR: Unknown collected, possibly Y. Honda. REPOSITORY: Unknown repository.
Primary reference: Y. Honda. 1986. A Paleogene molluscan fauna from Hokkaido, northern Japan. Paleontological Society of Japan Special Papers 29:3-15 [A. Hendy/A. Hendy]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 68894: authorized by Austin Hendy, entered by Austin Hendy on 12.02.2007
Creative Commons license: CC BY (attribution)
Taxonomic list
unclassified | |
Thecostraca | |
Balanus sp. Da Costa 1778 barnacle | |
Scaphopoda | |
Dentalium sp. Linnaeus 1758 tusk shell
Dentalium (Fissidentalium) nunomae tusk shell | |
Bivalvia | |
Portlandia (Portlandiella) watasei, "Yoldia (Yoldia) laudabilis" = Portlandia laudabilis
"Yoldia (Yoldia) laudabilis" = Portlandia laudabilis Yokoyama 1924 clam | |
Mytilus sp. Linnaeus 1758 mussel
Mytilus mabuchii Oyama and Mizuno 1958 mussel | |
Crenella (Megacrenella) "n. sp. A" Brown 1827 clam | |
Ostrea eorivularis Oyama and Mizuno 1958 oyster | |
Chlamys shitakaraensis Honda 1980 scallop | |
Cyclocardia sp. Conrad 1867 clam | |
Thracia (Thracia) "n. sp." Blainville 1824 clam | |
Solen "n. sp." Linnaeus 1758 clam | |
Mya (? Arenomya) grewingki Makiyama 1934 softshell clam INCLUDES: M. (A.) grewingki grewingki and grewingki kusiroensis
| |
Macoma sp. Leach 1819 tellin clam
Macoma (Macoma) sejugata tellin clam | |
Nemocardium sp. Meek 1876 cockle | |
Hubertschenckia ezoensis Yokoyama 1890 clam | |
Callista sp. Poli 1791 venus clam | |
Mactra sp. Linnaeus 1767 clam
Spisula sp. Gray 1837 clam
Spisula (Mactromeris) sorachiensis Otatsume 1933 clam | |
Corbicula sp. Megerle 1811 clam
"Geloina cf. takaoi" = Polymesoda (Geloina) clam | |
Conchocele bisecta Conrad 1849 clam | |
Gastropoda | |
Naticidae indet. Guilding 1834 moon snail
Neverita (Neverita) sp. Risso 1826 moon snail
Neverita (Neverita) asagaiensis Makiyama 1934 moon snail | |
Colus sp. Röding 1798 true whelk
Neptunea modestoidea Takeda 1953 true whelk | |
Crepidula sp. Lamarck 1799 slipper shell | |
Turritella sp. Lamarck 1799 turret shell | |
Bryozoa | |
Bryozoa indet. Ehrenberg 1831 |