Ban Sa (Miocene to of Thailand)

Also known as Chiang Muan Basin

Where: Thailand (18.9° N, 100.3° E: paleocoordinates 17.6° N, 99.9° E)

• coordinate based on nearby landmark

When: MN 7 + 8 to MN 7 + 8 (12.8 - 9.7 Ma)

• "Middle Miocene": upper and middle lignite seams are in a normal polarity zone correlated with anything between chron C5ABn and chron C5n, but equivalent to "the top of... MN 8 and the base of MN 9" according to Pickford et al. 2004

• member-level stratigraphic resolution

Environment/lithology: mire or swamp; lignite and mudstone

• "Paleosols indicate some climatic seasonality... vegetation corresponded to a mosaic of freshwater swamps [presumably yielding the lignites], with a Syzygium-dominated lowland forest"
• "The sediments consist mainly of mudstones and sandstones incalated with paleosols and several lignite beds [yielding the fossils]"; section shows a long interval of "purple mudstones" separating the lower and middle plus upper lignite seams, with the latter separated by "purple mudstones" and "sandy clays"

Size class: macrofossils

Collection methods: specimens have "TF" museum numbers and clearly derive from different collections than the "CMu" material collected by the Japan-Thailand Paleontology Expedition from the Chiang Muan Basin

Primary reference: Y. Chaimanee, D. Jolly, M. Benammi, P. Tafforeau, D. Duzer, I. Moussa, and J.-J. Jaeger. 2003. A Middle Miocene hominoid from Thailand and orangutan origins. Nature 422:61-65 [J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 71580: authorized by John Alroy, entered by John Alroy on 29.04.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• hominid specimens are from the middle and upper lignite seams in the section, but some mammal fossils are from the lower lignite seam and carbonaceous shales below it
Show authors, comments, and common names
Mammalia
 Proboscidea - Stegodontidae
Stegodontidae indet.
Stegodontidae indet. Osborn 1918 proboscidean
"stegolophodont mastodon"
 Artiodactyla - Suidae
Hyotherium cf. pilgrimi
 Artiodactyla - Tragulidae
Siamotragulus sp., Dorcatherium sp.
Siamotragulus sp. Thomas et al. 1990 chevrotain
Dorcatherium sp. Kaup 1839 chevrotain
 Artiodactyla - Bovidae
Eotragus sp.
Eotragus sp. Pilgrim 1939 antelope