Na Duong Mine level 11 (Eocene to of Vietnam)

Where: Lang Son, Vietnam (21.8° N, 106.1° E: paleocoordinates 21.6° N, 105.0° E)

• coordinate stated in text

When: Rhin Chua Formation, Bartonian to Bartonian (41.3 - 33.9 Ma)

• characterized as "late Middle to Late Eocene"

Environment/lithology: lacustrine - large; claystone

• characterized as deep lake
• The sediments of the Rhin Chua Formation consist predominantly of marly claystones. Thin beds of fine-grained sandstone with symmetric ripple marks occur in the upper part of the section (Fig. 3F). Weathering turns the brownish colour of the fresh claystones into reddish to purple colours, indicating the secondary formation of haematite. Weathered outcrops show a cyclic occurrence of more solid horizons at intervals of ~ 0.5 m. Frequently, the claystones are bioturbated, in particular near the base and top of the succession (Fig. 3E). These bioturbated

•parts of the profile contain abundant fossil remains of benthic (mollusk shells) and nektonic fauna (cyprinid fish teeth).

Size classes: macrofossils, mesofossils

Collection methods: salvage, quarrying, sieve,

Primary reference: M. Böhme, M. Aiglstorfer, P.-O. Antoine, E. Appel, P. Havlik, G. Métais, Laq The Phuc, S. Schneider, F. Setzer, R. Tappert, Dang Ngoc Tran and D. J. Uhl Prieto. 2013. Na Duong (northern Vietnam) – an exceptional window into Eocene ecosystems from Southeast Asia. Zitteliana A 53:120-167 [P. Holroyd/P. Holroyd/M. Carrano]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 169422: authorized by Patricia Holroyd, entered by Patricia Holroyd on 25.05.2015

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
unclassified
  -
Cristaria mothanica
Actinopteri
 Cypriniformes - Cyprinidae
Xenocyprinae indet., Cultrinae indet., Barbinae indet., Planktophaga minuta n. gen. n. sp., "? Acheilognathidae indet." = Acheilognathinae
Xenocyprinae indet. carp-like fish
Cultrinae indet. carp-like fish
Barbinae indet. carp-like fish
Planktophaga minuta n. gen. n. sp. Böhme et al. 2013 carp-like fish
"? Acheilognathidae indet." = Acheilognathinae carp-like fish
Gastropoda
 Architaenioglossa - Viviparidae
Viviparidae indet.
Viviparidae indet. Gray 1847 snail
 Cerithioidea - Thiaridae
? Tarebia indet.
? Tarebia indet. Adams and Adams 1854 snail
Bivalvia
 Unionida - Unionidae
Unionidae indet., Cuneopsis indet.
Unionidae indet. Rafinesque 1820 freshwater mussel
undescribed large alatiform unionid
Cuneopsis indet. Simpson 1900 freshwater mussel