Than-u-daw, Pondaung Sandstone (Eocene of Myanmar)

Also known as Than-udaw AMNH A8

Where: Myanmar (21.7° N, 94.8° E: paleocoordinates 13.1° N, 93.3° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Pondaung Formation, Bartonian (41.3 - 38.0 Ma)

• The whole sequence of units was originally defined as the ‘Pondaung Sandstones’ by Cotter (1914), but the horizon yielding Eocene vertebrate fossils is now known as the ‘Upper Member’ of the Pondaung Formation (see Maung et al. 2005). The most recent age for this unit is ~39–38 Ma and so it can be regarded as middle Bartonian (see Tsubamoto et al. 2011).

• formation-level stratigraphic resolution

Environment/lithology: terrestrial; brown, yellow sandstone and red, white, yellow siliciclastic

• successive beds of cherry-red, bright buff and cream-white earths interstratified with brown or buff sandstones

Size class: macrofossils

Reposited in the AMNH

• collected by H. M. Lahiri, specimens housed in the Geological Museum, Calcutta and AMNH

•Colbert's list has both Pondaung and Upper Irrawaddy associated with the fossils he reports, but it's not clear what that means

Primary reference: G. E. Pilgrim and G. P. Cotter. 1916. Some newly discovered Eocene mammals from Burma. Records of the Geological Survey of India 47:42-77 [J. Alroy/E. Leckey/E. Leckey]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 41180: authorized by John Alroy, entered by Erin Leckey on 07.07.2004, edited by Philip Mannion and Bethany Allen

Creative Commons license: CC BY (attribution)

Taxonomic list

Polypodiopsida
  -
"Acrocarpoxylon siwalicus" = Acrocarpus siwalicus3
"Acrocarpoxylon siwalicus" = Acrocarpus siwalicus3 Yadav 1989
MNHN.F.40109
Angiospermae
 Fabales - Fabaceae
Cynometroxylon holdenii3 Gupta 1935 legume
MNHN.F.40130
 Rosids - Moraceae
Ficoxylon mogaungense3 Licht et al. 2014 mulberry
MNHN.F.40128, MNHN.F.40129
Mammalia
 Artiodactyla - Helohyidae
Pakkokuhyus lahirii n. gen.2 Pilgrim 1928 even-toed ungulate
right mandibular ramus containting the molar dentition
 Artiodactyla - Archaeomerycidae
Irrawadymeryx pondaungi n. gen. n. sp.4
Irrawadymeryx pondaungi n. gen. n. sp.4 Métais et al. 2007 ruminant
TUDW-20061 - holotype
 Artiodactyla - Anthracotheriidae
Anthracotheriidae indet.5, "Anthracothema pangan" = Anthracotherium pangan5, "Anthracothema rubricae" = Anthracotherium pangan5, "Anthracokeryx myaingensis n. sp." = Anthracokeryx tenuis5
Anthracotheriidae indet.5 Leidy 1869 anthracothere
fragmentary left mandibular ramus
"Anthracothema pangan" = Anthracotherium pangan5 Pilgrim and Cotter 1916 anthracothere
portion of a right maxilla with three molars, and some molars from the left side of the same palate as well as a part of the symphyseal region
"Anthracothema rubricae" = Anthracotherium pangan5 Pilgrim and Cotter 1916 anthracothere
right mandibular ramus
"Anthracokeryx myaingensis n. sp." = Anthracokeryx tenuis5 Pilgrim and Cotter 1916 anthracothere
isolated teeth
 Perissodactyla - Amynodontidae
Paramynodon birmanicus1 odd-toed ungulate