USNM9271, Ko Muk Island northeast undivided (Permian of Thailand)

Where: Trang, Thailand (7.4° N, 99.3° E: paleocoordinates 31.3° S, 107.5° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Rat Buri Formation, Roadian (272.3 - 268.8 Ma)

• Blocks are derived from seacliffs, making it impossible to measure a stratigraphic section or determine whether they are derived from a single horizon. The age of the Rat Buri fauna is problematic. "Rat Buri" limestones likely range in age from Kungurian through Capitanian to perhaps Wuchiapingian. Wordian fusulinids appear most common in other collections, but are not found in association with the brachiopod localities. The brachopod fauna is most similar to the Wordian Amb Formation of the Salt Range, in Pakistan, tentatively indicating a Wordian age.

• group of beds-level stratigraphic resolution

Environment/lithology: offshore shelf; argillaceous, sandy limestone

• Interpreted as rather quiet water that was deep enough not to be disrupted by ordinary wave action. It was a fairly flat sea floor bearing an abundant fauna of small organisms with bryozoans and crinoids in patches like gardens.

Size class: macrofossils

Preservation: replaced with silica

Collection methods: bulk, surface (float), chemical,

Primary reference: R. E. Grant. 1976. Permian brachiopods from southern Thailand. Paleontological Society Memoir 9:1-269 [D. Bottjer/M. Clapham/M. Clapham]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 40870: authorized by David Bottjer, entered by Matthew Clapham on 02.07.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Concentrates on brachiopods, and other groups are listed only in the text for the generic total collection, not for the subset individual blocks. Total includes 96 specimens that were collected separately from the 10 blocks and therefore does not exactly equal the sum of subset blocks.
Crinoidea
  -
Crinoidea indet. Miller 1821 Sea lily
Abundant ossicles
 Dendrocrinida - Apographiocrinidae
Apographiocrinus komukensis n. sp. Webster and Jell 1993 Sea lily
 Dendrocrinida - Graphiocrinidae
Contocrinus andamanensis n. sp. Webster and Jell 1993 Sea lily
Calyx
 Poteriocrinina - Clathrocrinidae
Clathrocrinidae indet. Strimple and Moore 1971 Sea lily
Blastoidea
  -
Blastoidea indet. Say 1825 blastoid
Gastropoda
 Euomphalina -
Euomphaloidea indet. White 1877 snail
At least one
 Pleurotomariacea -
"Pleurotomariacea indet." = Pleurotomarioidea
"Pleurotomariacea indet." = Pleurotomarioidea Swainson 1840 snail
5 or 6 genera
Bivalvia
 Pectinida -
Pectinoidea indet. Rafinesque 1815 scallop
Rhynchonellata
 Rhynchonellida - Psilocamaridae
Goleomixa acymata Grant 1976
 Rhynchonellida - Wellerellidae
Uncinunellina sp. Grabau 1932
 Spiriferida - Ambocoeliidae
Cruricella couria Grant 1976
 Spiriferida - Spiriferellidae
 Athyridida - Athyrididae
"Composita advena" = Posicomta advena Grant 1976
 Athyridida - Diplospirellidae
Uncinella sp. Waagen 1883
 Athyridida - Neoretziidae
Hustedia ratburiensis Waterhouse and Piyasin 1970
Hustedia funaria Grant 1976
 Spiriferinida - Paraspiriferinidae
 Terebratulida - Dielasmatidae
Dielasma sp. King 1856
 Terebratulida - Notothyrididae
? Notothyris sp. Waagen 1882
Strophomenata
 Strophomenida - Rugosochonetidae
"Chonetinella cymatilis" = Neochonetes (Sommeriella) cymatilis
"Chonetinella cymatilis" = Neochonetes (Sommeriella) cymatilis Grant 1976
 Productida - Cyclacanthariidae
Acritosia sp. Cooper and Grant 1969
 Productida - Rigbyellidae
Rigbyella crassa Grant 1976
 Productida - Lyttoniidae
? Eolyttonia sp. Frederiks 1924
 Productida - Cooperinidae
Ceocypea sp. Grant 1972
Stenolaemata
 Cystoporata - Fistuliporidae
Fistuliporidae indet. Ulrich 1882
Large branching, bifoliate, and encrusting
 Cryptostomida -
Cryptostomida indet. Vine 1884
Bifoliate
 Cryptostomata - Fenestellidae
Fenestellidae indet. King 1850
Coarse and fine mesh varieties
Deuteropoda
  -
Ostracoda indet. Latreille 1802 ostracod
Anthozoa
 Rugosa -
Rugosa indet. horn coral
Small horn coral that lacks any expression of septa within the calice
 Stauriida - Lophophyllidae
Lophophyllidium sp. Grabau 1928 horn coral
 Stauriida - Plerophyllidae
Plerophyllum sp. Hinde 1890 horn coral
Ufimia sp. Shtukenberg 1895 horn coral
 Favositida - Pseudofavositidae
Pseudofavosites sp. Gerth 1922 tabulate coral