M Shell Bed (Triassic to of China)

Where: Guizhou, China (26.3° N, 106.7° E: paleocoordinates 13.3° N, 95.1° E)

• coordinate stated in text

• small collection-level geographic resolution

When: Yingshangpo Member (Qingyan Formation), Middle Triassic to Middle Triassic (247.2 - 242.0 Ma)

• The Middle Triassic succession at Qingyan is lithologically divided into the Qingyan and Guiyang Formations. The Qingyan Formation is an 890 m-thick succession composed of five members: Xiaoshan, Mafengpo, Yingshangpo, Leidapo and Yuqing Members in ascending order. The Xiaoshan Member is dominated by grey medium- bedded limestone; the Mafengpo Member consists of dark mudstone; the Yingshangpo Member is composed of grey medium-bedded bioclastic limestone interbedded with black shale; and the Leidapo Member is characterized by black mudstone in the lower part and calcareous mudstone in the upper part.

• group of beds-level stratigraphic resolution

Environment/lithology: intrashelf or intraplatform reef; lithified, gray wackestone and lithified, black packstone

• Qingyan was situated on a shallow carbonate bank, the junction between the carbonate platform in the north and west and a deep basin in the south and east during the Early and Middle Triassic times
• the Yingshangpo Member is composed of grey medium-bedded bioclastic limestone interbedded with black shale. Brachiopod skeletal packstone-wackestone.

Size class: macrofossils

Collection methods: surface (in situ), mechanical,

• Brachiopod specimens statistically studied in this paper were obtained from one shell slab, 45 cm x 25 cm x 10 cm, of the Yingshangpo Member and another shell slab, 60 cm x 30 cm x 5 cm, of the Leidapo Member at the Qingyan section.

Primary reference: J. Chen, Z. Chen, and J. Tong. 2010. Palaeoecology and taphonomy of two brachiopod shell beds from the Anisian (Middle Triassic) of Guizhou, Southwest China: Recovery of benthic communities from the end-Permian. Global and Planetary Change 73:149-160 [N. Bonuso/N. Bonuso]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 111833: authorized by Nicole Bonuso, entered by Nicole Bonuso on 29.06.2011

Creative Commons license: CC BY (attribution)

Taxonomic list

Rhynchonellata
 Spiriferinida - Mentzeliidae
Mentzelia mentzeli Dunker 1851
Madoia sp. Sun and Ye 1982
 Spiriferinida - Sinucostidae
Sinucosta sp. Dagys 1963
 Spiriferinida - Spiriferellinidae
 Rhynchonellida - Erymnariidae
 Rhynchonellida - Cyclothyrididae
"Septaliphoria sinensis" = Costirhynchopsis sinensis
"Septaliphoria sinensis" = Costirhynchopsis sinensis Yang and Xu 1966
 Rhynchonellida - Norellidae
 Terebratulida - Angustothyrididae
"Rhaetina angustaeformis" = Angustothyris angustaeformis
"Rhaetina angustaeformis" = Angustothyris angustaeformis Boekh 1872
 Terebratulida - Zeilleriidae
"Aulacothyris angustaeformis" = Sacothyris angustaeformis
"Aulacothyris angustaeformis" = Sacothyris angustaeformis Yang and Xu 1966