Where: Azerbaijan (39.6° N, 45.1° E: paleocoordinates 8.5° S, 41.3° E)
• coordinate based on nearby landmark
• small collection-level geographic resolution
When: Arpa Formation, Wordian (266.9 - 264.3 Ma)
• Basal unit of the Midian stage of the Tethyan timescale. Kotlyar et al. (1989) identified two fusulinid zones, the lower Yangchienia thompsoni and the upper Chusenella abichi. In central Iran, Chusenella abichi occurs with Neoschwagerina margaritae (Leven, 1998), suggesting a Wordian age for the entire Arpa Formation.
• group of beds-level stratigraphic resolution
Environment/lithology: lithified, fine-grained, gray, cherty/siliceous limestone
Size class: macrofossils
Primary reference: G. V. Kotlyar, Y.u. D. Zakharov, G. S. Kropatcheva, G. P. Pronina, I. O. Chedija and V. I. Burago. 1989. Evolution of the latest Permian biota: Midian regional stage in the USSR 1-184 [M. Clapham/M. Clapham]more details
Purpose of describing collection: biostratigraphic analysis
PaleoDB collection 94933: authorized by Matthew Clapham, entered by Matthew Clapham on 01.04.2010
Creative Commons license: CC BY (attribution)
Taxonomic list
Anthozoa | |
Polythecalis ex gr. yangtzeensis, Polythecalis ex gr. variabilis, Wentzellophyllum (Armeniaphyllum) densicolumnatum
Polythecalis ex gr. yangtzeensis Huang 1932 horn coral
Polythecalis ex gr. variabilis Gerth 1938 horn coral | |
Rhynchonellata | |
Septospirigerella baissalensis Grunt 1965 | |
Strophomenata | |
"Krotovia jisuensiformis" = Echinauriella jisuensiformis, Ogbinia dzhagrensis
"Krotovia jisuensiformis" = Echinauriella jisuensiformis Sarycheva 1965
Ogbinia dzhagrensis Sarycheva 1965 | |
Marginifera magniplicata Huang 1932 | |
Foraminifera | |
Pachyphloia aff. ovata Lange 1925 | |
Sumatrina sp. Volz 1904 | |
Verbeekina sp. Staff 1909 | |
Chusenella tumefacta, Chusenella cf. referta, Rugosofusulina sp., Pseudofusulina ex gr. parachihsiaensis
Rugosofusulina sp. Rauser-Chernousova 1937 | |
Globivalvulina "sp. 2" Schubert 1921 | |