Where: Paraná, Brazil (23.3° S, 50.1° W: paleocoordinates 40.8° S, 20.6° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Rio do Rasto Formation, Capitanian to Capitanian (264.3 - 254.2 Ma)

• Presence of Palaeomutela platinensis suggests a position in the upper Serrinha or Morro Pelado Member of the Rio do Rasto Formation (Guerrini et al., 2019). From near the transition from Serrinha Member to Morro Pelado Member. In the basal interval of the Rio do Rasto Formation, the Terraia curvata assemblage correlates with those of the Gai-As Formation, in the Huab Basin, Namibia, Africa (David et al. 2011; Simões et al. 2015). In this unit, just above the last occurrences of bivalves, there are volcanic tufs, and radiometric dating of zircon minerals from them yields ages of 265+2.5 Ma, nearly at the Wordian–Capitanian limit, Guadalupian Epoch (Stollhofen et al. 2000). Therefore, the studied assemblages containing Palaeomutela and other endemic bivalves of the Paraná Basin, which are stratigraphically above bivalves of the Terraia curvata assemblage, are probably Capitanian–Wuchiapingian in age. This assumption is in good accord with very recent U–Pb zircon ages acquired using a sensitive high-resolution ion microprobe and an isotope dissolution thermal ionization mass spectrometer (see Rocha Campos et al. 2019) from tuffs, which suggest that the studied interval of the Rio do Rasto Formation was deposited between the Capitanian and Wuchiapingian stages.

• group of beds-level stratigraphic resolution

Environment/lithology: lacustrine - large; shale

Size class: macrofossils

Preservation: mold/impression

Collected by Alberto Erichsen; reposited in the SM

• Sent to Reed by Dr. Euzebio de Oliveira

Primary reference: F. R. C. Reed. 1935. Some Triassic lamellibranchs from Brazil and Paraguay. Geological Magazine 72:33-42 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 209020: authorized by Matthew Clapham, entered by Matthew Clapham on 23.04.2020

Creative Commons license: CC BY (attribution)