First record of Ginkgo-related fertile organs (Hamshawvia, Stachyopitys) and leaves (Baiera, Sphenobaiera) in the Triassic of Brazil, Santa Maria formation

• A new record of ginkgophytes in South Brazil, including vegetative and reproductive structures, is informed.
• The in general complex taxonomic insertion of Ginkgo-related leaves is analysed.
• Taphonomic processes involved in the coating of some leaf impressions by ferric hydroxide are discussed.
• The geological and tectonic control over the deposition is compare with those from other Gondwanic Triassic basins.
• Ginkgophyte related forms in the Triassic of Gondwana are compiled looking to correlations with the Brazilian materials.

This paper describes new ginkgophytes recently discovered in a new exposure of the original type section of the Passo das Tropas Member, Santa Maria Formation, linked to Paraná Basin succession. The well-preserved fossils come from a very fine red laminated mudstone representing a lacustrine interval, within a broader low-sinuosity fluvial succession. The material occurs in a Dicroidium-dominated assemblage and is represented by the leaves Baiera and Sphenobaiera, accompanied by the fertile structures Hamshawvia and Stachyopytis. Cuticle fragments preserved on leaf impressions of Sphenobaiera schenkii show xeromorphic features. The geology, paleogeography and paleoclimate of the Passo das Tropas Member (PTM), Santa Maria Formation, is discussed. By comparing these ginkgophytes with those from other Gondwanan assemblages, the Brazilian deposits earlier assigned to Anisian–Ladinian age can now be extended to the Carnian age.

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