The Upper Carboniferous~arly Permian stratigraphic succession of the Pyrenees is represented by the volcanic-volcanoclastic deposits of the Grey Unit (GU), followed by the fluvial and lacustrine deposits of the Transition Unit and the l ower Red Unit (Gisbert, 1981). The present work shows new palynological data from the GU. The GU is defined primarily on its lithological characteristics and partly on paleobotanical contents.This unit shows polygenic slope breccias at the base, volcanic and volcanoclastic rocks and deposits of fluvial and lacustrine origin in the upper-middle part and, in the highest part, sandstones and conglomerates that characterise the apical part of alluvial tan bodies. GU corresponds to the Aguiró Formation and to the Erillcastell Formation described by Dalloni (1930), Mey et al. (1968), and Nagtegaal {1969) in a more westerly area. Small floral assemblages of Autunian age have been recorded {Dalloni, 1930; Nagtegaal, 1969; Sroutin and Gisbert, 1985; Talens and Wagner, 1995; Wagner and Álvarez-Vázquez, 2010). Unfortunately, none of them shows apalynological assemblage. Recently, Pereira et al. {2014) published a new U-Pb SHRIMP dating of zircons that endose the Grey Unit age to 307.4+·1.4Ma ·298.6+-2.5 M a. (Upper Carboniferous). A sample with palynological content was obtained at the base of Río Pallarols Section {Argestues, Lleida, Spain) and is composed by: AconthatriletestenuispinosusNaumova, Apiculotisparisporvispinasus{Leschik) Schulz, ColamasparabreviradiotoKosanke, Colomosparomicrorugasa (lbrahim) Schopf, Wilson and Sentall, CalamasporapedatoKosanke, CyclogronisparitesmicrogranusSharadwaj, Florinites juniarPotonie and Kremp, Flarinitesmediapudens {Loose) Potonie and Kremp, Gronulotisparitesmicrogronifer lbrahim, Granulatisparitesgranulatus lbrahim, LaevigatosporitesperminutusAipern, Loevigotasparites vulgaris (lbrahim) lbrahim, Leiatriletesodnatus {Kosanke) Potonié and Kremp, Laphotriletesmicrosoetasus {Loose) Potonie and Kremp, Lundblodisparagigontea {Aipern) Doubinger, Potanieisporitesnavlcus Shardwaj, Potanieisporites simplex Wilson, Chramotriletes sp., Guthaerlisparites sp., Maculatosparites sp., Nuskoisparites sp., Plicatipallenites sp. and Vestispara sp. The taxonomic composition of the assemblage is characteristic of an "Autunians.l." flora and could be assigned a Stephanian age (Kasimovian-Gzhelian) by comparison with the classic palynostratigraphic scales described for the Carboniferous deposits of Western Europe{Doubinger, 1974; Clayton et al. 1977). This data is consisten! with the radiometric dating carried out at equivalen! levels by Pereira et al. {2014).

Trabajo presentado en el 2nd International congress on Permian and Triassic, celebrado en Casablanca (Marruecos), del 25 al 27 de abril de 2018

Peer reviewed