ABStrAct: New palynomorph data from the Paraná Basin, south Brazil, suggests a discontinuous sedimentation during the Lower Devonian. A comparison is made with coeval beds in Argentina, Bolivia and other intracratonic basins from Brazil. The Lochkovian/Pragian boundary is best developed in Bolivia and is distinguished by the first appearance of Ramochitina magnifica Lange 1967, which succeeds characteristic late Lochkovian chitinozoan species from underlying strata (e.g. Angochitina filosa Eisenack 1959, Cingulochitina ervensis Paris 1979, Cingulochitina serrata Taugourdeau and Jekhowsky 1960, Ramochitina jutaiense Grahn et al. 2003, and Urochitina loboi Volkheimer et al. 1986). Based on spore evidence, the Urochitina loboi Zone is considered as a subzone in the upper late Lochkovian part of the Angochitina strigosa Zone. A palynomorphic barren interval, corresponding to most of the Pragian (PoW, pre-Su spore Interval Zone of Streel et al. 1987), occurs in Western Gondwana. No positive evidence is present for rocks coeval with the Emsian AB and FD spore Oppel Zones of Streel et al. (1987). Ancyrochitina biconstricta (Lange 1949) is a characteristic Emsian species, and not conspecific with Cladochitina biconstricta Lange 1949 sensu Quadros 1982, which is a new late Eifelian – late early Givetian species. Ramochitina praemagnifica and Spinachitina aciculata, are described as new species.
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