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- New data on the palynology of the Triassic–Jurassic boundary of the Silves Group, Lusitanian Basin, PortugalPublication . Vilas Boas, Margarida; Pereira, Zélia; Cirilli, Simonetta; Duarte, Luís Vítor; Fernandes, PauloNew evidence is presented on the Triassic–Jurassic boundary in the northern Lusitanian Basin, Portugal, based onmiospore assemblages from a composite Upper Triassic to Lower Jurassic succession of the Silves Group. The lat-ter comprises, from base to top, the Conraria, Penela, Castelo Viegas and the Pereiros formations. Three informalpalynologicalzones havebeendocumented andcomparedwith coevalpalynozonesfromWestandSouth Europeprovidingnew biostratigraphic data to detail the age of the lower and upper formationsofthe SilvesGroup and toreview previous age attribution.A Norian, possibly earliest Rhaetian age, is documented for the Conraria Formation on the basis of a palynologicalassemblage referable to theClassopollis meyerianus–Granuloperculatipollis rudis(CG) zone. The Penela andCastelo Viegas formations did not allow a palynostratigraphic revision, due to the not promising lithology for pal-ynological studies. The Pereiros Formation is dated on the basis of microflora assemblages referable, from bottomto top, theIschyosporites variegatus–Kraeuselisporites reissingeri(IK) zone of late Rhaetian–earliest Hettangian ageandPinuspollenites minimus(Pm) zone of Hettangian age. The discontinuity between the underlying CasteloViegas Formation and the overlying Pereiros Formation did not allow to define the lower boundary of the IKpalynozone. The Triassic–Jurassic boundary lies in the lower part of Pereiros Formation within the IK zone. Themicroflora assemblages from the Lusitanian Basin show close affinity to those of eastern N America and westernTethys areas.