Abstract
Spores of pteridophytes and bryophytes, and pollen of gymno‐sperms and an angiosperm are described from nine outcrop samples from the Lefipán Formation, Barranca de los Perros, in the Chubut Province of southern Argentina. The material was collected from a section in the lower part of the Lefipán Formation that contains a marine fauna of Maastrichtian age. Twenty‐eight species of trilete and monolete spores, seven gymnosperm pollen species (saccate, colpate and plicate types), and one sulcate (Monosulcites) angiosperm(?) pollen species are described. One new spore species, Rugulatisporites chubutensis n.sp., is proposed. The samples also contain a varied angiosperm flora, in addition to fungal spores, algae (Botryococcus), and rare dinoflagellate cysts.