A taxonomic revision of the Tribe Aequipectini from the upper Burdigalian, Lower Miocene Pirabas Formation in Brazil) resulted in an identification of Leptopecten daideleus comb. nov., Perapecten tetristriatus and description of Iemanjavola monlafertei gen. et sp. nov. The genus Perapecten is re-validated, P. tetristriatus being the first fossil representative of the genus, extending it back to the Early Miocene of the western Atlantic Ocean and Middle Miocene–Pliocene Perapecten scabrellus from the Mediterranean Sea/Central Paratethys is included into Perapecten. We also reported the oldest record of Leptopecten, which along with Perapecten, seem to have originated in the Early Miocene tropical region of the western Atlantic Ocean. Leptopecten dispersed during the Middle or Late Miocene to the eastern Pacific through the Central American Seaway, while Perapecten spread across the North Atlantic into Europe via the Circumtropical Current and the Gulf Stream/North Atlantic Drift.

Key words: Bivalvia, Pectinidae, Leptopecten, Perapecten, Iemanjavola , Central American Seaway, ocean currents, Miocene, Pirabas Formation, Brazil.

María Belén Santelli [mbsantelli@gmail.com; ORCID:  https://orcid.org/0000-0003-3077-4384] and Claudia J. del Río [claudiajdelrio@gmail.com; ORCID: https://orcid.org/0000-0001-5167-9656 ], División Paleoeinvertebrados, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (MACN-CONICET), Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina. Vladimir de Araújo Távora [vladimir@ufpa.br; ORCID: https://orcid.org/0000-0001-5053-1422 ], Instituto de Geo-ciências (IG), Universidade Federal do Pará (UFPA), Av. Augusto Correa 01, Caixa Postal 1611, CEP 66075-110 Belém, Pará, Brasil. Maria Inês Feijó Ramos [mramos@museu-goeldi.br; ORCID: https://orcid.org/0000-0003-0276-0575 ], Museu Para-ense Emílio Goeldi (MPEG), Av. Perimetral 1901, CEP 66077-830 Belém, Pará, Brasil.