Pampatheriidae is a group of South American native cingulates recorded from the Middle Miocene to the Early Holocene. These animals arrived in North America during the Great American Biotic Interchange. During the Quaternary, at least three genera existed: Tonnicinctus Góis, González Ruiz, Scillato-Yané and Soibelzon, Pampatherium Gervais and Ameghino, and Holmesina Simpson. They are differentiated mainly by craniodental and osteodermal characters. In this paper, we describe a new species of Holmesina from Bahia state, Brazil. Two well-preserved specimens possessing osteoderms associated with their skeletons enabled us to determine the genus and species more reliably. Holmesina cryptae sp. nov. differs from the other Quaternary pampatheres by having the simplest ornamental pattern of osteoderms, sharing characteristics between Pampatherium and Holmesina osteoderms and the most robust skull among the Holmesina species, however preserving the main synapomorphies of the genus. Moreover, the integrity of the remains of H. cryptae sp. nov. enabled us to describe elements of the hyoid apparatus, the clavicle, the entire vertebral column and the pelvis. It was also possible to measure its total axial length (2.2 m) more reliably, which is smaller than previously estimated for other pampatheres. Holmesina cryptae sp. nov. constitutes the sixth species of the genus, and it is the fourth in South America. Fil: Moura, Jorge Felipe. Universidade Federal do São Carlos; Brasil Fil: Gois Lima, Flavio. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Galliari, Fernando Carlos. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernandes, Marcelo Adorna. Universidade Federal do São Carlos; Brasil
