The Lagunitas Formation is a geologic formation in Cuba. The open marine, fluvio-deltaic and lagoonal claystones, limestones and conglomerates preserve fossils dating back to the Early Miocene period. Among others, the fossil primate Paralouatta marianae, the largest primate of the Miocene New World, was found in the formation. Based on microfossils, the age has been determined as Burdigalian.