Biretia
The first discovery of Biretia was a single tooth dated to approximately 37 mya, which was found in 1988 at the Bir el Ater site in Algeria.Both were discovered at Birket Qarun Locality 2 (BQ-2), which is located about 60 mi south of Cairo in Egypt's Fayum depression.Biretia is unique among early anthropoids in exhibiting evidence for nocturnality, but derived dental features shared with younger parapithecids draw this genus, and possibly 45-million-year-old Algeripithecus (Strepsirrhini), into a morphologically and behaviorally diverse parapithecoid clade of great antiquity.We can infer the possibility of a nocturnal lifestyle for B. megalopsis' from the animal's molar roots, which are truncated to accommodate for large eye sockets typical of a nocturnal primate.The large eye structure and similarity to the modern tarsiers also suggests that it has lost its tapetum lucidum.