New Phiomorpha and Anomaluridae from the Late Eocene of North-West Africa: Phylogenetic Implications

Abstract

Until recently, the ancient fossil family Phiomyidae (suborder Hystricognathi) was recorded only from the early Oligocene site of the Fayum, Egypt (Andrews, 1906; Osborn, 1908; Schlosser, 1910, 1911; Wood, 1968). As defined by Lavocat (1973), the infraorder Phiomorpha includes many other representatives that occurred in the middle or late Oligocene of the Balearic islands (Adrover and Hugueney, 1975; Adrover et al., 1978), in the Miocene of Africa (Stromer, 1926; Lavocat, 1973), of India and Pakistan (Black, 1972; Flynn and Jacobs, 1982; Flynn et al., 1983; Jaeger et al., 1980), and of the eastern Mediterranean (Chios, Greece) (Tobien, 1968). Phiomorphs are still represented in Africa by two living families: the Thryonomyidae and Petromyidae (or Petromuridae). At the Fayum site, Wood (1968) described five new genera and nine species of phiomyids, showing a great variety of dental patterns (three to six crests in upper and lower molars, for example), but possessing already in the Oligocene all the characteristics of the modern representatives of the thryonomyoids: retention of dP4/4; hystricomorphy; hystricognathy; and multiserial enamel on the incisors.