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Tenrecs (Tenrecoidea) and goldenmoles (Chrysochloroidea) are among themost enigmatic mammals alive today. Molecular data strongly support their inclusion in the morphologically diverse clade Afrotheria, and suggest that the two lineages split near the K−T boundary, but the only undoubted fossil representatives of each superfamily are from early Miocene (~20 Ma) deposits in East Africa. A recent analysis of partial mandibles and maxillae ofEochrysochloris, Jawharia, andWidanelfarasia, from the latest Eocene and earliest Oligocene of Egypt, led to the suggestion that the derived “zalambdomorph” molar occlusal pattern (i.e., extreme reduction or loss of upper molar metacones and lower molar talonids) seen in tenrecoids and chrysochloroids evolved independently in the two lineages, and that tenrecoids might be derived from a dilambdomorph group of “insectivoran−grade” placentals that includes forms such asWidanelfarasia. Here I describe the oldest afrosoricid from the Fayum region, ~37MaDilambdogale gheerbranti gen. et sp. nov., and the youngest, ~30 MaQatranilestes oligocaenus gen. et sp. nov.Dilambdogaleis the most generalized of the Fayum afrosoricids, exhibiting relatively broad and well−developed molar talonids and a dilambdomorph arrangement of the buccal crests on the uppermolars, whereasQatranilestesis themost derived in showing relatively extreme reduction of molar talonids. These occurrences are consistent with a scenario in which features of the zalambdomorph occlusal complex were acquired independently and gradually through the later Paleogene. Phylogenetic analysis placesDilambdogaleandWidanelfarasiaas sister taxa to the exclusion of crown afrosoricids, but derived features that these taxa share with early MioceneProtenrechint at the possibility that both taxa might be stem tenrecoids. Late PaleoceneTodralestesandAfrodonfrom Morocco are similarly placed as stem afrosoricids, indicating that African adapisoriculids (includingGaratherium) might also be relevant to the origin of the tenrecoid and chrysochloroid clades.

Key words: Mammalia, Adapisoriculidae, Tenrecidae,Garatherium, Widanelfarasia, Eocene, Oligocene, Egypt.

Erik R. Seiffert [erik.seiffert@stonybrook.edu], Department of Anatomical Sciences, Stony Brook University, Stony Brook, New York, 11794-8081, USA.

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