Bebej et al.—First remingtonocetid archaeocete from Egypt from Egypt
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Figure 5. Left acetabula on innominates of middle Eocene archaeocetes, in lateral view (anterior at left). (1) Rayanistes afer n. gen. n. sp. (CGM 42190); (2) Remingtonocetus domandaensis (GSP-UM 3552); (3) R. domandaensis (GSP-UM 3408); (4) Dalanistes ahmedi (GSP-UM 3106); (5) Ambulocetus natans (H-GSP 18507); (6) Rodhocetus kasranii (GSP-UM 3012). The margin of the lunate surface is outlined on each specimen to demonstrate closure of the acetabular notch separating ends of the lunate surface. The acetabular notch is narrow in Rayanistes afer (1), narrow to closed in other Remingtonocetidae (2–4), and more open in A. natans (5) and protocetids like R. kasranii (6).
Figure 6. Left femora of middle Eocene archaeocetes. (1–2) Rayanistes afer n. gen. n. sp. (CGM 42190), posterior and anterior views; (3) Remingtonocetus domandaensis (GSP-UM 3054), anterior view; (4) Ambulocetus natans (H-GSP 18507), anterior view; (5) Maiacetus inuus (GSP-UM 3551), anterior view; (6) Rodhocetus kasranii (GSP-UM 3012), anterior view. Note the more robust femora of Rayanistes (1–2) and Remingtonocetus (3) compared to those of other archaeocetes, and the more vertically oriented head and shorter neck on the femur of Rayanistes (1–2). Specimens are compared at the same total length (estimated in Rayanistes and Remingtonocetus, which are missing distal condyles). Scale bar represents 5 cm in each illustration.
