The Bartonian Eocliff Limestone, Sperrgebiet, Namibia, has yielded early specimens of the exclusively African mammalian family Chrysochloridae. The material from Eocliff comprise the most complete and informative fossil specimens of the group ever found, with good representation of the skulls, mandibles, dentition and post-cranial skeleton. As such the assemblage sheds a great deal of light on the fossil record of this enigmatic family, indicating that it split from the other afrotherians a long time prior to the Bartonian. The fossils are surprisingly modern in many ways, leaving little doubt about their affinities to extant golden moles, but there is a suite of primitive features in the skeleton and dentition which reveals details of their ancestry. The dentition is extremely zalambdodont, but the lower molars have large talonids and the upper molars possess large protocones. The post-cranial skeleton shows many modifications indicating a sand-swimming lifestyle as in extant members of the family but there are several important differences in post-cranial anatomy. The family is not particularly closely related to potamogalids, the superficial dental resemblances in the two families being due, in the main, to convergent evolution - the underlying structures of the teeth are quite different, even though the molars can, in the two families, be described as zalambdodont. Material from the Fayum, Egypt, classified as Eochrysochloris, is probably not a chrysochlorid. A new genus and a new species are erected for the Namibian form. Keywords: Chrysochloridae, Late Eocene, Namibia, Evolution, Zalambdodonty, Sand-swimming.