There are two important unconformities in the Calypsostranda Group (late Palaeogene) at Bellsund, Spitsbergen. The first one is the basal angular unconformity of the Skilvika Formation against folded and planated Proterozoic metasediments: the author provides evidence for its primary sedimentary character. The second one is an intraformational erosional disconformity/discontinuity expressed by rapid replacement of coal-bearing terrestrial strata (Skilvika Formation) by shallow-marine strata (Renarddodden Formation).
From a skull and mandible, we describe a new genus and species of a primitive insectivore (Mammalia: Insectivora: Leptictida: Leptictidae). Its large body size and higher−crowned teeth indicate a different feeding ecology from other leptictid insectivores. With evidence of some heavy, flat wear on the molariform teeth, its shift in diet was likely to greater herbivory. Unlike the narrow snout of Blacktops, this new leptictid retains a broad snout, suggesting that small vertebrates were still important dietary components. The specimen was collected from the floodplain deposits of the lower or middle White River Group of South Dakota, which represent the latest Eocene to earliest Oligocene (Chadronian and Orellan North American Land Mammal “Ages”).
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