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One hedgehog (Erinaceus cf. lechei), two moles (Talpa cf. levantis and "Scalopoides" cf. copernici), one shrew-mole (Quyania aff. polonica), and one desman (Desmana cf. polonica) are described from a Late Pliocene (MN17) karst fissure filling near the city of Varshets. Although the material is relatively well preserved, the exact determination was not possible because of the small samples and the fact that the taxonomy of the fossil forms from these groups is in a state of confusion. Up to now Late Pliocene remains of "Scalopoides" copernici and Quyania polonica have been known from Poland only. The occurrence of similar forms in Bulgaria during the Villanyian is considered as a relic situation, due to locally favorable conditions. The described insectivore assemblage is indicative of a temperate and humid climate, similar to the present-day conditions in SE Bulgaria.
Nyctitheriids are primitive insectivores that were relatively abundant and diverse in North America and Europe during the middle Paleocene through to the middle Oligocene. The nyctitheriids from Asia are poorly known and show several distinctive characters. Here we describe the late Paleocene Asionyctia guoi gen. et sp. nov., the first fairly well known Asian nyctitheriid, from the Subeng locality near the city of Erlianhot (Erenhot) in Inner Mongolia, China. Among its most conspicuous features are the paraconid positioned high on p4, the rather primitive morphology and size of p3, the premolariform P4/p4 and the transverse upper molars with a small, straight postcingulum. Except for the paraconid positioned high on p4, these combined features are also present in other Asian nyctitheriids, but absent in North American or European forms. We performed a cladistic analysis, based on a set of 20 dental characters, to resolve higher−level phylogenetic relations within Nyctitheriidae. The strict consensus tree groups all Asian forms in a single clade, for which we propose the rank of a subfamily and the name Asionyctiinae subfam. nov. Within Nyctitheriidae, a semimolariform P4/p4, as in Leptacodon tener, is considered primitive, and we consider the morphologically simplified P4/p4 of Asionyctiinae derived within Nyctitheriidae. Asionyctiinae can be derived from an American, primitive Leptacodon−like ancestor migrating into Asia, with the reduction of P4/p4 occurring on the Asian continent. Considering the derived morphology and the relatively high diversity of Asionyctiinae during the Asian late Paleocene, and the inferred conservative nature of the family Nyctitheriidae, we suggest an early Tiffanian time for the migration of nyctitheriids into Asia.
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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