The first record of Sirenia (Mammalia) from the early Oligocene of the Paratethys

Abstract

Sirenians have been extensively recorded from the Mediterranean and west European localities but there are only few finds to the east of it, from the area covered by the Paratethys. For the early Oligocene, to our knowledge, there are no published records of sirenians from inner seas of the Old World. Here we report a specimen of Dugongidae indet., consisting of two partial vertebrae and 12 fragments of ribs, collected in a manganese ore mine in Ukraine and dated as the earliest Oligocene (33–32 Ma). The specimens, as preserved, did not differ in morphology and size from ‘Halitherium schinzii’ and therefore can belong to Kaupitherium, at present the single early Oligocene genus recorded from Europe. However, its vertebral and rib anatomy is not specific for Kaupitherium, so we identify it only by family level. The marks of scavenging on a rib possibly are due to gastropod or bivalve mollusks. The sea, as suggested from biotic data, had a temperate or subtropical climate, relatively cold waters and high diversity of pelagic and deep-water habitats. Thus, the onset of the Oligocene was a period when sirenians could enter temperate inner Eurasian waters, a marginal area in their worldwide dispersal.