A late Pleistocene fossiliferous paleokarst site in the Western Mecsek Mts (Bükkösd, SW Hungary)

Abstract

In the framework of a project studying the karst region of the Western Mecsek Mts in 2018–19, a new paleokarst cavity containing abundant vertebrate remains was found near the village of Bükkösd, extending the sparse Quaternary vertebrate record of the region. Th e herpetofauna is represented by a salamandrid, a true frog, lacertid lizards and colubrid snakes, the latter dominating the vertebrate material. Th e poor mammal material shows that the area was inhabited by insectivores, bats, mice, hamsters and voles. Th e vertebrate remains show no signs of long transport. Th e composition of the total vertebrate fauna suggests a sunny, rocky hillside with scrub and trees in places in the immediate vicinity of the accumulation site. Th e age of the charcoal recovered from the cavity fi ll (41–42 ka) suggests that the fauna is late Pleistocene (MIS 3), this makes the assemblage the fi rst proven MIS 3 fauna in southern Hungary. Th e re-evaluation of the paleokarstrelated fossil material previously reported from the Mecsek revealed a further assemblage probably also of MIS 3 age, the Mélyvölgy Rock shelter. Th e palaeoclimate reconstructed from the palaeoecological analysis of the faunas is warmer than that from coeval sites in northern Hungary, with more closed (forested) vegetation than the northern mammoth steppes. Th is refers to the existence of a north-south thermal gradient in the Carpathian Basin at the time. Th e U-series dating of speleo thems showed that the karst cavity had existed for more than 0.5 Ma. During MIS 3, the cavity stopped to be part of an active karst conduit and it was fi lled up by loess-derived silt. Th e site was lying above the karst water table then, and it may have acted as a trap either for the live animals or for the bones deposited on the surface. With 25 figures and 3 tables.