New palaeontological assemblage, sedimentological and chronological data from the Pleistocene Ma U'Oi cave (northern Vietnam)

Abstract This paper describes recent material gathered during the second fieldwork at Ma U'Oi in November 2002 by a Vietnamese–French–Japanese team. The Ma U'Oi cave, located in the province of Hoa Binh (60 km SW from Hanoi), northern Vietnam, belongs to a karstic network developed in Triassic dark-grey limestones. The cave is filled with coarse-grained breccias containing numerous fossil remains, partially preserved at several loci inside the cave (wall, vault and ground). We describe new teeth which confirm the occurrence of mammal taxa already mentioned at Ma U'Oi (Bacon et al., 2004)[Bacon, A-M., Demeter, F., Schuster, M., Long, V.T., Thuy, N.K., Antoine, P-O., Sen, S., Nga, H.H., Huong, N.T.M., 2004. The Pleistocene Ma U'Oi cave, northern Vietnam: palaeontology, sedimentology and palaeoenvironments. Geobios 37, 305–314], while others, mainly microvertebrates, emphasize the occurrence of new species for the Pleistocene of Vietnam. We report here, for the first time, the occurrence of these microvertebrates of different groups (primates, rodents, insectivores, small reptiles and amphibians) in the faunal assemblage. Among mammal taxa, the presence of one more hominid affiliated to archaic Homo is also attested by our findings. U/Th dating carried out on 2 samples extracted from breccia speleothems confirms the biochronological estimate, with fossiliferous fillings ranging from late Middle Pleistocene to Late Pleistocene.