A new locality, called Phu Nam Jun (the "hill of the spring"), is reported from Phu Kradung Formation, northeastern Thailand. According to age constraints provided by the overlying formations, the Phu Kradung Formation may be regarded as either Late Jurassic or basal Cretaceous in age. Systematic excavations conducted in spring 2002 and winter 2003 by the Department of Mineral Resources of Thailand, in collaboration with the Palaeontological Research Centre of Mahasarakham University, the French CNRS and the Musée des Dinosaures d'Espéraza, yielded more than one hundred and twenty fish specimens. All but two specimens belong to Lepidotes buddhabutrensis. One specimen is a semionotid-like fish and one is a skull roof with associated jaws of a lungfish. According to preliminary observations on 1) the spatial distribution of specimens, 2) the mode of preservation of carcasses, 3) the location of the lungfish and 4) the general composition of the fauna, it is suggested that the carcasses dried out prior to fossilisation.