YPM 23166

Late Cretaceous, Fox Hills Fm, Timber Lake Mbr, Cucullaea Assemblage Zone. Concretion, about 8 ft below level of 1957 Sphenodiscus concs., upper sand, sand bank, RR cut at Lantry Dam, 1.5 mi WNW of Lantry, Lantry Quad., CENTER SW SW Sec4T12NR22E. Dewey Co., South Dakota, USA. Collector: Waage, K.M. 1957.