undet. Scaphitidae
From the collection of Yale Peabody Museum. Free to download, adapt and use — no permission needed.
Geological context: Late Cretaceous, Fox Hills Fm, Trail City Mbr. Collection locality: SW-facing bluffs of SE-trending spur that joins terrace to S and SE, 2 mi WNW of Little Eagle, Corson County, South Dakota, USA. Collected by Karl M. Waage, 1959. IP number 314932; lot count 1; taphonomy=concretion; accn=IPA.07048; associatedwith=on same slab: IP.314932,IP.314936,IP.314940,IP.314941,IP.314942,IP.314944,IP.314945,IP.314946,IP.314947,IP.314949,IP.314951,IP.314952,IP.314953,IP.314954,IP.314955,IP.314956,IP.314957,IP.314960,IP.314961,IP.314933,IP.314934,IP.314935,IP.314937,IP.314938,IP.314939,IP.314943,IP.314948,IP.314950,IP.314958,IP.314959,IP.314962,IP.314963.
Yale Peabody Museum’s own description