Protocardia subquadrata

Geological context: Late Cretaceous, Fox Hills Fm, Timber Lake Mbr. Collection locality: float and in place, includes many concs., from Sphenodiscus Layer up through CAZ, road cut and adjacent outcrops along W side of SD Rt. 63, from High Elk Hill to point .5 mi N, & between 5.5 and 6 mi S of intersection with US Rt. 212, High Elk Hill, 6 mi SSW of Eagle Butte village, Ziebach County, South Dakota, USA. Collected by Karl M. Waage, 1940/1941. IP number 599865; lot count 1; taphonomy=concretion; accn=IPA.07048; associatedwith=on same slab: IP.599865,IP.599869,IP.599870,IP.599871,IP.599872,IP.599873,IP.599874,IP.599875,IP.599876,IP.599877,IP.599878,IP.599879,IP.599880,IP.599881,IP.599882,IP.599883,IP.599884,IP.599885,IP.599886,IP.599866,IP.599867,IP.599868.