Name:
Sphenodiscus lenticularis Age: Cretaceous Formation: Fox Hills Formation Location: South Dakota Size: Ammonite is over 3 inches across This specimen is not for sale Click here for similar specimens that are for sale
This is a very nice US ammonite. It is a Sphenodiscus lenticularis from the Late Cretaceous of South Dakota. This type of ammonite is extremely lenticular in shape. The planispiral shell of the cephalopod has a very sharp keel. This distinct ammonite is well preserved, and the intricate suture pattern is readily seen. The dark brown coloration of the fossil is quite striking and contrasts beautifully with the grayish-brown matrix. The ammonite is wonderfully presented on the natural block of concretionary matrix that also contains MANY other fossils. This is a very fine example of this unusual ammonite from the Fox Hills Formation.