VERY RARE Fossil Heteromorph Ammonite SCAPHITES NODOSUS – Fox Hills Formation, Maastrichtian, Cretaceous: South Dakota, USA

Description Presenting a VERY RARE and scientifically valuable fossil heteromorph ammonite: Scaphites nodosus, from the Fox Hills Formation, part of the Pierre Shale Group, collected in South Dakota, USA. This specimen is a striking example of a heteromorph ammonite with its distinctive coiled-to-uncoiled shell morphology, emblematic of ammonite evolutionary experimentation during the Late Cretaceous. Scaphites nodosus belongs to the family Scaphitidae, superfamily Scaphitoidea, and order Ammonitida. This species is noted for its characteristic compressed shell with a partially uncoiled body chamber, and prominent tubercles or nodes along the ribs—traits that have fascinated paleontologists for decades. Geological & Scientific Details: Scientific Name: Scaphites nodosus Fossil Type: Heteromorph Ammonite Geological Period: Cretaceous Stage: Maastrichtian (approx. 72–66 million years ago) Formation: Fox Hills Formation (Pierre Shale Group) Location Found: South Dakota, United States Order: Ammonitida Superfamily: Scaphitoidea Family: Scaphitidae Morphological Features: Strongly ribbed, tuberculate shell with an initial tightly coiled inner whorl followed by a straight to recurved outer body chamber Depositional Environment: Shallow marine setting along the margins of the Western Interior Seaway Scaphites nodosus is widely used in biostratigraphy for the Maastrichtian stage due to its well-defined stratigraphic range and unique morphology. Its shell design and ornamentation make it a standout species among Cretaceous heteromorph ammonites. All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity. Please Note: Scale Rule Squares / Cube = 1cm – full sizing is shown in the photo The fossil pictured is the exact specimen you will receive, carefully selected for quality, preservation, and scientific interest This exceptional ammonite fossil is ideal for collectors, educators, or anyone fascinated by the diversity and evolutionary history of ancient marine life.