Scientific name: Tyrannosaur Dinosaur Premaxillary Tooth - Nanotyrannus sp (cf Aublysodon) - Theropod Dinosaur Tooth Location: South Dakota (Private Land), USA Geological Formation: Hell Creek Fm Age: Late Cretaceous, Maastrichtian stage (~68-66 Million Years) Size: 16mm REF.: #J477 DESCRIPTION: Nanotyrannus lancensis is a small, fast, agile tyrannosaur from the Late Cretaceous Hell Creek Formation (originally part of the Lance Formation), known for being small and distinctly different from T. rex, with recent studies confirming it's a separate species, not a juvenile T. rex, based on unique features like more teeth, larger hands, and distinct bone structures. Meaning "dwarf tyrant," it was a capable predator of smaller prey, coexisting with T. rex. Key Facts Name Meaning: "Dwarf tyrant" from Greek nanos (dwarf) and tyrannos (tyrant). Species Name: lancensis refers to the Lance Formation where its skull was found. Size: Around 15-18 feet long, much smaller and lighter than an adult T. rex. Habitat: Hell Creek Formation (Late Cretaceous), same time and place as T. rex. Lifestyle: Fast, agile pursuit predator, likely hunting smaller dinosaurs like pachycephalosaurs. Controversy: Long debated as either a distinct species or juvenile T. rex, but recent evidence strongly supports it as its own genus. Distinguishing Features: Narrower skull, more teeth, larger hands, and different bone structures than T. rex. The Debate & Resolution Juvenile T. rex Theory: Many scientists thought smaller tyrannosaur fossils from Hell Creek were young T. rex because no large Nanotyrannus fossils existed, and T. rex juveniles were rare. Separate Species Theory: Researchers found that Nanotyrannus fossils showed adult-like traits (fused bones) and unique features that T. rex never developed, making it biologically impossible to grow into a T. rex. Current Consensus: Nanotyrannus is a separate, distinct genus of small tyrannosaur, coexisting with T. rex as a unique, agile predator. Aublysodon teeth from the Hell Creek Formation (typically Montana/South Dakota, not Iowa) are generally considered to be non-serrated premaxillary teeth from juvenile or subadult Tyrannosaurus rex, rather than a distinct genus. These rare, D-shaped teeth are often sold by collectors as "Aublysodon" or "Nanotyrannus," showcasing a smooth,,,Sometimes striated appearance. Key Details on Hell Creek "Aublysodon" Teeth: Classification: Aublysodon is considered a nomen dubium (doubtful name). The teeth are widely recognized as juvenile T. rex. Characteristics: These teeth are characterized by lacking serrations (non-denticulate) on the premaxillary (front) teeth. They may show longitudinal striations, giving them a faceted appearance. Occurrence: While Aublysodon was originally described from the older Judith River Formation, similar-looking teeth are found in the late Maastrichtian Hell Creek Formation. Size: They are typically small compared to adult T. rex teeth, often measuring less than 1 inch in length. Discovery: These fossils are found in the Hell Creek formation of Montana and Dakota, often in sandy or clay layers, frequently as isolated finds. All of our fossils come with a Certificate of Authenticity. Every week, the issued Certificates of Authenticity are updated in our database verification system on our website. If you find that your certificate has not yet been updated, please contact us and we will update it immediately. Display box included. IMPORTANT SHIPPING INFORMATION: Our company is based in the USA, but our headquarters and products are located in Europe. Therefore, ALL PRODUCTS WILL BE SHIPPED FROM EUROPE. Consequently, any European customer will receive their shipment without any import charges, as it will be an intra-community shipment. For customers in the USA: Shipments will be made via UPS from Europe, and in this case, we will be responsible for any import charges. These will be paid online by us before the package arrives. Therefore, US customers will not pay any import fees. For the rest of the world: We are not responsible for any import charges applicable to the destination country.