OBJECT DOSSIER · SMITHSONIAN OPEN ACCESS

Alligator — Stangerochampsa sp.

SAGE Museum Deep Time scientific dossier

Date / Period

Late Cretaceous — Maastrichtian broadly; exact display specimen age not yet established · Exact age and locality of the individual Smithsonian display specimen remain unresolved in the verified source set.

Object Type

composite cast

Medium

representative_scientific_visual

About This Object

Geologic period: Late Cretaceous — Maastrichtian broadly; exact display specimen age not yet established

Age: Exact age and locality of the individual Smithsonian display specimen remain unresolved in the verified source set.

Taxonomic note: Named Stangerochampsa material is well documented from the early Maastrichtian Horseshoe Canyon Formation of Alberta. That does not justify automatically assigning this Smithsonian Stangerochampsa sp. display to Hell Creek.

Feeding: Predatory and opportunistic feeding is consistent with alligatoroid anatomy.

Locomotion: Semiaquatic locomotion.

Body plan: Low-slung semiaquatic crocodylian body with a broad skull and armored skin.

Evidence: The exhibit identity is direct museum evidence. More precise age and locality require the individual catalog record.

Why it matters: Crocodylians were already established components of Late Cretaceous freshwater ecosystems and survived the end-Cretaceous extinction.

Plain Language Identity: An extinct alligatoroid crocodylian represented in the Smithsonian river-edge display as Stangerochampsa sp.

What You Are Looking At: A composite cast representing an extinct alligatoroid.

Ecosystem: Freshwater river-edge ecosystem.

Preservation: Visitor object is a composite cast.

Room Context Note: Use this as a broader river-edge comparative object until the exact specimen provenance is verified.

Open Questions: Exact locality, formation and species remain unresolved.

Source Urls: https://naturalhistory.si.edu/visit/virtual-tour/current-exhibits/deep-time-virtual-tour-fossil-list; https://www.scielo.org.mx/scielo.php?pid=S1405-33222019000300727&script=sci_arttext

Enrichment Method: SAGE curated research pass; title + scientific name + source scene matched; display reconstruction separated from evidence; provenance uncertainty retained

Scientific name: Stangerochampsa sp.

Evidence / representation: Representative evidence-type visual; not the exact specimen.

Why It Is In This SAGE Exhibit

Representative evidence-type visual; not the exact specimen.

T. rex & Triceratops: The Last American Dinosaur World.

Provenance

Smithsonian Deep Time source scene: Main Circulation Path and Age of Humans Bridge

Exhibition History

Included in the SAGE Museum Dinosaurs & Deep Time staging exhibit.

Subjects & Themes

Stangerochampsa sp. Late Cretaceous — Maastrichtian broadly; exact display specimen age not yet established composite cast Main Circulation Path and Age of Humans Bridge T. rex & Triceratops

ORIGINAL COLLECTION SOURCE

This object page stays inside SAGE Museum. The Smithsonian link below is provided only as the original scholarly collection record. It opens separately.