Species
Champsosaurus gigas
Champsosaurus gigasChampsosaurus gigas was an imposing freshwater predator characterized by an exceptionally wide, flared temporal region that housed massive jaw-closing muscles. Its streamlined, flattened body, paddle-like limbs, and slender gharial-like snout allowed it to ambush elusive prey within murky river channels and floodplain lakes. As one of the largest choristoderes, it notably survived the Cretaceous-Paleogene extinction event, continuing to dominate early Paleocene waterways of North America.
PrehistoricAquaticCarnivorous
—observations
—countries
—peak records
ExtinctConservation statusIUCN Red List categoriesLCNTVUENCREWEXExtinctRed List categories, explained →
Diet & preyGars, Bowfins, Teleost fish
Predators
- Borealosuchus
- Larger crocodilians
ThreatsEocene warming, hydrological changes, and ecosystem turnover (historical)
HabitatsFreshwater rivers, lakes, and swampy floodplains
Life spanEstimated 20–30 years
Classification
- FamilyChampsosauridae
- SpeciesChampsosaurus gigas
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Extinct species known only from fossils; safe to observe in museum collections.
Responsible observation
- Museum Observation: Examine the remarkably expanded temporal arches on the skull that anchored powerful jaw muscles.
- Fossil Identification: Look for dense ventral ribs called gastralia, which served as underwater ballast during life.
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