Species · GBIF taxon 4965003
Archelon ischyros
Archelon ischyrosArchelon ischyros cruised the shallow waters of the Western Interior Seaway during the Late Cretaceous, propelling its enormous frame with massive, paddle-like front flippers. Rather than carrying a solid bony carapace, its shell consisted of an open framework of struts covered by a thick, leathery hide that dramatically reduced weight in open water. A sharp, hooked beak gave this colossal marine reptile powerful crushing ability to feed on ammonites, squid, and soft-bodied jellyfish.
MarinePrehistoric
Licensed referenceMike Beauregard / CC BY 2.0 · cc-by
—observations
—countries
—peak records
ExtinctConservation statusIUCN Red List categoriesLCNTVUENCREWEXExtinctRed List categories, explained →
Diet & prey
- Ammonites
- Belemnites
- Jellyfish
Predators
- Tylosaurus proriger
- Cretoxyrhina mantelli
- Mosasaurus hoffmannii
ThreatsPredation by mosasaurs and large lamniform sharks; Late Cretaceous extinction event
HabitatsShallow epicontinental seas (Western Interior Seaway)
Life spanEstimated 50–100 years
Classification
- FamilyProtostegidae
- SpeciesArchelon ischyros
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Extinct species; known exclusively from fossil remains in Late Cretaceous rock formations.
Responsible observation
- Museum Exhibits: Observe mounted fossil casts in major paleontology collections to appreciate true scale.
- Fossil Identification: Look for star-like radiating rib structures rather than solid bony shell plates.
Ecological Analog (c) Pam Kleinsasser, some rights reserved (CC BY), uploaded by Pam Kleinsasser · cc-by
Image unavailablePredator 
Predator User:A,Ocram / Public domain · cc0
Close Relative Claire H. from New York City, USA / CC BY-SA 2.0 · cc-by-sa
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