Species · GBIF taxon 4964997
Protostega gigas
Protostega gigasProtostega gigas cruised the warm epicontinental waters of the Western Interior Seaway, propelled by powerful front flippers built for sustained open-ocean swimming. Its reduced bony carapace featured broad gaps between ribs covered by a tough, leathery hide, cutting buoyancy drag and overall weight. Strong, beak-like jaws enabled it to crush drifting ammonites and shelled mollusks or graze on abundant pelagic jellyfish.
Marine ReptilePrehistoric
Licensed referenceClaire H. from New York City, USA / CC BY-SA 2.0 · cc-by-sa
—observations
—countries
—peak records
ExtinctConservation statusIUCN Red List categoriesLCNTVUENCREWEXExtinctRed List categories, explained →
Diet & prey
- Ammonites
- Jellyfish
- Squid
Predators
- Cretoxyrhina mantelli
- Tylosaurus proriger
- Mosasaurus missouriensis
ThreatsPredation by mosasaurs and large lamniform sharks
HabitatsWarm shallow inland seas and open pelagic marine waters
Life spanEstimated 50–80 years
Classification
- FamilyProtostegidae
- SpeciesProtostega gigas
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Extinct species known exclusively through Late Cretaceous fossil remains.
Responsible observation
- Museum Viewing: Examine articulated skeletal reconstructions mounted in major natural history museums.
- Fossil Formations: Look for Cretaceous marine reptile exhibits showcasing Smoky Hill Chalk discoveries.
Predator User:A,Ocram / Public domain · cc0
Image unavailablePredator 
Ecological Analog (c) Pam Kleinsasser, some rights reserved (CC BY), uploaded by Pam Kleinsasser · cc-by
Close Relative Mike Beauregard / CC BY 2.0 · cc-by
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