Halisaurus
Halisaurus was a small, sleek marine lizard that swam in the warm seas of the Late Cretaceous. It was not a dinosaur, but a mosasaur, a relative of today's monitor lizards. It used its long tail and flippers to chase fish and other prey.1
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Fun facts
Halisaurus was named by famous fossil hunter Othniel Charles Marsh in 1869.1
It was a small mosasaur, only about 3 to 4 metres long, much smaller than giants like Tylosaurus.1
Its flippers were not as specialized as those of later mosasaurs, so it was probably a slower swimmer.1
Fossils of Halisaurus have been found on every continent except Australia and Antarctica.2
The species Halisaurus onchognathus is known only from remains that were destroyed during World War II, so scientists are not sure if it was a real species.1
Halisaurus lived from about 85 to 66 million years ago, during the Late Cretaceous.2
Most asked questions about Halisaurus
?How big was Halisaurus?
Halisaurus was about 3 to 4 metres (9.8 to 13.1 feet) long, making it small for a mosasaur.1
?Was Halisaurus a dinosaur?
No, Halisaurus was not a dinosaur. It was a mosasaur, a marine lizard related to today's monitor lizards.1
?What did Halisaurus eat?
Halisaurus likely ate small fish and other small prey, based on its slender jaws and numerous small teeth.1
?Could Halisaurus swim fast?
No, Halisaurus was probably a relatively poor swimmer because its flippers were not as specialized as those of later mosasaurs.1
?When did Halisaurus live?
Halisaurus lived during the Late Cretaceous, from about 86 to 66 million years ago.1
?Where have Halisaurus fossils been found?
Fossils have been found on every continent except Australia and Antarctica, including North America and North Africa.1
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Myth buster
Myth: Halisaurus was a dinosaur.
Truth: Halisaurus was a mosasaur, a marine reptile closely related to modern monitor lizards, not a dinosaur.1
For dino experts
- Scientific name
- Halisaurus
- Named by
- Marsh 18692
- Group
- Mosasaurs
- Family / clade
- Mosasauridae2
- Classification
- Mosasauroidea2
- Age of the rocks
- 86 to 62 million years (Santonian / Danian)2
- Rock formations
- Navesink, Severn, Marshalltown2
- Countries
- USA, Morocco, Chile, Peru, Jordan, Angola2
- Fossil records
- 30 in the Paleobiology Database2
- Discovery
- Halisaurus was named by Othniel Charles Marsh in 1869 based on a partial skull and vertebrae found near Hornerstown, New Jersey.1
- Still debated
- Scientists are not sure how many species of Halisaurus really existed, because some fossils are very fragmentary.1
Where the facts come from
- Halisaurus (en.wikipedia.org)
- Halisaurus in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.
Every fact on this page has a number that points to its source. If we got something wrong, sorry, we are dino fans, not a science journal. Tell us at [email protected] and we will fix it.
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