Placodus in 3D - click the head, a leg, or the tail for a fact (full controls on the Dinosaurs 3D hub).
Placodus was a marine reptile, not a dinosaur - it foraged for shellfish on the seafloor of shallow Triassic coastal seas, so the model stands on four sturdy legs rather than swimming with flippers. Published length estimates run about 2 to 3 m.
Colors are an artistic reconstruction (fossils don't preserve them). The measurements in the panel are the real published ones.
Placodus 3D Viewer
The Placodus model below rotates as you drag - zoom in and click any body part for a quick fact, or see the Dinosaurs 3D hub for the full control list.
Placodus was a stocky marine reptile that lived in the Middle Triassic, roughly 247 to 237 million years ago, foraging on shellfish along the shallow coastal seas of what is now Central Europe and China. Published length estimates run about 2.5 to 3 m, with some sources citing closer to 2 m; it was not a dinosaur, and unlike streamlined open-ocean swimmers such as mosasaurs, it kept four sturdy legs for walking along the seafloor. Its name means "plate tooth": broad, flat teeth lined the roof of its mouth and lower jaw for crushing shellfish, while a few forward-pointing chisel-like teeth likely pried mollusks off rocks.
Placodus was named in 1833 by Louis Agassiz, and its fossils have been found across Central Europe - Germany, France, and Poland - as well as China. Thick, dense ribs (a condition called pachyostosis) added ballast to the body, much like a diver's weight belt, helping it stay submerged while it foraged.
| Measure | Figure |
|---|---|
| Length | about 2-3 m (range; commonly cited near 2.5-3 m) |
| Weight | no rigorous scientific estimate; a popular figure of about 227 kg (500 lb) is widely repeated |
| When it lived | 247-237 million years ago (Middle Triassic, Anisian-Ladinian) |
| Group | Marine reptile (placodont), not a dinosaur |
| Diet | Durophagous - crushed shellfish and mollusks |
Colors here are an artistic reconstruction - fossils don't preserve them; the numbers above are real published values, with a range given where sources disagree.
See also Ichthyosaurus and Mosasaurus, other marine reptiles from different lineages.
Frequently Asked Questions
Was Placodus a dinosaur?
No. Placodus was a marine reptile - a placodont - that lived alongside the earliest dinosaurs but belongs to a separate group. This viewer includes it because placodonts are a distinctive, frequently searched part of Triassic marine life.
How big was Placodus?
Published length estimates run about 2 to 3 m, with most sources citing 2.5-3 m. No rigorous scientific mass estimate exists; the roughly 227 kg (500 lb) figure sometimes quoted is a popular estimate, not a peer-reviewed calculation.
Why did Placodus have such unusual teeth?
Its name means "plate tooth". Broad, flat teeth lined the roof of its mouth and lower jaw, forming crushing plates for shellfish, while a few forward-pointing chisel-like front teeth likely pried mollusks loose from rocks.
Is the model scientifically accurate?
The body shape follows fossil reconstructions - a stocky trunk on four legs, with a long tail - but the skin color and texture are an artistic reconstruction. Fossils preserve bone, not color. The figures shown are real published values.