Isotelus

Isotelus gigas · Isotelus was a huge extinct trilobite that lived in warm shallow seas of North America during the Ordovician period.

It lived about 471.3 to 443.1 million years ago.

Isotelus
Photo: Prehistorica CM, CC BY 4.0
Isotelus
Photo: Prehistorica CM, CC BY 4.0
Isotelus
Photo: Dwergenpaartje, CC BY-SA 3.0

Taxonomy

KingdomAnimalia
PhylumArthropoda
ClassTrilobita
OrderAsaphida
FamilyAsaphidae
GenusIsotelus
SpeciesIsotelus gigas

Where its fossils were found

Mainly the eastern and central USA and Canada, with a few finds in Britain and Russia.

Fun facts

  • The biggest Isotelus fossils are over 70 centimetres long, making this genus home to the largest trilobite fossil in the world.
  • Workmen digging a dam tunnel in Ohio first thought a giant Isotelus fossil was a fossil turtle.
  • Isotelus became Ohio's state fossil in 1985 after a group of local students petitioned for it.
  • Baby Isotelus were only 0.6 mm long and drifted in the water as plankton before settling on the sea floor as young adults.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).