trilobite: Quick Facts

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Facts

Also Known As	Trilobitomorpha

Photos

trilobite fossil

Close-up of a trilobite fossil embedded in brown rock, showing the segmented body and ridged exoskeleton.

Line graph showing the number of marine animal families from the Precambrian era to the present, with illustrations of key groups such as trilobites, ammonoids, marine reptiles, and diatoms. The graph highlights major extinction events and a rise to 1,900 living families today.

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Topics

Flexicalymene holmiid Agnostida Polymerida redlichiid Paradoxides Deiphon Ameura Calymene Greenops dinosaur crustacean Australopithecus pterosaur Arthropleura ichthyosaur plesiosaur oreodont ammonoid placoderm

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Alexandre Brongniart, plaster medallion by David d'Angers

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French geologist

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Animal Factoids

Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters

Animal Group Names