Opabinia

Extinct stem-arthropod species found in Cambrian fossil deposits

Opabinia regalis is an extinct stem group marine arthropod found in the Lagerstätte of the Burgess Shale (Middle Cambrian, 505 million years ago) of British Columbia. Opabinia was a soft-bodied animal, measuring up to 7 cm in body length, and had a segmented trunk with flaps along its sides and a fan-shaped tail. The head showed unusual features: 5 eyes, a mouth under the head and facing backwards, and a clawed proboscis that most likely passed food to its mouth.

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