Opabinia regalis is an extinct, stem group arthropod found in the Middle Cambrian Burgess Shale Lagerstätte of British Columbia. Opabinia was a soft-bodied animal, measuring up to 7 cm in body length, and its segmented trunk had flaps along the sides and a fan-shaped tail. The head shows unusual features: five eyes, a mouth under the head and facing backwards, and a clawed proboscis that probably passed food to the mouth. Opabinia probably lived on the seafloor, using the proboscis to seek out small, soft food. Fewer than twenty good specimens have been described; 3 specimens of Opabinia are known from the Greater Phyllopod bed, where they constitute less than 0.1% of the community.
Opabinia
Top left: retouched image of Opabinia (Walcott Cambrian Geology and Paleontology II by Charles Doolittle Walcott)
The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At 508 million years old, it is one of the earliest fossil beds containing soft-part imprints.
Ottoia, a soft-bodied worm, abundant in the Burgess Shale. (From Smith et al. 2015)
Satellite image of the area.
Walcott Quarry of the Burgess Shale showing the Walcott Quarry Shale Member. The white parallel vertical streaks are remnants of drill holes made during excavations in mid-1990s.
