Opabinids are organisms resembling the Burgess shale

Burgess Shale

The Burgess Shale Formation, located in the Canadian Rockies of British Columbia, is one of the world's most celebrated fossil fields, and the best of its kind. It is famous for the exceptional preservation of the soft parts of its fossils...

 creature Opabinia

Opabinia

Opabinia is an animal genus found in Cambrian fossil deposits. Its sole species, Opabinia regalis, is known from the Middle Cambrian Burgess Shale of British Columbia, Canada. Fewer than twenty good specimens have been described; 3 specimens of Opabinia are known from the Greater Phyllopod bed,...

, and by inference related to it. The status of the group and its constituent members are very much up in the air, as are the group's relationships with other organisms: some posit a close relationship with the Anomalocaridids.

With Leanchoilia

Leanchoilia

Leanchoilia is a four-eyed arachnomorph arthropod known from the Cambrian Burgess shale. It was about 5cm long and had long, whip-like feelers mounted on frontal arm-like appendages. Its guts are sometimes preserved in three dimensions....

 another species had also been assigned originally to the family opabinidae by Walcott (1912), which no longer holds nowadays

External links

• Palaeos
  Palaeos
  Palaeos.com is a web site on biology, paleontology, cladistics and geology and which covers the history of Earth. The site is well respected and has been used as a reference by professional paleontologists such as Michael J. Benton, the professor of vertebrate palaeontology in the Department of...
  
  Ecdysozoa, look for: Probosciferidea [Opabiniida, Opabiniidacea]