Odaraia, An Enigmatic Chengjiang Biota Arthropod

Description: This specimen from the Chengjiang Biota, like the first example found nearly 20 years ago is comprised of the posterior part of an enigmatic organism known as Odaria ? eurypetala. The question mark indicates that the generic assignment is still in dispute. Recently-discovered, more complete specimens preserve the carapace (see artist’s restoration), and point out affinities with Odaraia alata from the Burgess Shale, but that assignment is not accepted by all researchers.

The diversity of soft-tissue fossils from Chengjiang is astonishing: algae, medusiforms, sponges, priapulids, annelid like worms, echinoderms, arthropods (including trilobites), hemichordates, chordates, and the first agnathan fish make up just a small fraction of the total. Numerous problematic forms are known as well, some of which may have represented failed attempts at diversity that did not persist to the present day.

Also see: Chengjiang Biota