Burgessia bella
Middle Cambrian
Burgess Shale, Stephens Formation
Field, British Columbia, BC, Canada.

17mm essentially complete rare arthropod on 45mm slab

Burgessia is an extinct genus of soft-bodied arthropod of uncertain affinities.  There hasn’t been a consensus on assigning it to a particular family nor order nor class.  It is known only from the Middle Cambrian Burgess Shale.  It is remarkable among arthropods in that in life its telson apparently exhibited some degree of flexibility.

For more information about Burgessia see: Burgessia – Wikipedia

Read the paper re-describing Burgessia here (PDF): Hughes, C. P. (1975, July). Redescription of Burgessia bella from the Middle Cambrian Burgess Shale, British Columbia. In Evolution and morphology of the Trilobita, Trilobitoidea and Merostomata: Proceedings of the Oslo Meeting, 1973 (pp. 415-435).