Fibulacaris is a monotypic genus of fossil arthropod known only by one species, Fibulacaris nereidis, discovered from the Cambrian Burgess Shale of Canada.

[1] It was characterized by a bivalved carapace with an inverted rostrum, sandwiching the slender body with stalked eyes and homonomous appendages.

[1] It was probably an actively swimming filter feeder and possibly swam upside-down like some branchiopod crustaceans and horseshoe crabs.

[1] Phylogenetic analysis suggest it was a relative or member of Hymenocarina, which contains other bivalved arthropods.

This prehistoric arthropod–related article is a stub.