Rugosa Spider Conchs shells for sale in bulk, also referred to as arthritic spider conch because of its crooked fingers protruding from the body of the shell.  These rugosa spider conch shells, sold in bulk, measure between approximately 3 inches and 5 inches in length.   Our rugosa shells are commercial grade and imperfect.  They will have natural imperfections. Great for use in shell decor and crafts.