Saccharina bongardiana is a dark brown annual seaweed that has a single ribless blade that has a smooth edge and two rows of puckers (bullations) running lengthwise. This specimen was about 12 cm long and 4 cm wide. The holdfast was still intact. It can reach 60 cm.
Found washed ashore at the Dungeness National Wildlife Refuge. Can be found in the lower intertidal to subtidal. Found from mid California to Alaska to Russia.