Edible seaweed and sea vegetable products are frequently infested with insects. Must be checked.
How to check seaweed for bugs
Narrow leaves or wide leaves.
Check each leaf over a light box. Make sure to check both sides. Any silhouette, white, gray or dark spot should be checked to see if it is an insect. If it is, the insect itself, or that portion of the leaf, should be removed.
See also how to check nori