Here’s what to do about these occasional invaders. You’re pulling out the holiday décor, or you just opened a cabinet or moved a book, and out scuttles a tiny, flat insect covered with silvery scales.

Silverfish are harmless but destructive pests that feed on starchy items like paper, glue, and fabric. They sneak in through cracks and love humid, cluttered spaces. Seal gaps, cut moisture, and tidy ...