any member of the approximately 12,000 species of the insect family Tenebrionidae (order Coleoptera), so named because of their nocturnal habits. These beetles tend to be short and dark; some, however, have bright markings. Although found on every continent, they are more common in warm, dry climates. Most members feed on dry, decomposing vegetation or animal tissue. Some bore in wood; others feed on larvae or live in ant nests.
Learn more about darkling beetle with a free trial on Britannica.com.