The moth is found in the south central Provinces of Guizhou, Hubei, Gansu, Qinghai, Shanxi, Sichuan, Sizang, Yunnan, and Zhejiang. Infected caterpillars are often found in soft soil under trees in mountains over 4000 m high, or in cold, well-drained grassy marshlands. The life cycle of uninfected moths takes two years to complete. Most other moths have shorter life cycles. Hepilus fabricius and other species of Hepialus live in vertical tunnels in the soil and emerge at night to feed on roots or aerial portions of plants.
Some species are serious pests of pastures.
The use of the caterpillar fungus is believed to have started a thousand years ago. It was either ground into a powder, or mixed with other tonics. Today the most common way to prepare the caterpillar fungus is to stuff a duck with the caterpillar fungus then after boiling the duck in hot water, patients drink the liquid. It sounds unpleasant, but Vivian reports the aroma is pleasant and the broth tastes sweet. The caterpillar fungus is reported to have many benefits as a traditional medicine.