moth
moth, (superfamily Noctuoidea), any of about 160,000 species of overwhelmingly nocturnal flying insects that, along with the butterflies and skippers, constitute the order Lepidoptera. Moth are distributed nearly worldwide. Although their larvae may be destructive to certain plants—and several moth species are economically significant pests—many moths are important pollinators of the world’s wild and domesticated flowering plants, and all stages of their life cycle are important to local food webs. For more detailed coverage, see also Lepidoptera and list of butterflies and moths.
Moths vary greatly in size, ranging in wingspan from about 4 mm (0.16 inch) to nearly 30 cm (about 1 foot). Highly adapted, they live in all but polar habitats. The wings, bodies, and legs of moths are covered with dustlike scales that come off if the insect is handled. Compared with butterflies, moths have stouter bodies and often duller coloring. Moths also have distinctive feathery or thick antennae. When at rest, moths either fold their wings tentlike over the body, wrap them around the body, or hold them extended at their sides, whereas butterflies hold their wings vertically.
(Read Britannica’s essay “What’s the Difference Between Moths and Butterflies?”)
As with all lepidopterans, the moth life cycle has four stages: egg, larva (caterpillar), pupa (cocoon), and adult (imago). The larvae and adults of most moth species are plant eaters, though some adults lack mouthparts and do not eat. Larvae in particular can do considerable damage to ornamental trees and shrubs and to many other plants of economic importance. The bollworm and measuring worm are two of the most destructive types of moth larvae. Some moth species (especially those of the family Tineidae, which includes the clothes moth) eat wool, fur, silk, and even feathers.
Major families
Some of the better-known moth families include:
- Gelechiidae, to which the destructive bollworms of cotton, corn, tomatoes, and other crops belong.
- Tortricidae, or leaf roller moths, which are forest pests.
- Lymantriidae, the tussock moths, also containing forest pests such as the spongy moth.
- Arctiidae, the tiger moths, with many brightly colored tropical species.
- Olethreutidae, including several destructive species such as the codling moth and the peach moth.
- Noctuidae, the owlet moths, one of the largest families of lepidopterans.
- Saturniidae, the giant silkworm moths, containing the largest individuals.
- Geometridae, measuring worm moths, including the waves, pugs, and carpet moths.