MAYFLY

any slender, small to medium-size (up to 4 cm [1.6 inches]) insect of the order Ephemeroptera usually found around streams and ponds. The approximately 2,000 species are characterized by triangular membranous fore wings, smaller round hind wings, and two or three long, threadlike tails. The mayfly is the only insect to molt after its wings become functional. Wings are held vertically when at rest rather than in the rooflike position typical of most other insects. Chewing mouthparts in the aquatic larvae are vestigial in the adult, which lives just long enough to mate and reproduce. Males dance in large swarms to attract the females. The frantic activity of the adult mayfly has long been of interest to both the poet and the angler: the poet uses it as a symbol of life's ephemeral nature; and the angler, using lures that resemble mayflies, tries to mimic it.