Lovebugs
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Bibionidae
March flies, lovebugs, honeymoon flies
Bibionidae is a family of medium-sized flies (Diptera) comprising approximately 650–700 species worldwide. Adults are characterized by thickset bodies, moniliform antennae, and distinctive stout spurs on the front tibiae used by females for digging. The family includes notable genera such as Bibio, Dilophus, and Plecia—the latter containing the famous 'lovebugs' known for prolonged copulatory pairing. Adults of many species are nectar feeders and important pollinators, while larvae are soil-dwelling decomposers and occasional plant pests.
Plecia
Lovebugs, March flies
Plecia is a genus of march flies in the family Bibionidae, commonly known as lovebugs. Several species, particularly Plecia nearctica, are notable for their distinctive mating behavior where males and females remain coupled in flight for hours or days. Adults are small flies, typically 6-9 mm long, with sexual dimorphism in head size—males possess large, bulbous compound eyes while females have relatively tiny heads. The genus includes both extant and fossil species, with fossil records dating from the Cretaceous through the Pleistocene. Some species have become significant nuisance pests due to their mass emergences and attraction to automobile exhaust.