Scorpion flies are insects known for their distinctive appearance. Males of many species possess a prominent, tail-like genital structure that curves upwards, resembling a scorpion’s stinger. This feature is harmless and used during mating. These insects generally have long, slender bodies, an elongated face resembling a beak, and four membranous wings.
Global Distribution
Scorpion flies are found across most continents. Their greatest diversity occurs in the Afrotropic and Palearctic realms, with significant generic and family diversity also in the Neotropic, Nearctic, and Australasian regions.
These insects are primarily distributed throughout the Northern Hemisphere. They are common in North America, particularly the eastern United States and southeast Canada. European populations are widespread, including western Russia, Germany, Italy, and France. In Asia, scorpion flies inhabit central, eastern, and southern China, Japan, and parts of Southeast Asia (e.g., India, Myanmar, Thailand, Vietnam, Malaysia, Indonesia). They are notably absent from Madagascar and many oceanic islands.
Specific Habitat Preferences
Scorpion flies primarily inhabit moist environments. They are commonly found in deciduous forests, woodlands, and along forest edges. These insects also frequent areas with low shrubs, groundcovers, and hedgerows, often in proximity to water sources like streams or ponds.
Dense vegetation is a consistent characteristic of their preferred habitats. While most species favor humid conditions, some can adapt to semi-desert environments for short periods.
Certain specialized groups, such as snow scorpionflies, are unique in appearing during winter and can be observed on snowfields and moss. Other related groups, like hangingflies, can be found in forests, grasslands, and even caves, all maintaining high moisture levels.
Microhabitat and Environmental Factors
Scorpion flies exhibit specific microhabitat preferences based on environmental factors. They thrive in cool, humid conditions and are sensitive to high temperatures. Eggs require precise moisture levels to hatch and are typically laid in damp soil, leaf litter, or moss. Larvae develop within the moist leaf litter, moss, or on the soil surface.
Adult scorpion flies are frequently observed on the leaves of low-lying shrubs and herbaceous plants, often a few feet above the forest floor. They spend much time crawling in shaded areas, seeking protection from direct sunlight and heat. High relative humidity is a key factor in their habitat selection. Precipitation and elevation are also important determinants of where different scorpion fly species are found. These insects are not strong fliers, tending to remain within suitable microhabitats.