Lampyridae is a family of insects in the beetle order Coleoptera. They are winged beetles, and commonly called fireflies or lightning bugs for their conspicuous crepuscular use of bioluminescence to attract mates or prey. Fireflies produce a “cold light”, with no infrared or ultraviolet frequencies. This chemically-produced light from the lower abdomen may be yellow, green, or pale red — wavelengths from 510 to 670 nanometers. There are 2,000 species of firefly found in temperate and tropical environments. Many are in marshes or in wet, wooded areas where their larvae have abundant sources of food. These larvae emit light and are often called “glowworms”, particularly in Eurasia. In the Americas, “glow worm” also refers to the related Phengodidae.
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