Mayflies

• Aquatic insects are generally the most conspicuous life forms in streams, ponds and lakes.  Certain species can reach tremendous numbers. 
• Many molt into winged adults and some become pests in and around nearby buildings. 
• Mayflies are also known as shadflies and lakeflies. 
• Actually, they are not "flies" at all, but are insects in the order Ephemeroptera. 
• Their eggs are deposited in water and the nymphs live at the bottom of streams, pools and lakes.  
• They feed on small aquatic plants, animals and organic materials. 
• These insects lead a very uncertain life, being the chief food of many aquatic insects and fishes.
• There is usually one generation of mayflies per year. 
• The adults are attracted to lights at night and often occur in tremendous numbers during the summer when they make a pest of themselves by their mere presence in and around houses.
• Mayflies are a major source of inhalant allergy.  This insect is unique in molting once after it gets its wings.  Shed skins and dried bodies of dead mayflies break into small pieces and are carried by the wind to be inhaled, sometimes affecting the sufferer far from its original source.