Ephemeroptera, commonly known as mayflies, are aquatic insects with delicate, transparent wings and elongated bodies. They are known for their extremely short adult lifespan, ranging from a few hours to a few days. Mayflies are important ecological indicators and play a critical role in freshwater food webs, serving as prey for fish and other aquatic animals.

Ephemeroptera, commonly known as mayflies, are distributed globally. They are found on every continent except Antarctica. Their presence is widespread across Europe, North America, Asia, Africa, Australia, and parts of South America.

Mayflies typically inhabit freshwater environments, such as streams, rivers, lakes, and ponds. They require clean, well-oxygenated water for their nymphal stages and are often indicators of good water quality. The larvae, or nymphs, are aquatic and are usually found in habitats ranging from fast-flowing streams to stagnant ponds, depending on the species.

Mayflies play a crucial role in freshwater ecosystems, serving as a food source for a variety of fish and other aquatic organisms. They are also involved in nutrient cycling as they feed on algae and detritus. Some species are adapted to specific environmental conditions, such as colder mountain streams or warmer, lowland waters. Their life cycle includes a short-lived adult stage, which is primarily focused on reproduction.