Ephemerellidae

Ephemerellidae is a family of mayflies belonging to the order Ephemeroptera. These insects are aquatic in their larval (nymph) stage, inhabiting a wide variety of freshwater environments such as streams, rivers, and lakes. The nymphs of Ephemerellidae are characterized by their flattened bodies and the presence of three cerci (tail-like appendages), although the middle one is often reduced or absent. They are detritivores, feeding on decaying organic matter found on the substrate of their aquatic habitats.

The adult mayflies, also known as imagos, are short-lived and terrestrial, emerging from the water in large numbers. They do not feed and their primary purpose is reproduction. Adult Ephemerellidae are typically weak fliers and are often found near their emergence sites. They play a role in the aquatic ecosystem by serving as a food source for fish and other predators. The family Ephemerellidae is diverse, with numerous genera and species found worldwide, particularly in temperate regions. Their presence and abundance can be indicative of water quality, as many species are sensitive to pollution.