Subclass Pterygota Division Exopterygota Order Ephemeroptera Mayflies Cadisflies

Subclass: Pterygota

Division : Exopterygota

Order : Ephemeroptera (Mayflies; Cadisflies )

Classification of Order: Ephemeroptera Order : Ephemeroptera(mayflies) Family : Ephemeridae Genus : Ephemera Genus : Hexagenia Genus : Litobrancha Genus : Pentagenia

(Greek, ephemeros = short-lived; pteron = wing) General Characters of order : Ephemeroptera 1 -shape : Slender insects with soft body. 2 -size : small to medium sized insects with an average wingspan up to 15 mm 3 -Body is divided into : a) Head : Short, fine antennae. Compound eyes large, usually Covering most of the head. Vestigial mouthparts.

b)Thorax : 2 pair of membranous wings, Hindwings much smaller than the forewings. front wings large, triangular. hind wings smaller, fan-shaped. Front legs long and often held out in front body. c) Abdomen : Abdomen slender, bearing two (or sometimes three) long terminal filaments. 4 - Metamorphosis : gradual metamorphosis. Mating occurs during flight and large swarms of mayflies close to the fresh water. Eggs are laid on the water surface. Upon hatching the nymphs live on the bottom. Development can take from several months up to a year and can involve from 20 to 50 molts depending on the species.

Mayfly nymphs are aquatic and have a similar body shape to the adults but lack wings. The nymphs have gills along the sides of their abdomen, which look similar to fine leaves.

5 - habitat : Adult mayflies occur everywhere but are always found near freshwater environments. The nymph are aquatic and each species has preferences for a different type of habitat, which is influenced by factors such as water temperature, flow rate, chemical composition and light. 6 - Feeding : Adult mayflies do not feed. The nymphs feed on aquatic plants and other associated organisms. 7 - Economic Importance: Mayflies feed the fish that humans find valuable. The adults and immature also used in fishing.

8 – Examples : Ephemera Hexagenia Mayfly nymph