Temporal range: Late Carboniferous (Pennsylvanian) – Recent
Mayfly are insects whose aquatic larvae (called naiads or nymphs) live months, up to a year, in freshwater. The adults are extremely short-lived, from 30 minutes to one day, depending on the species. The function of the adult imago is reproduction and dispersal; they do not eat.
Mayflies are unique in that they moult one more time after getting functional wings (this is also known as the alate stage). This second-to-last winged stage is usually very short, a matter of hours. The stage is a favourite food of many fish, and many 'fishing flies' are modelled on them.
It often happens that all the mayflies in a population mature at once (the hatch), and for a day or two in the Spring or Autumn (Fall), mayflies will be everywhere, dancing around each other in large groups, or resting on every available surface.
The adults have various special features. Their rear wings are small or almost vestigial; the males have two long front legs for holding females, the rest have no function. Mating is usually in mid-air.
- from the Greek ephemeros = ephemeral, or short-lived; pteron = wing. The name refers to the most distinctive features of the adults.
- 'Ancient wings'
- They mat not be a natural monophyletic group: see Trueman, John W.H. 2008. Tree of Life Web Project – . Version of 2008-Mar-20. Retrieved 2008-Dec-15.
- Moult or ecdysis: shedding the cuticle (exoskeleton) of arthropods.
- Hoell H.V; Doyen J.T. & Purcell A.H. 1998. Introduction to insect biology and diversity. 2nd ed, Oxford University Press. p320. ISBN 0-19-510033-6.