Dragonfly vs. Mayfly

I often get the questions: "Is it true that dragonflies live just one single day?" I understand that non-odonatologist easily mix up dragonflies and damselflies with mayflies, that live just one day as flying insect.

Mayflies are close relatives of Dragonflies and damselflies, but Mayflies are tinier, the largest mayfly in Sweden Ephemera danica is less than 25 mm (1 inch) long. The fore wings of a mayfly is much larger than the hind wings and the wings are kept vertically while resting, the antennas are large and at the tail has two or three long feelers.

Swedish mayflies live as larvae in the water for one or two years. As winged insect the mayfly can't eat, therefor their life is short, sometimes as short as a few hours, but some species can live almost one week. The Latin name for mayfly; ephemeros means "living one day", the Swedish name for mayfly is Dagslända is another name on the same theme, it means "Day-fly".

Dragonflies and damselflies live much longer. As larva in the water the Swedish dragonflies live normally between 2 and 4 years, but in northern Sweden they might be larvae as long as 10 years, due to the cold and dark climate. Damselflies live as larvae 1 to 3 years, except for Sympecma fusca that live as larva only 8-10 weeks. When the dragonfly or damselfly has hatched to flying insect it lives a very dangerous life, some birds love dragonflies for dinner. In the National museum of Natural History in Stockholm one can see a stuffed falcon with a Aeshna juncea) in it's claw. Wagtails (Motacilla alba) are well known as dragonfly predators, Many insects and spiders predate dragonflies and even other dragonflies might eat the dragonfly. Therefore many dragonflies die young and it's hard to determine for how long time dragonflies live. Referring to Sandhall damselflies normally lives two or three weeks, but some damselfly might be as old as nine weeks at best. Dragonflies live longer, large hawkers (Aeshna) might live up to ten weeks, in laboratories it has been living for 13 weeks. As a rule of thumb one can say the larger dragonfly, the longer life.

Page updated June 21 2008
Copyright 2004-2008 Martin Peterson