Midges

views updated

Midges

Order: Diptera (2 winged insects)

Family: Chironomidae

Over 175 genera and 1000 species

Life Cycle: complete

Four Stage Metamorphosis: egg, larva, pupa, and adult

(Midges sit with their forelegs raised up in the air. Mosquitoes sit with their hind legs in the air.)

Larva

Body Description

The body is wormlike having 3 segments to the thorax, 9 for the abdominal segments with no distinctive gills, visible legs or wing pads with proleg and head. (Mosquitoes have 10 segments) Large eyes are also located on the head. They generally inhabit the bottom of the area they live in and have sinuous undulations or crawling movements. Their body colors are a wide variety of black, grey, olive, yellow, white, cream, ruby, amber, purple, olive green, brown and some contain hemoglobin. They range in size from approximately 1/16-1.

Pupa

Body Description

The midge pupa is distinguished by an enlarged head that appears to be fused as one with the thorax. There are plume like gills on top of the head that look like antennae and also on the tip of the abdomen. Under the top of the thorax are enlargements that hold the folded wings and legs. The segmented abdomen is much smaller than the thorax in diameter. The pupa is free swimming but slow and is a bottom dweller.

Adult

Body Description

The adult has 6 very long slender legs that are 2 to 2 ½ times longer than the entire body and make a round star-like silhouette. When at rest the one pair of wings is flat and lies at a slight angle to the body and can measure up to 1. The antennae are plume like and are especially large on the male. There is not a tail and the abdomen is segmented. The thorax and the head are extra large. Body colors are assorted, anywhere from dark blacks, greens, tans, with light striped abdomen. A few hours after mating both sexes die but dont necessarily fall to the water like the mayflies and therefore are not a significant source of food for trout.