Phantom midge (Charborus sp.)


Phantom midges are tiny non-biting flies, so named because their larvae are transparent aquatic organisms.  The larvae live in small ponds, lakes, and standing pools.  They pupate and emerge as small, non-biting adults.  The females lay their eggs in jelly-like discs on the surface of the water.  The adults are quite common in large swarms over lakes in the spring and summer.  The larvae have antennae that have been modified into mouthparts suitable for grasping other organsims as prey.  Adults live about six days during which time they mate and lay eggs.  Eggs hatch in two to four days.  Larvae can develop in six to eight weeks.  The first two instars are strongly phototactic while staying near the bottom, while the third instar may prefer living in the sediment itself.   The larva can overwinter in this instar if needed.  Fourth instar larvae migrate up and down the water column in response to atmospheric pressure.  When pressure is high (day), they stay in the sediment; when pressure is low (night), they move to the surface.  Pupation takes from one to two weeks.

Availability: These need to be ordered and will be available after spring break.

Housing:  You will need either an aquarium, a small jar of water, or a shallow pan.  You should have a thin layer of sediment on the bottom for later-instar larvae.  Larvae will rise to the surface to pupate, at which points you may want to put a lid on your container.  You can move adults to a small jar with a water-soaked cotton ball for moisture. 

Food: The larvae will eat Daphnia, other aquatic larvae smaller than themselves, and other small aquatic organisms.