EPOW - Ecology Picture of the Week

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Not a Giant Mosquito

Credit & Copyright:  Dr. Bruce G. Marcot
  

Explanation:  Sometimes confused with a giant mosquito (inducing mosquitophobia) is this amazing and harmless insect called the giant western crane fly.   Growing up to 1.4 inches (3.6 cm) in length with a wingspan of up to 2.75 inches (7.0 cm), they are the largest fly west of the Rocky Mountains in North America and one of the largest flies in the world.       They are often found at night around porch lights, as I found these wonderful specimens at a remote mountain cabin in the mountains of eastern Oregon. Adults do not eat and live essentially only to reproduce.  Larvae are worm-like and feed on decaying plants in wetlands, thereby serving an ecological function of helping to recycle biotic material and nutrients.       What is really amazing about crane flies is how they fly.  They have only one pair of (fore)wings.  The hind wings, however, are modified into spoon-like appendages called halteres, as shown in the following photo:      Halteres vibrate during flight and serve to bring stability to the flight path, working as gyroscopes. Scientists have worked out the neural control of the wings and halteres, to understand how flight is balanced and maintained in flies.   Information:      Fox, J.L., and T.L. Daniel.  2008.  A neural basis for gyroscopic force measurement in the halteres of Holorusia.  Journal of Comparative Physiology A 194(10):887-897.      Fry, M.A., and M.H. Dickinson.  2001.  Fly flight: a model for the neural control of complex behavior.  Neuron 32(3):385-388.