My favorite crane fly memory (I mean, who doesn’t have one of those?) was from graduate school: I was in my bedroom upstairs when all of a sudden my two housemates started screaming in the living room downstairs. I came running down to find them pointing up at a corner in fear, and one of them exclaiming, “That’s the biggest mosquito I’ve ever seen! Just think of the size of the bug bite you would get from that!” To their surprise, I calmly pulled over a chair, stepped up to carefully cup the insect in my hands, and released it out the back door. What I had just removed from our house was not the “biggest mosquito ever”, but rather a perfectly regular sized, and very harmless, crane fly. 

Crane flies are related to mosquitos about as much as they are to houseflies. All are in the order Diptera, the “true flies”. One of the defining characteristics of Diptera species is that they have only one pair of wings. While many other groups of insects have two pairs of wings, including bees and butterflies, in flies the second pair of wings has evolved to be a reduced set of knoblike organs called halteres. Halteres provide an important balancing function, stabilizing the insect as it flies through the air. The halteres on the crane fly pictured here are small round nubs at the end of a narrow shaft just below the insect’s wings. 

As an insect, crane flies have six legs, or at least that’s the way they start out. I have seen their legs referred to as “deciduous”, as they often shed them under stress and/or to escape a predator. As such, it is not uncommon to find a crane fly with fewer than 6 legs. 

Crane flies are an abundant and extremely diverse group of organisms. So much so that they are essentially impossible for anyone but an expert to identify beyond the family level. Just distinguishing between genera is difficult, relying on subtle differences in wing venation. Add to that the fact that according to the Kaufman Field Guide to Insects of North America, there are roughly 1,600 species within the family Tipulidae north of Mexico. With all that said, I am confident that the insect pictured here is a crane fly within the Tipulidae family, but I would be completely guessing if I attempted to differentiate it any further.