Bizzare unknown fly with huge eyes
Location:  Fairfield, Maine USA
August 13, 2010 2:51 pm
Dear Bugman,
I found this fly on my Cruiser and another under an apple tree leaf. The one on the car seemed very aware of my presence and at one point seemed to be doing some kind of ”defending it’s territory dance” at me! It was about a half inch long (just the body.) It had very bright green large eyes and two very long appendages coming out of its tail end. Is this a stage of life for a dragonfly, or just an adult of something entirely different? It looks like it could be related…can you identify this please?
James R


Hi James,
These are beautiful images of a Mayfly, even though it is August.  Though Mayflies are most common in the spring, especially May, they may also be found at other times of the year.  Whenever they are found, there is one thing that is constant.  They do not live long as winged adults, many dying the first day.  The name for the order, Ephemeroptera, is explained on BugGuide as:  “from the Greek ‘ephemeros’ (of or for a day; short-lived) + ‘pteron’ (wing; feather) refering to the short time that adults are on the wing
.”  Mayflies are unique in the insect world in that they molt twice once they are winged and capable of flight.  The aquatic nymphs metamorphose into subadults or subimages which are called duns by anglers.  They molt a second time into true adults or images which are called spinners by anglers.  According to BugGuide:  “Adult (imago): body delicate or “flimsy”, varying from almost transparent to white, yellow, orange, green, brown, or black; thorax and abdomen bare, often shiny; legs slender, solid color; front legs often held forward and sometimes upward in front of head when at rest; forewings large, triangular, with many cross veins; hindwings much smaller than forewings (hindwings absent in some species); both wings usually transparent but sometimes patterned, held vertically and together above thorax when at rest  Pre-adult (subimago): wings cloudy in appearance, body dull and pubescent, with appendages somewhat shorter — but otherwise similar to imago; pre-adults molt a final time to become adults  Nymph: body elongate, flattened or cylindrical, usually greenish or brownish but color varies according to the type of food eaten; legs long; antennae short; abdomen with lateral plate-like gills and usually three long thin tail projections (cerci); some species have only two cerci.”  We believe your specimen is a Common Burrower Mayfly in the family Ephemeridae, based on images posted to BugGuide.


Hi Daniel,
Thanks so much for the i.d. and detailed information!
Interesting how the body color is affected by diet.
Best wishes,

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