Hanging flies on a Spiderweb

This picture was taken when I was trying to click a spider in its web .I found these insects moving in pairs hanging from  the web and gliding around it without getting entangled.It appeared as if they were performing a synchronised  dance .Later, I learned that these are Gall Midges (Cecidomyiidae).This trapeze act is apparently a widespread phenomenon in the Cecidomyiidae, especially in the subfamilies Porricondylinae and Cecidomyiinae. The behavior was first reported (published) in 1853 by Johannes Winnertz.

Spider webs are used as roosting places for a certain species of gall midge, family Cecidomyiidae.  When  most flies become tangled in spider webs and eventually a become  meal for the spider, these tiny flies are able to select the non-sticky foundation threads of spider webs and safely suspend themselves from them. Predators of these  flies would risk of being entangled in the spider web .

Really fascinating to know that  such small insects have adapted themselves  to thrive on something  like spider web which  is a death trap for so many other larger insects.