Bee Fly in the family Bombylidae and genus Xenox. Photo by bee watcher Jeff Polley.
We previously posted about common flower visiting flies in the NYC area, but bee watcher and blogger (www.thissideofscience.com) Jeffrey Polley recently brought a few more to our attention. The above massive fly has been seen recently (mid July 2010 but has been seen in previous years too). This appears to be a Bee Fly (Family Bombylidae) in the Genus Xenox. Despite its imposing size (close to 1 inch long!), it does not bite or cause harm to humans. Rather, these flies feed on pollen and nectar and thus are pollinators. On the opposite end of the size spectrum, the below Flutter Fly is tiny (<1/4 inch long) and rarely noticed when present. However, Flutter Flies are quite common and exhibit the interesting behavior of rhythmically rotating their wings. This makes it appear as if they are “waving” and they have also been called “waving wing flies”. Larvae feed on plants or beetles and adults of some species feed on flowers. Beyond this, little is known about their biology or how they live.
Flutter Fly, in the family Pallopteridae and genus Toxonevra. Photo by bee watcher Jeff Polley.