Thursday, September 30, 2010

Backyard Diptera

Lately I have been blogging a lot about butterflies, but those are not the only insects I have come across. Over the course of the summer, I saw a nice variety of flies in the backyard, and now that is is autumn, I am seeing a slightly different set of species. Flies are as Diptera, a large and diverse insect order that includes midges, gnats, crane flies, mosquitos, bee and wasp mimics, and a variety of other forms. Some of them, like mosquitos, no-see-ums, greenheads, and deer flies can be nasty biters. Many others are benign and perform useful services like preying on other insect pests, breaking down decayed material, or pollinating flowers. Here are a few that I have seen in the last week.

The first is a green bottle fly, a type of blow fly. This is in the genus Lucilia, probably L. sericata. It is consistent with that common species's features, anyway. A few other species have similar characteristics. I posted one of these back in June.

The second is a syrphid, Eristalis dimidiata. I have photographed other Syrphidae in the yard, including Toxomerus marginatus and Sericomyia sp. Earlier in the summer, another species in the genus, E. transversa, was very common in the yard. I only started seeing the E. dimidiata recently.

The last is an Asian Tiger Mosquito (Aedes albopictus). The bushy antennae and large palps suggest that this individual is a male. These mosquitos were introduced accidentally to North America in a shipment of tires in the 1980s. Their range is mostly in the southeast, but it extends northward at least as far as New Jersey. In my backyard, these are the only mosquitos I see (and feel) with any regularity. It may be just a subjective impression, but they seem to have a nastier bite than a lot of other mosquitos.