What insect is this?

They could be gnats.

fruit flies?

Yep, maybe fruit flies…maybe you need to clean out your desk. lol

I don’t think they’re fruit flies. Doesn’t look like the ones here http://en.wikipedia.org/wiki/Drosophila_melanogaster

Do they look somewhat triangular, wings and all?

Sort of. They look just like the period on a standard keyboard.

More details:
* I don’t own any pets
* The insects do not fly very high. They can only fly short distances.

Sounds like fruit flies…go cash in your beer bottles already. :p

Fruit flies move slow, and don’t ever seem to go very high…yet, you can never catch them…And no they don’t bite. Not sure to what extent they can be harmful if you don’t get rid of them though, if that is what they are.

Drain flies!
Er, I read nullos post and thought it was the main one. I should go to bed.

Take a close look. Do they have hard outer wings? Do they have visible antennae?

looks similar to the drain fly but the wingspan is not as wide

Aaah, all the cool life forms, I say set out a bowl of nectar and throw the flies a party!

@delirium That’s them. Drain flies, you say? Thanks!

Is there like a version of the drain fly that has smaller wings?

Maybe they are phorid flies. I would google “phorid flies” and look at the pictures to compare. They may be fungus gnats too.

Bingo. The ones I saw looked exactly like this: http://www.hydro-gardens.com/images/Fungus_Gnat_Size_small.jpg

Well, I cleaned my desk. Hope they’re gone now.

Well, ya know…the best soloution is to keep a small frog in your desk. lol

I have an army of tree frogs that live in my yard, very few bugs.

pet kermit!

@Symbeline fruit flies are not black

I think in reality it is impossible to positively id this from the characteristics given- there are many flies that are as you describe.

Well, they’re so tiny that they will appear black, unless they were to be totally white.