In the past week I've seen three or four bright green butterflies flying around. Not in my garden, but in my travels. They were flying and I was in my car and didn't see them land. Anyone know what they could be? I've never seen them before. They looked to be just a plain bright green with no markings.

Also, off and on over the summer I've seen by my butterfly bush small yellow butterflies and small orange butterflies. No markings on those either.

I've googled them both, but can't find anything like them.