Eye gnat, genus Liohippelates

While working in the yard on a hot afternoon, July 9, 2017, a couple of these eye gnats (probably Liohippelates) came after me, so to speak. They were incredibly aggressive, flying all around my face, and landing on me. I was very sweaty. I killed one, and then this second fly came. I went inside, got my bug net and a vial of alcohol, and within a minute of two, this fly was all over me again. When it flew near my ear, I could hear the high pitch of its wings beating (but not as high a pitch as a mosquito). He is preserved in the vial now.  Columbia California, 9 July 2017. Thanks to Dr. Lynn Kimsey with the ID.