Here we have a female (as denoted by the space between the compound eyes) tabanid fly. Every time I’ve seen these flies they have been on plants with flowers with their long proboscises straight down. I’m not sure if they fold up, and I kind of hope not, because it would seem to make those scissors like mouthparts (the little triangular appendages at the bottom of the head) less useful for slicing skin and sucking blood the way their fellow Tabanidae, horse and deer flies, do it. Kind of thinking that is wishful thinking, although maybe not as these flies have never bothered me and as I said seem to be consistently feeding on flowers.
ID is a little fuzzy, seems like it is subfamily Pangoniinae, and if so, likely a Stonemyia sp. But that is only an amateur’s tentative identification.