Thanks for the ID Jim, I've been finding a few different Flower Longhorns in woodland trails on small tree-like plants with clusters of small white flowers.

That's where I find most of them too. A low (under 4 ft.) herbaceous perennial with a whitish-pink flower cluster is beginning to bloom along roadsides, and you will find a lot of lepturines there. Later, when squash and pumpkin vines are blooming, look inside the blossoms for mating pairs of Typocerus v. velutinus. I've found them mating on/in a variety of blooms, but they seem especially attracted to the squash family. Maybe it's the color.