Yes, though mites come in all colors, it looks like the web of a mite to me! Get rid of them before they infest all your plumeria like they did mine this summer. I first tried Natria from Lowe's/Home Depot, an insecticidal soap. It is too hot for Neem oil, an organic -way of ridding mites. I had to resort to insecticide, used Spectacide Triazicide to get rid of them. They will suck the color our of your leaves, have babies by the 1,000's who will do the same. Soon, you will lose your plant. Get rid of them.
