We live in Houston and are having extreme drought currently and temps were very hot all summer. We've had lantana for years, but this year we've been noticing this appearing on them. It only seems to affect this particular variety with this color pattern. All of the other colors (purple, orange, white, gold) don't seem to have developed these.
What is happening on my Lantana?
Well, we DO learn something new every day! I thought your problem looked like aster yellows so did a quick search and, sure enough, I found a site that says lantana can get it too. Here's the site:
I've had some of my purple coneflowers succumb to aster yellows but never any of my lantana. When it attacks my coneflowers I just pull out and dispose of the affected plants. Fortunately, I've never had it attack all of my coneflowers, just one or two at a time.
Thank you very much. After calling Mercer Arboretum they confirmed it was around this year.