The flowers remind me very much of Eranthemum pulchellum. Leaves not at all, though. Bracts are there but different. Here in subtropical Florida, many plants can grow in the well drained sandy expanses, but survive in an attenuated, prostrate form. Maybe this is a related plant. I have never seen this growing wild, but it always has rich dark green leaves and the white and green bracts. Flowers not as profuse and crowded as in your pic, though. Still, easily one of my favorite non-natives. Maybe this will help someone get closer to an ID.
A deeper search shows that Eranthemum pulchellum is in the International Plant Names Index as Eranthemum capense. Searching on that I got to efloraofindia and indiabiodiversity.org both of which have further information, beyond my desire to translate from the technical classification arguments.