Seen on Isla

I have no idea what this plant is. It grows along the upper areas of the beach on the south end of the island. On the East, open ocean side. It is constantly buffeted by wind and salt spray but yet flourishes. It is definately a creeper type plant. In the fall it bursts into bloom with these purple flowers. Looks like morning glories growing as ground cover. It is stunning when in full bloom. A vast carpet of green with purple dots everywhere.