Ipomoea imperati

Ipomoea imperati, the beach morning-glory (a name it shares with "Ipomoea pes-caprae"), is a species of flowering plant in the family Convolvulaceae. Like "Ipomoea pes-caprae", its seeds disperse by floating in seawater. It has been found on the sandy shores of every continent except Antarctica.
"Ipomoea imperati" and "I. pes-caprae" can be easily can be distinguished in that "I. imperati" has white flowers and "I. pes-caprae" usually has purple flowers. The leaves of "I. imperati" are more linear or lanceolate while those of "I. pes-caprae" tend to be more circular or ovate.
It is considered an invasive species in some places.