opuntiads.com
Opuntia dillenii, beach prickly pear cactus, spines
Opuntia dillenii is a coastal prickly pear cactus of the southern Atlantic coastal states and perhaps the western coast of FL. Maybe some of the Islands were home to it in pre-Columbian times. However, the species has spread to other continents including South America, Africa, Australia, and Asia and is an invasive cactus in some of these new areas.