This caught my eye across the boardwalk so, of course, I made a beeline for it. Turns out this strange fruit is the nonnative Bitter Melon (Momordica charantia).
While it originated in India, this edible fruit is now grown throughout the tropics. Though this is the showy stage, according to my research, the fruit is actually best consumed when green. With a texture like a chayote the flesh has a slightly bitter taste, hence the common name.
What I found most interesting is the medical potential of the plant. It is being studied for its hypoglycemic effect as well as possible cancer prevention and even infection fighting. Not just another attractive face!