Morning glory, Ipomoea sp.,  Family: Convolvulaceae.  Over 500 species in the genus.   Vines, shrubs and trees.

Various species have purgative activity, used as a laxative to relieve constipation (root employed of Ipomoea purga, syn. I. jalapa.  A few species are hemostatic.  Others are claimed as aphrodisiacs and hallucinogens (seeds employed).

Numerous members of the morning glory family inhabit the Hawaiian Islands and are used as food and medicine there to include:  I. indica, I caririca and I. pes-caprae
This species possible I. purpurea (manto de la virgen) found in the Yucatan has been used for hundreds of years Mayan medicine.  Also used by the Zapotecs from which they made the powerful drug badoh negro from the black seeds.  Morning glories of this species grow profusely on the eastern shore of Cozumel island, throughout the Yucatan and in and around Oaxaca.
Ipomoea genus also contains the sweet potato, I. batatas (L.) Lam.  an edible tuber. 

See Below: Try slicing a thin transection of the tuber for the first layer of a vegetable sandwich.  Add roasted peppers, Mesclun greens, cucumber,  olives and a big tasting cheese.   In addition, I have avocado, Vidalia onion and painted lady runner bean blossoms.  An Italian dressing of garlic, olive oil, basil, oregano and light vinegar soaks the sandwich.  Delicious.