Hoaxtales
Do not you think that these "folktales" are but a crude hoax? Last time it was nails, boxes, etc. This time it is "carai" plant, fried tree frogs etc. Anyone who ever saw a tree frog would doubt its nutritional value, especially when fried. I tested this story against several Latin America, Carribean and Mexican lore resources: nothing. There is no plant called "carai," "karai" in any Indian language. "Carai" is a tribe in Surinam; it also means a shaman; "Carribean" comes from this word. There is, of course, Karai chicken, a popular Indian-Pakistani dish; perhaps that was the inspiration for this "Indian folktale." All spellings of Nofuetoma draw blank. There are no folktales combining sculls, frogs, and toads in any of the lore compendiums. The tale does not sound at all like your typical South America lore. I am skeptical.