Granadillas (Passiflora ligularis) are often confused with Maracuya (Passiflora edulis) because they look similar, especially the yellow maracuyá (passion fruit). However they taste different, granadillas are sweet while maracuyá are more acidic.
Granadillas, Passiflora ligularis, commonly known as the Sweet granadilla or Grenadia is a plant species in the Passiflora genus. The epithet ligularis comes from the plant’s ligulate corollae. It is native to the Andes Mountains between Bolivia, Venezuela and Colombia. It grows as far south as northern Argentina and as far north as Mexico.
The fruit is between 6.5 and 8 cm long and between 5.1 and 7 cm in diameter. The outer shell is hard and slippery, and has soft padding on the interior to protect the seeds. The seeds, which are hard and black, are surrounded by a gelatinous sphere of transparent pulp. The pulp is the edible part of the fruit and has a soft sweet taste. It is very aromatic and contains vitamins A, C, and K, phosphorus, iron, and calcium. (source: Wikipedia)