Cut in half to reveal it's fleshy, sweet and tarty pulp.
I Googled passionfruit to find some history of the plant and it is THANKS to New Zealand Passionfruit Growers Association for providing it.
The purple passionfruit (Passiflora edulis) is a native of the rainforest margins in the Amazon region of Brazil and perhaps also of Paraguay and northern Argentina. It has adapted to the cooler sub-tropics and the high altitude tropics.
There are many other passiflora species spread widely around the globe and about 50 species are native to New Zealand, Australia, the Pacific and South East Asia.
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The flower...
Passionfruit acquired its name from Spanish missionaries who thought parts of the plant's flower resembled different religious symbols. The Jesuit missionaries who accompanied the Conquistadors to South America saw in its striking flower a means of illustrating the Crucifixion; the 10 petals and sepals represented the apostles, the crown of thorns was seen in the filaments, the five anthers represent the five wounds, the three stigmas were allied with the nails used to pierce the hands and feet of Jesus and the vine's tendrils were equated with the whips.
Flower image courtesy of Google images.