Aurantia is my next subject from the Passiflora Society International seed sale. This is an Australian species, once of the few passiflora native to the "Old World." A few years ago I bought some seed on Ebay, but they never germinated. Hopefully, I'll have more success with this one.
One other thing--these macro seed photos aren't to scale with one another. Their size varies widely, but I try to "fill the frame" as much as possible to reveal the maximum amount of detail. Aurantia is the smallest seed I've worked with yet--it's actually smaller than the head of a pin. I know, because I Photoshopped out the silver crescent of the pin head I'd mounted it to. Amazing something so small can grow into such impressive vines.