I don't know the variety or cultivar. The local Asian market seems to have the same Longan and Lychee each year, at least they don't claim different names on them and they always look the same to me. When I've asked they've said that the fruit came from Florida but I seem to remember them saying that the Longan came from Hawaii that year. I know that every seed sprouted and grew, this one grew faster and appeared stronger. I moved into this house in 2010 and it was a year or two after that move that I sowed those seeds so this tree is less than 7 years old.
I tend to sow every seed I find in tropical fruit just to see if it will grow. There is only so much room in the greenhouse so I focus my collection on smaller trees. I've had good luck getting things to sprout but bad luck getting them to live for years and years. Besides this tree I have a purple fruited Passionvine (Passiflora edulis) that fruits well, a strawberry guava, some Suriname cherries and even a Key Lime tree (a friend sprouted and grew the seedling but gave it to me when it got too big). My big failures have been guava trees, I love eating the fruit but when I grow out the seeds they never taste as good as their parent - after 3-4 years of waiting! Other seed grown plants in the collection that have not fruited but are otherwise healthy are Jabuticaba, Cherimoya, Sapodilla, Indian fig Opuntia, a Luc's Garcinia, an Opuntia from Nullzero (doing great!) and some Jungle plums and Grumichamas from Oscar.
There is also a lot of fruiting plants that I bought as grown trees - Papayas, lots of Citrus.