Hey there Picko Jack that is a great looking tree.I am too warm for longans and they don't fruit properly.Are you at high altitude in east java where it gets cool enough to stimulate longan flowering? Maybe it is the indonesian variety you have that can fruit in a truely tropical place.
Yes Mike, its local variety and its been selected as good cultivar for its heavy bearing and good eating quality. its called "Lengkeng Mutiara" (lengkeng = longan, mutiara = pearl) since its aril appearence that says look like transculent white pearl. BUT (just like your saying) its only fruiting well in spesific region with cooler temperature and high altitude (>600 M above sea level) and in matter of fact, almost all longan variety in indonesia need cooler and high alt, or its just gonna be erratic bearing tree. well, at least till view years ago....before inducing longan flower technique with potassium chlorate been found. now small scale longan orcad (up to a hectare) that plant thai and local cultivar can be found all over indonesia...and they fruit well in lowland...even with better quality fruit