Mystery solved! I just confirmed that it is a Solanum Rantonnetii. Now to learn more about it...
Great. Your leaves are a good match. The current accepted name is
Lycianthes rantonnetii, you will find it in Wikipedia under the
Lycianthes name. There is pretty good information on it in Wikipedia.
Question, are you able to grow this outdoors, or is it only going to be indoors? It will be easier to keep happy as an outdoor tree, though it is one of the trees marketed for indoors.
It is not really a tree, it is a woody herbaceous shrub in the tomato family. Related more to Goji berry (
Lycianthes chinensis) and other desert shrubs.
Likes half day to full day of sun.
Likes to be kept moist, it is not a desert shrub, even though it is in a family with some desert dwelling species. As bonsai use a deciduous potting media mix, an all inorganic conifer mix is too dry for this species.
Probably best styled for bonsai by "clip & grow", as woody stems will be brittle. Branches that still have green bark will back bud. Stems that have developed brown rough bark will not back bud. So always keep some green on branches you want to keep.
It may sucker from the roots. IF you allow suckers 6 months or more to develop, you can remove them at the next repotting, and pot them up as separate plants.
Best is brought inside to avoid frosts, if your area does get cold.
Should root from cuttings.
Hope this helps.
