Too hot for classic bonsai...
I have some bonsai books which proved inadequate for hot countries, especially those with a Mediterranean climate. Temperature may reach 35c (95F) many times in summer. The air is humid but does not condense into fog, and no rain usually from May to end of October. I am looking for plants which tolerate those temperatures and do not require frequent watering.
Attempts to increase watering for seedlings often results in potting soil degradation and wild humidity fluctuations, so seedlings are usually grown in February, where low temperatures mitigate those effects. Many trees are not available as seeds and a small specimen is purchased and trained as bonsai.
I am a cactus collector and I grown some succulents as bonsai. Many are grown as bonsai because of the habit to develop a caudex (wide trunk or taproot) that is displayed for bonsai effect. I have a book on succulent bonsai as well, but these are not true bonsai in the traditional sense. Nevertheless, I have found two plants which are drought-tolerant and can be grown using traditional bonsai plants, because they have a tree-like trunk which may grow a bark similar to that of trees.
The plant pictured on the left is Euphorbia cap-saintmariensis, the one on the right is possibly a Ruschia species, a member of the Aizoaceae family.