Arid subtropical support species

A friend is living in Lanzarote, Gran Canaria which is subtropical climate, arid of course. Is there a list of support species that can be used in such a climate? I'm aiming towards legume bushes and trees, but any other support would be great to know! Thanks!

I think they could pull off Tithonia diversifolia as a nutrient accumulator. Eleagnus species are good as well. Pigeon peas and velvet beans are other possibilities - I almost never water those and they do well.