Carnaúba (Copernicia prunifera).

It's the tree behind the cyclist. Its Brazilian name has a tupi origin, meaning "scratching tree", because its stem is thorny. This tree can grow up to 15 metres high and its leaves are a bit blueish, because of a natural wax coat that prevents the loss of water in the dry season. Cutting out leaves and then leaving them to dry at sun, the coat of wax becomes powdered. Shaking the leaves over a recipient, the powdered wax is gathered and then put in water on a fire to become liquid wax. This wax is used in the production of some types of paper, of lipsticks, of varnishes, of soaps and of vinyl records.
The branches with leaves are used to cover roofs, the fibers are used to make bags, baskets and nets.
The purple ripe fruits are used to feed farm animals. Also flour can be extracted from the pulp. The dry seeds can be toasted and then ground, becoming a coffee substitute.
In Brazil, carnaúbas are abondant in Ceará and in the neighbouring states of Piauí (at west) and Rio Grande do Norte (at east).
The photo was taken at Beira-Mar Avenue, Mucuripe quarter, Fortaleza.