Tillandsia fasciculata is one of the study species of this work. It performs an alternative form of photosynthesis called CAM, which allows it to survive as an epiphyte in water limiting conditions.
Tillandsia leiboldiana grown in the bromeliad collection of the Botanical Garden of the University of Vienna. It is closely related to CAM-performing T. fasciculata, but in standard conditions it does not perform CAM itself. Instead it collects water in a tank-like structure that it forms with its leaves.