Fig. 1

Resynthesis of lichen Usnea hakonensis. Co-culturing of the mycobiont (U. hakonensis: lower left) and the photobiont (Trebouxia sp.: upper left) isolates initiates the development of a symbiotic thalloid structure (centre), which is not a true thallus but presents morphologically and biochemically similar features as a natural thallus (right). The images were taken by the authors