When aspergillosis hits the fan: Disease transmission and fungal biomass in diseased versus healthy sea fans (Gorgonia ventalina)

► Inoculating healthy fans with A. sydowii failed to induce aspergillosis signs. ► Grafting diseased and healthy tissues in situ failed to induce aspergillosis. ► Purpling likely a non-self-recognition response. ► Ergosterol concentration higher in healthy tissues than in diseased tissues. ► Considerable gaps understanding aspergillosis and coral-associated fungi.