The role of secondary attachment discs in the survival of Chondracanthus squarrulosus (Gigartinales, Rhodophyta)

Abstract The ecological role of secondary attachment discs and crusts generated by propagules in the survival of Chondracanthus squarrulosus was evaluated. Based on in situ observations and the introduction of substrates, both the secondary discs and the crusts were found to persist under conditions of stress and produce new shoots that form part of the next generation of C. squarrulosus. The percentage of plants resulting from the surviving discs of the previous generation on the substrates introduced corresponded to 22% of new recruits. This study suggests that secondary discs can play an important role in the perennial survival of this species, in addition to the annual reproduction by spores (78%).