Morphology and systematics of Gelidiella tenuissima (Gelidiales, Rhodophyta) from Gran Canaria (Canary Islands, Spain)

Fertile male gametophytes of Gelidiella tenuissima are described for the first time, from cultured plants collected in Gran Canaria (Canary Islands, Spain). The morphology of male reproductive structures in this species is similar to other gametophytes referred to the Gelidiales, but different from the recently described male gametophyte of the type species of Gelidiella, G. acerosa. Morphological comparisons between these two species, using the male gametophyte and the tetrasporangial stichidia, and also molecular analyses, suggest that two different groups of species are included in the genus Gelidiella.