A Molecular Investigation of Mazzaella (Gigartinales, Rhodophyta) Morphologically Intermediate Between Mazzaella linearis and M. splendens

摘要: The red algal genus Mazzaella presents an interesting challenge to systematists and ecologists. two species M. linearis splendens are easily distinguished in their ideal form; however, areas of intermediate wave exposure individuals form a seemingly continuous grade between the species. On basis ecological investigations, it was concluded that forms distinct at level plants morphology can be best assigned splendens. Field-identified 'classic' (17 each), as well (20 individuals), were collected. Sequences internal transcribed spacer (ITS) ribosomal cistron determined for all these individuals, related spp. Molecular phylogenetic analyses confirmed close relationship splendens, identified closest relative, sanguinea. Pairwise distance comparisons within (including plants; 0-4 differences) (0-2 less than variation (8-12 differences), both solidly clustered monophyletic (M. sanguinea outgroup; 0-2 differences among four isolates) confirming results investigations. Two further aspects earlier studies also discussed: conclusion stipe length is reliable character distinguishing species; and, suggestion displays slightly heteromorphic alternation generations, being tetrasporophytes (preferring moderately wave-exposed habitats) whereas gametophytic with preference wave-sheltered habitats.