Pyrophyllon and Chlidophyllon (Erythropeltidales, Rhodophyta): two new genera for obligate epiphytic species previously placed in Porphyra, and a discussion of the orders Erythropeltidales and Bangiales

Abstract Two new genera, Pyrophyllon and Chlidophyllon, are described to accommodate three species of obligately epiphytic red algae endemic to the New Zealand region, which were previously placed in the genus Porphyra. Although these species all possess rhizoidal holdfasts and packets of spores, and two of the three species produce archeosporangia (characters consistent with the morphological concept of the genus Porphyra), molecular sequence analyses (nuclear small-subunit ribosomal DNA gene) and polysaccharide chemistry data confirm that these epiphytes are more closely related to members of the Erythropeltidales than to the Bangiales. The criteria used to distinguish members of these orders are discussed.