Sixth addendum to the synoptic review of red algal genera

The sixth addendum to Schneider and Wynne’s 2007 “A synoptic review of the classification of red algal genera a half century after Kylin’s 1956 ‘Die Gattungen der Rhodophyceen’ ” is presented, covering the names of genus- and higher-level taxa added or modified since our fifth addendum ( Bot. Mar. 65: 141–151). Since our original synopsis, we have added 177 genera to the list of red algae in five subsequent addenda, numerically demonstrating an increased amount of genetic work over nearly two decades. In this sixth addendum, we list 49 new genera and three new families from the past three years, as well as listing several genera synonymized with other genera, and other recent taxonomic actions, based primarily on molecular sequencing studies. Six species that were orphaned when Microcladia was subsumed by Ceramium are formally transferred to the latter genus.