Using molecular data to resolve the taxonomic limits of the genera Callophyllis, Euthora and Pugetia (Kallymeniaceae, Rhodophyta)

SUMMARY Callophyllis is the largest genus in the red algal family Kallymeniaceae and includes over 50 described species. Since its description, there has been considerable debate over the circumscription of this genus relative to related genera. Specifically, the genus Euthora has sometimes been placed in synonymy with Callophyllis , and a number of species of Pugetia have been transferred to Callophyllis . Phylogenetic analyses based on sequences of nuclear large‐subunit ribosomal DNA for representatives of the Kallymeniaceae were completed to assess the various taxonomic proposals surrounding Callophyllis, Euthora and Pugetia . Results indicate that the genus Callophyllis (as generally recognized) is polyphyletic. Callophyllis cristata occupies a position in the trees separate from the remainder of Callophyllis species (including the type Callophyllis variegata ), supporting recognition of Euthora as a distinct genus. Callophyllis chilensis and Callophyllis firma group with the type species of Pugetia, Pugetia fragilissima , thus confirming an earlier taxonomic decision to include these species in the latter genus. A discussion of the relative merits of various reproductive versus vegetative features for assigning species among these three genera is provided. Though outside the scope of the current study, relationships among species of Callophyllis sensu stricto must be visited in light of the results. Although the remaining six species of Callophyllis included in the present trees unequivocally form a monophyletic group, two isolates identified as Callophyllis pinnata (from California and Chile) do not group together, illustrating the confusion generated from the morphological variation within this genus.