A molecular phylogenetic analysis of the Bangiales (Rhodophyta) and description of a new genus and species, Pseudobangia kaycoleia

Abstract

K.M. Müller, J.J. Cannone and R.G. Sheath. 2005. A molecular phylogenetic analysis of the Bangiales (Rhodophyta) and description of a new genus and species, Pseudobangia kaycoleia. Phycologia 44: 146–155.

A red alga collected from the Virgin Islands (VIS7) superficially resembles Bangia but was found to have characteristics distinct from known members of the Bangiales. This alga is distinguished by having multiple chloroplasts per cell; as many as nine were observed in one cell. Each chloroplast has a single pyrenoid. In the 18S ribosomal RNA (rRNA) gene sequence analyses, this entity is well supported as being a member of the Bangiales. The relationship between this collection and other bangialean collections is unclear; it appears to be associated with a clade of B. fuscopurpurea from the Atlantic and the Pacific, but this relationship is only moderately supported by neighbour-joining bootstrap. The sequence divergence between the VIS7 collection and other collections of Bangia and Porphyra ranged from 6.9% to 12.6%. This amount of divergence is greater than that observed within many of the clades in the 18S rRNA gene sequence analyses and is slightly less than that noted between the Bangiales and the outgroups used in the analyses (11.6–17.8%). Based on these data, we propose a new genus and species within the Bangiales, Pseudobangia kaycoleia. Molecular analyses showed that neither Bangia nor Porphyra is monophyletic and both may encompass several genera.

ACKNOWLEDGMENTS

This research was supported by CFI (Canada Foundation for Innovation), OIT (Ontario Innovation Trust) and NSERC (National Science and Engineering Research Council) grants to K.M.M. and by NSERC grant RGP 0183503 to R.G.S. Technical assistance in DNA sequencing by Angela Holliss is gratefully acknowledged. The authors are grateful to Mary Koske, Blair Brace, Ron Deckert, Alison Sherwood and John Stiller for collecting and providing samples of Bangia and Porphyra, and to the culture collections: University of Texas Culture Collection (UTEX), Culture Collection of Algae and Protozoa (CCAP) and Provasoli-Guillard National Center for Culture of Marine Phytoplankton (CCMP).