Molecular Analysis Resolves the Taxonomy of the Laurencia Complex (Rhodomelaceae, Ceramiales) in Bermuda and Uncovers Novel Species of Chondrophycus and Laurenciella

Abstract

ABSTRACT In the last decade, molecular tools have revealed a significant number of previously unrecognized taxa in Bermuda's marine flora, especially among the Rhodophyta. A number of species have been persistently misidentified based on morphological similarities to species described from other localities. Some have been assigned to existing taxa not previously reported for the islands, and many have been determined to be novel species. Of late, researchers have substantially modified the ‘Laurencia complex’ in several regions around the globe. Herein, we confirm the presence in Bermuda of five of the eight genera recognized in this complex – Laurencia J.V.Lamouroux, Chondrophycus (J.Tokida & Y.Saito) Garbary & J.T.Harper, Palisada (Yamada) K.W.Nam, Yuzurua (K.W.Nam) Martin-Lescanne and Laurenciella Cassano, Gil-Rodríguez, Senties, Díaz-Larrea, M.C.Oliveira & M.T.Fujii, and discuss the species historically and presently known in the islands. Both rbcL chloroplast sequences and COI-5P mitochondrial sequences support the recognition of at least two species for what has historically been labeled L. obtusa in Bermuda, these assigned to L. dendroidea J.Agardh and L. catarinensis Cordeiro-Marino & M.T.Fujii in molecular analyses. We present two new species, Chondrophycus planiparvus Popolizio, C.W.Schneider & C.E.Lane, sp. nov. and Laurenciella namii Popolizio, C.W.Schneider & C.E.Lane, sp. nov., the latter genetically distinct from L. marilzae (Gil-Rodriguez, Sentíes, Diaz-Larrea, Cassano & M.T.Fujii) Gil-Rodriguez, Sentíes, Diaz-Larrea, Cassano & M.T.Fujii, L. mayaimii Collado-Vides, Cassano & M.T.Fujii and an undescribed species from Brazil. We also used ITS (rRNA) sequences to explore species limits for Laurencia catarinensis, L. dendroidea and L. microcladia Kützing. A full description of Laurencia microcladia, based on recent collections from Bermuda and the Caribbean Sea, is also included in this study.