A DNA barcode survey of the red algal genus Mazzaella in British Columbia reveals overlooked diversity and new distributional records: descriptions of M. dewreedei sp. nov. and m. Macrocarpa sp. nov

Species of the red algal genus Mazzaella are widely distributed along the west coast of North America with 11 reported in British Columbia (BC). Like many red algal genera, however, accurate species identification is complicated by phenotypic plasticity and convergent evolution, and considerable taxonomic changes have taken place in recent years. To better understand the diversity of this genus in the BC flora, we variously compared COI-5P, rbcL, and ITS data for 407 collections predominantly from BC (n = 347) and California (n = 59) with other accessions in GenBank. We report the first records of Mazzaella phyllocarpa (Postels & Ruprecht) Perestenko in the BC flora whereas Mazzaella linearis (Setchell & N.L. Gardner) Fredericq is excluded--individuals previously assigned to this name referred to Mazzaella dewreedei sp. nov. Verified records and the distributional range for the poorly documented Mazzaella minima (G.J. Hollenberg) P.W. Gabrielson are greatly extended whereas northern records of Mazzaella rosea (Kylin) Fredericq are established. The presence of Mazzaella flaccida (Setchell & N.L. Gardner) Fredericq and Mazzaella japonica (Mikami) Hommersand (likely introduced) inBC are confirmed whereas resolution of the Mazzaella oregona (Doty) J.R. Hughey, P.C. Silva & Hommersand species complex necessitates description of Mazzaella macrocarpa sp. nov. Two additional cryptic complexes involving M. flaccida and M. oregona were discovered in the Californian flora, but are outside the scope of this study and are in need of further investigation. Key words: COI-5P, DNA barcode, Gigartinaceae, Mazzaella, rbcL. Les especes algacees rouges du genre Mazzaella sont largement distributes le long de la cote ouest de l'Amerique du Nord, dont 11 especes signalees en Colombie-Britannique (CB). Comme c'est le cas pour plusieurs genres d'algaces rouges, l'identification precise des especes est compliquee par la plasticite phenotypique et revolution convergente, et des changements taxonomiques considerables ont recemment eu lieu. Afin de mieux comprendre la diversite de ce genre dans la flore de la CB, nous avons compare la COI-5P, la rbcL et des donnees des ITS de 407 collections provenant de fa^on predominante de CB (n = 347) et de Californie (n = 59) a d'autres donnees de GenBank. Nous rapportons les premiers signalements de la presence de Mazzaella phyllocarpa (Postels & Ruprecht) Perestenko dans la flore de CB alors que Mazzaella linearis (Setchell & N.L. Gardner) Fredericq en est exclue--on refere maintenant a Mazzaella dewreedei sp. nov pour identifier les individus anterieurement designes par ce nom. Les signalements verifies et l'etendue de la distribution de l'espece pauvrement documentee Mazzaella minima (G.J. Hollenberg) P.W. Gabrielson sont grandement elargis alors que des signalements de Mazzaella rosea (Kylin) Fredericq sont etablis au nord. La presence de Mazzaella flaccida (Setchell & N.L. Gardner) Fredericq et de Mazzaella japonica (Mikami) Hommersand (probablement introduite) en CB est confirmee alors que la resolution des especes du complexe Mazzaella oregona (Doty) J.R. Hughey, P.C. Silva & Hommersand necessite la description de Mazzaella macrocarpa sp. nov. Deux complexes cryptiques additionnels qui impliquent M. flaccida et M. oregona ont ete decouverts dans la flore californienne, mais ils se trouvent hors des visees de cette etude et doivent etre etudies de maniere plus approfondie. [Traduit par la Redaction] Mots-cles: COI-5P, code-barres genetique, Gigartinaceae, Mazzaella, rbcL.
Introduction The red algal family Gigartinaceae is generally accepted as having nine genera: Chondracanthus Kutzing, Chondrus Stackhouse, Gigartina Stackhouse, Iridaea Bory de Saint-Vincent, Mazzaella G. De Toni f., Ostiophyllum Kraft, [...]