Cryptogamie,Bryologie, 2010, 31 (1): 3-205 © 2010 Adac. Tous droits réservés Marine algal flora of French Polynesia III. Rhodophyta, with additions to the Phaeophyceae and Chlorophyta Antoine D. R. N’Yeurt a* &Claude E. Payri a, b a UMR 7138,Systématique,Adaptation,Evolution,Equipe Biodiversité Marine Tropicale, IRD-Nouméa - BPA5, 98848 Nouméa cedex,New Caledonia b Laboratoire Terre-Océan,Université de la Polynésie française,B.P. 6570 Faa’a 98702, Tahiti,French Polynesia (Received 8 October 2009, Accepted 23 December 2009) Abstract — This third paper in a monographic series on the marine macroalgae of French Polynesia gives a detailed coverage of the species of Rhodophyta occurring in these islands. A total of 197 taxa are presented (195 Rhodophyceae, 1 Phaeophyceae and 1 Chlorophyta; of these, 84 (or 43%) represent new records for the flora, while 7 (or 3.6%) are new species. The new combination Jania subulata (J. Ellis et Solander) N’Yeurt et Payri is made for Haliptilon subulatum (J. Ellis et Solander) W. H. Johansen. Padina stipitata Tanaka et Nozawa (Phaeophyceae) and Codium saccatum Okamura (Chlorophyceae) are notable additions to the flora from deepwater habitats in the southern Australs; 56 taxa (or 28.7%) occur only in the Austral archipelago. The flora has most affinities with that of the Hawaiian Islands (Sørensen Index = 0.30), followed by the Cook Islands and Samoa (SI = 0.26 each) and the Solomon Islands (SI = 0.25). There are some disjunct distribution patterns for several subtropical to temperate species, possibly suggesting special oceanic current routes between the southern Australs, Hawaii and the Southern Australian region. algae / biogeography / distribution / floristics / French Polynesia / Rhodophyceae / new records / taxonomy Résumé — Ce troisième volet d’une étude sur la flore marine de la Polynésie française donne une distribution détaillée des espèces de Rhodophycées qui sont présentes dans ces îles. Un total de 197 taxons sont présentés (195 Rhodophycées, 1 Phaeophycée et 1 Chlorophycée), dont 84 (soit 43 %) sont nouveaux pour la flore, et 7 (soit 3,6 %) représentent des nouvelles espèces. La nouvelle combinaison Jania subulata (J. Ellis et Solander) N’Yeurt et Payri est faite pour Haliptilon subulatum (J. Ellis et Solander) W.H. Johansen. Padina stipitata Tanaka et Nozawa (Phaeophyceae) et Codium saccatum Okamura (Chlorophyta) sont nouveaux pour la flore, provenant d’habitats profonds dans les îles les plus sud des Australes ; 56 taxons (ou 28,7 %) ont été trouvés seulement dans l’archipel des Australes. La flore a le plus d’affinités avec l’archipel Hawaiien (Index de Sørensen de 0,30), suivi par les îles Cook et Samoa (SI = 0,26 chaque) puis par les îles Salomon (SI = 0,25). Une répartition disjointe pour un nombre d’espèces sous-tropicales à tempérées suggèrerai un lien particulier par les courants océaniques entre l’archipel des Australes du sud, l’archipel Hawaiien et la région sud-australienne. algae / biogéographie / distribution / floristique / Polynésie Française / Rhodophyceae / nouveaux reports / taxonomie *Correspondence and reprints: [email protected] Communicating editor:Frederik Leliaert 4A. D. R. N’Yeurt &C. E. Payri INTRODUCTION This study gives a detailed overview of the marine species of Rhodophyta (along with two new records of Phaeophyceae and Chlorophyta) occurring in French Polynesia, and supplements and revises the taxa previously reported by Setchell, (1926), Payri &Meinesz (1985a, b), Payri &N’Yeurt (1997), Payri et al. (2000) and Conte & Payri (2002, 2006). The Phaeophyceae and Chlorophyta of French Polynesia, as well as the history of early phycological collecting in these islands, were treated in Payri &N’Yeurt (1997) and N’Yeurt & Payri (2006, 2007). MATERIALS AND METHODS All material was collected using SCUBA, dredging, snorkelling or reef- walking. Herbarium specimens were pressed using standard techniques, and representative parts of thalli and turf algae stored in 4% buffered formalin in sealed plastic bags packed in a light-proof container for shipment and later anatomical examination in the laboratory. Herbarium specimens were photographed using a bench-mounted digital camera (NIKON Coolpix 995). Photomicrographs were obtained using OLYMPUS C-4040Z or C-5050Z digital cameras fitted on an OLYMPUS BH2 microscope. Voucher specimens are housed at the Phycological Herbarium of the Université de la Polynésie française in Tahiti (UPF), with ‘S’ referring to slide collections, and can also be viewed online at the following Internet address: http://biodiv.upf.pf/base (link at times subject to outages). ‘IFR’ refers to holdings in the herbarium of the French Institute of Research on Coral Reef Environment (IFRECOR) in Bora Bora, French Polynesia (curated by Mr. Denis Schneider). Where necessary, available French Polynesian herbarium records in UPF have been re-verified in the light of new taxonomic information, and some by William Setchell and H. E. Parks as well as other early collections in BM (British Museum,London), PC (Museum National d’Histoire Naturelle, Paris), SAP (Hokkaido University, Sapporo) and UC (University of California, Berkeley) examined either on site or on loan by the first author. Unfortunately, some voucher specimens of species from Moorea listed in Payri (1987), which contain some taxa not held at UPF, could not be located and are presumed lost. Consequently, only those records which could be confirmed on the basis of existing collections, either in UPF or elsewhere, have been included in this study. Recent new records from a deepwater survey by the authors of the island of Moorea in the context of a genetic barcoding program by the University of California Gump Research Station, have been included in this publication. The taxonomy generally follows that of Silva et al., (1987; 1996), Reviers (2003), and is updated with other sources where necessary as stated in the text. For each taxon, basionym and type locality information is provided, followed by relevant synonyms and bibliographic references (mostly restricted to those that are regional, tropical or contain pertinent diagnostic figures). Asterisks (*) indicate new records for French Polynesia. Marine algal flora of French Polynesia III. Rhodophyta 5 RESULTS AND OBSERVATIONS Key to the genera of French Polynesian Rhodophyta 1a. Thallus internally calcified, even lightly so (bubbles when tested with weak acid) ............................................................ .2 1b. Thallus totally uncalcified . .19 2a. Thallus segmented.............................................. .3 2b. Thallus unsegmented............................................ .8 3a. Thallus calcified at segment joints ......................... .Tricleocarpa 3b. Thallus uncalcified at segment joints ................................. .4 4a. Axes compressed to flattened; segments with upward-curving lobes .... .5 4b. Axes terete or compressed; segments not curving upward............. .7 5a. Thallus dichotomously branched, axes flattened, 1-6 mm wide .. Jania (in part) 5b. Thallus pinnately branched, axes compressed, 0.3-1 mm wide . .6 6a. Intergenicula 0.3-0.5 mm wide, main axes percurrent, less than 9 tiered medullary cells per intergenicula ....................... Jania (in part) 6b. Intergenicula 0.5-1 mm wide, main axes not percurrent, more than 10 tiered medullary cells per intergenicula ...................... .Corallina 7a. Axes usually terete, less than 150 µm in diameter; conceptacles located at nodes just below dichotomies ............................ Jania (in part) 7b. Axes compressed to terete, more than 500 µm in diameter; conceptacles scattered on internode surface .............................. .Amphiroa 8a. Thallus flabellate, with skin-like texture .................. .Titanophora 8b. Thallus not as above. ............................................ .9 9a. Thallus with rings of verticillate hairs around branches ........ Actinotrichia 9b. Thallus without verticillate rings of hairs around branches.............. .10 10a. Tips of ultimate branches uncalcified. .13 10b. Thallus calcified throughout, including tips ........................ .11 11a. Thallus stone-like or crustose ...................... Corallinales (in part) 11b. Thallus not stone-like or crustose................................... .12 12a. Axes rigid, sometimes villous, to 3 mm wide . .18 12b. Axes soft and gelatinous, glabrous, to 10 mm wide ............ Renouxia 13a. Cortical cells distinctly inflated or club-shaped; carpogonial branch straight, 3-celled, calcification annulate ............................. Yamadaella 13b. Cortical cells not distinctly inflated or clavate; carpogonial branch curved, 3-6-celled, calcification smooth or powdery, not annulate. .............. .14 14a. Calcification clearly restricted to axial core, surrounded by mucus; spermatangia in whorls on subapical cells, never terminal; sterile filaments issued from base of carpogonial branch making dense, non-involucral clusters below cystocarp ................................ Trichogloea 14b. Calcification diffuse, not restricted to axial core or covered by mucus; spermatangia usually terminal, not in subapical whorls; sterile filaments 6A. D. R. N’Yeurt &C. E. Payri from carpogonium either absent or making long involucres around cystocarp. .....................................................15 15a. Medullary filaments less than 30 µm in diameter, carpogonial branches lateral on subterminal cortical cells; cystocarps with long involucres of sterile filaments issued from