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The existence of massive cryptic diversity in algae makes linking DNA-based lineages to existing taxa exceedingly difficult. A better integration of historical collections into modern taxonomic research is therefore highly desirable. Using the brown, algal genus Lobophora as a test case, we explore the feasibility of linking taxonomic names to clades in modern phylogenies. Despite Lobophora being a pantropical genus with probably more than 100 species, traditionally only a handful of species have been recognized. In this study we reevaluated the identity of 17 historical taxa thought to belong to Lobophora by attempting DNA amplification of herbarium material as well as specimens recently collected from the type localities (epitypes). In an attempt to assign them to Molecular Operational Taxonomic Units, the obtained sequences were integrated in a global Lobophora phylogeny based upon data derived from more than 650 specimens. Our results indicate that although five sequences were obtained from type specimens, exclusive reliance on information preserved in type specimens is problematic. Epitype material proved a more successful way forward, but this route often comes with a considerable degree of uncertainty, especially in tropical regions where the extent of sympatry among Lobophora lineages is often considerable. More problematic from a broader perspective is the fact that for 35% of historical taxa, either the type could not be traced or permission was not granted to extract DNA from the types. Such a low accessibility rate may reduce our reliance on type material and jeopardize future efforts to integrate historical taxa into a framework of a modern DNA-based taxonomy.

Gibsmithia hawaiiensis is a peculiar red alga characterized by furry gelatinous lobes arising from a cartilaginous stalk. The species has been recorded from tropical reef systems throughout the Indo-Pacific. A multilocus phylogeny (UPA, rbcL, COI-5P) of 36 specimens collected throughout the species distribution range, showed high genetic diversity at species level. Two major groups were identified, each consisting of multiple lineages. Genetic variability was low in the Hawaiian Islands and the northern Red Sea and high in the Western Indian Ocean and the Coral Triangle, where lineages overlap in distribution. Genetic distances suggest that G. hawaiiensis represents a complex of five cryptic species, with no difference observed in the external morphology corresponding to separate lineages. Anatomical and reproductive differences were observed at the microscopic level for the lineage from the Red Sea, which is here described as G. eilatensis sp. nov. The geographic range of the species complex is here expanded to include Madagascar, the Red Sea and the Indo-Malay region, and the generitype seems endemic to the Hawaiian Islands. Algal diversity on coral reef systems is discussed from a conservation perspective using G. hawaiiensis as an example.

Molecular characterization (plastid-encoded tufA gene) of New Caledonian members of the Caulerpa racemosa–Caulerpa peltata complex identified five lineages, each possibly harboring multiple species-level entities. On a global scale, the complex encompassed six lineages, two of which were pantropical and the remainder seemingly were restricted to the Indo-Pacific basin. Caulerpa racemosa var. cylindracea, a fast-spreading introduced taxon in the Mediterranean Sea and the Canary Islands, was previously thought to be restricted to southwestern Australia; it was newly reported here for New Caledonia and several northern Australian locations, including the Great Barrier Reef.

An examination of a series of collections from the coast of Natal, South Africa, has revealed the presence of two species of Martensia C. Hering nom. cons: M. elegans C. Hering 1841, the type species, and an undescribed species, M. natalensis sp. nov. The two are similar in gross morphology, with both having the network arranged in a single band, and with reproductive thalli of M. elegans usually larger and more robust than those of M. natalensis. Molecular studies based on rbcL sequence analyses place the two in separate, strongly supported clades. The first assemblage occurs primarily in the Indo-West Pacific Ocean, and the second is widely distributed in tropical and warm-temperate waters. Criteria that have been used in the past for separating the two, namely, the number and shape of the blades, the presence of a single- versus a multiple-banded network, and blade margins entire or toothed, were determined to be unreliable. Although the examination of additional species is required, the morphology and position of procarps and cystocarps, whether at or near the corners of the longitudinal lamellae and the cross-connecting strands or along the lobed, membranous edges of the longitudinal lamellae or on the thallus margins, may prove to be diagnostic at the subgenus level. We recognize subg. Martensia, including the type of Martensia: M. elegans and subg. Mesotrema (J. Agardh) De Toni based on Martensia pavonia (J. Agardh) J. Agardh.

Grateloupia filicina (C. Agardh) Lamouroux, originally described from the Mediterranean Sea, has long been considered a textbook example of a marine red alga with a cosmopolitan distribution. An rbcL-based molecular phylogeny, encompassing samples covering the entire geographic distribution of the species, revealed a plethora of ‘‘cryptic’’ species, whereby the presence of genuine G. filicina is limited to the Mediterranean basin. The phylogeny revealed a strong biogeographic imprint, with specimens from temperate regions resolved in clades composed of species inhabiting the same geographic region. Presence of widely divergent morphologies in the temperate clades indicated that several lineages have converged independently to a G. filicina-type morphology. Tropical representatives are resolved in a single clade with very uniform G. filicina-type morphology and pairwise sequence divergences that are lower than the average divergence observed in temperate lineages. This, combined with a lack of clear geographic structure among the tropical lineages, may indicate a more recent divergence with long-range dispersal capacities. Violations to the biogeographic signal in temperate lineages seemed to be due to either inadequate taxonomy or recent introductions. Grateloupia minima P. & H. Crouan, a taxon placed in synonymy under G. filicina, is reinstated as a separate species distributed in the northeast Atlantic Ocean. Grateloupia capensis sp. nov. is described to accommodate specimens from South Africa with a G. filicina-type morphology, and G. filicina var. luxurians is elevated to species status. Morphological and anatomical characters were put forward that support the distinctiveness of these three distinct species.

A systematic reassessment of the sole representative of the South African genus Phyllymenia, P. belangeri, indicates a lack of clear-cut diagnostic characters to separate it from Grateloupia. The morphology of the auxiliary cell ampullae, widely regarded as a key generic character in the Halymeniaceae, is almost identical in both genera. The autapomorphic character that has traditionally separated Phyllymenia from Grateloupia is the formation of pronounced lateral cytoplasmic protuberances on inner cortical cells. However, the establishment of protuberances is correlated with the presence of large intercellular spaces between neighbouring cortical cell files, coupled with narrow intercalary cortical cells. Thus, in order to establish secondary pit connections to more distant neighbouring cells, cortical cell protuberances may have become more prominent in P. belangeri than in species of Grateloupia with smaller intercellular spaces. Phylogenetic analyses of chloroplast-encoded rbcL sequences for a dataset including four representatives of P. belangeri and 32 other species, currently placed in Grateloupia or Prionitis, resolve (with high support) P. belangeri as a sister taxon of G. longifolia from South Africa. Based on morphological and molecular evidence, it is therefore proposed that Phyllymenia be reduced to a synonym of Grateloupia.

61st Annual Meeting of the Phycological Society of America. Warwick, Rhode Island, EUA, 5-9 de Agosto.

The red algal genus Predaea (Rhodophyta, Nemastomataceae, Nemastomatales) currently comprises 20 species found in tropical to temperate waters worldwide. The species going under the name Predaea feldmannii (Nemastomataceae, Nemastomatales) in the Azores is here reduced to subspecies rank as P. feldmannii subsp. azorica on the basis of comparative morphology and rbcL sequence analysis. The evidence presented here includes a phylogenetic tree inferred from chloroplast-encoded rbcL sequences of selected members of the Nemastomatales. P. feldmannii subsp. azorica shares with P. feldmannii subsp. feldmannii linear-oblong outer cortical cells, dichotomously branched cortical fascicles, a large number of auxiliary nutritive cells per cluster, and gonimoblast initiation from the incoming connecting filament near its point of fusion with the auxiliary cell. Differences include a sac-like, lobed thallus and occasional lateral cells on the carpogonial branch in the Azorean subspecies, versus a subcylindrical, subdichotomous habit with marginal lobes, and lack of lateral cells on the carpogonial branch in P. feldmannii subsp. feldmannii. The known distribution of P. feldmannii subsp. feldmannii is worldwide in tropical regions and so far P. feldmannii subsp. azorica is known only from the Azores. RÉSUMÉ: Le genre d'algues rouges Predaea (Rhodophyta, Nemastomatacées, Nemastomatales) comporte actuellement 20 espèces habitant les mers tropicales et tempérées du monde entier. L'espèce connue sous le nom de Predaea feldmannii aux Açores est réduite ici au rang d'une sous-espèce, P. feldmannii subsp. azorica, sur la base de l'analyse morphologique comparative et le séquençage du gène rbcL. Les données présentées ici incluent un arbre phylogénétique des séquences rbcL, qui montre la position évolutive de l'espèce des Açores par rapport à celles d'autres régions. P. feldmannii sous-espèce azorica est caractérisé, comme la sous-espèce P. feldmannii subsp. feldmannii, par des cellules corticales externes linéaires-oblongues, des fascicules corticaux dichotomes, un grand nombre de cellules nutritives auxiliaires, et le développement du gonimoblaste à partir du filament de connexion près du point de fusion avec la cellule auxiliaire. Les différences pour la sous-espèce açoréenne incluent un thalle lobé et en forme de sac, un rameau carpogonial occasionnellement portant des cellules latérales, vis-à-vis d'un thalle subcylindrique et subdichotome avec lobes marginaux ; pour P. feldmannii subsp. feldmannii, l'absence de cellules latérales sur la rameau carpogonial.