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Partial rbcL sequences were obtained from the type specimens of Lithophyllum coarctatum and L. gardineri. Both species were variably assigned to either Hydrolithon or Porolithon during the last two centuries, with L. coarctatum, from the tropical eastern Indian Ocean currently considered a synonym of L. gardineri from the tropical western Indian Ocean. Phylogenetic analyses show that both belong in Porolithon and that they are distinct species despite their morpho-anatomical similarities, including a columnar morphology. Porolithon epiphyticum sp. nov., from the same locality as P. coarctatum, Cocos-Keeling Islands, is the first reported epiphytic species in the genus. Eight of the currently recognized 15 species of Porolithon have had their type specimens sequenced to correctly apply names, including the generitype specimen. DNA sequencing provides independent confirmation that the morpho-anatomical character of the presence of horizontal fields of trichocytes without intervening vegetative cells is diagnostic for Porolithon. The generitypes of the four genera classified in the subfamily Metagoniolithoideae, Dawsoniolithon, Floiophycus, Harveylithon, and Metagoniolithon as well as Hydrolithon in the subfamily Hydrolithoideae, have not been sequenced. The taxonomic and nomenclatural uncertainties in each of these genera are discussed.

Species of Ulva Linnaeus are nearly impossible to identify using morpho-anatomy due to their simple thallus structure and phenotypic plasticity. The current solution to this problem is to sequence ...

Two of the four currently recognised species of Phymatolithon in South Africa are P. repandum (type locality: Half Moon Bay, Port Philip Bay, Victoria, Australia) and P. ferox (type locality: Natal, KwaZulu-Natal, South Africa). Partial rbcL sequences of the lectotype of P. repandum and the holotype of P. ferox demonstrate that the former is not present in South Africa and does not belong in Phymatolithon, whereas the latter belongs in Phymatolithon, but that the name has been misapplied in South Africa. The correct name for the species, currently called P. repandum in South Africa, is P. ferox. Partial rbcL and psbA sequences of two of the current heterotypic synonyms of P. ferox, Lithothamnion prolixum and Lithothamnion prolixum f. plicatum, show that they are conspecific and do not belong in Phymatolithon. Lithothamnion prolixum is the basionym for the species currently, but incorrectly, called P. ferox in South Africa. Phymatolithon repandum and L. prolixum belong in an as yet undescribed genus. All heterotypic synonyms of currently recognised names of non-geniculate corallines that were placed in synonymy based on morpho-anatomy should not be accepted until confirmed by DNA sequencing.

A partial rbcL sequence from the type material of Spongites discoideus from southern Argentina showed that it was distinct from rbcL sequences of South African specimens to which that name had been applied based on morpho-anatomy. A partial rbcL sequence from an original syntype specimen, herein designated the lectotype, of Lithophyllum marlothii, type locality Camps Bay, Western Cape Province, South Africa, was identical to rbcL sequences of South African field-collected specimens assigned to S. discoideus. Based on phylogenetic analyses of rbcL and/or psbA sequences, both of these species belong in Pneophyllum and are transferred there as P. discoideum comb. nov. and P. marlothii comb. nov. The two species exhibit a distinct type of development where thick, secondary, monomerous disks are produced from thin, primary, dimerous crusts. Whether this type of development represents an example of convergent evolution or is characteristic of a clade of species within Pneophyllum remains to be resolved.

Current usage of the name Ulva lactuca, the generitype of Ulva, remains uncertain. Genetic analyses were performed on the U. lactuca Linnaean holotype, the U. fasciata epitype, the U. fenestrata holotype, the U. lobata lectotype, and the U. stipitata lectotype. The U. lactuca holotype is nearly identical in rbcL sequence to the U. fasciata epitype, a warm temperate to tropical species, rather than the cold temperate species to which the name U. lactuca has generally been applied. We hypothesize that the holotype specimen of U. lactuca came from the Indo-Pacific rather than northern Europe. Our analyses indicate that U. fasciata and U. lobata are heterotypic synonyms of U. lactuca. Ulva fenestrata is the earliest name for northern hemisphere, cold temperate Atlantic and Pacific species, with U. stipitata a junior synonym. DNA sequences from type specimens provide an unequivocal method for applying names to Ulva species. This article is protected by copyright. All rights reserved.

One of the earliest described non-geniculate coralline algae from the Arctic is Kjellman’s 1877 Lithophyllum arcticum. It has been classified successively in Lithothamnion and Mesophyllum and curre...

International audience; Non‐geniculate coralline algae are difficult to identify based solely on morpho‐anatomy. To address the systematics of several taxonomically challenging taxa, we analyzed DNA sequences of a short portion (118‐296 base pairs) of the 3’ end of the rbcL gene from three type specimens. The analyses revealed that Harveylithon munitum (basionym: Lithophyllum munitum), described in 1906 from Cave Cays, Exuma Chain, Bahamas, is conspecific with both Goniolithon accretum and Goniolithon affine, described in 1906 from Sand Key, Florida and in 1907 from Culebra Island, Puerto Rico, respectively. L. munitum and G. accretum were described in the same 1906 publication and have equal priority. We have selected the currently accepted and most commonly used name H. munitum to apply to this entity. Comparative analyses of rbcL, psbA, UPA, COI, and LSU sequences from contemporary field‐collected specimens revealed that H. munitum currently inhabits mesophotic rhodolith beds in the northwestern Gulf of Mexico, as well as the intertidal zone in the Florida Keys, Honduras, Atlantic Mexico, Caribbean Panama, and Guadeloupe, French West Indies. Species delimitation analyses reveal that the Western Atlantic and Australian H. munitum populations may be separate species. Two new species of Harveylithon from the northwestern Gulf of Mexico and one new species from the southwestern Gulf of Mexico, the Caribbean, and the Red Sea were also identified in the analyses and are described.

Coralline red algae in the non-geniculate genera Clathromorphum, Phymatolithon and Lithothamnion are important benthic ecosystem engineers in the photic zone of the Arctic and Subarctic. In these regions, the systematics and biogeography of Clathromorphum and Phymatolithon have mostly been resolved whereas Lithothamnion has not, until now. Seventy-three specific and infraspecific names were given to Arctic and Subarctic Lithothamnion specimens in the late 19th and early 20th century by Frans R. Kjellman and Mikael H. Foslie. DNA sequences from 36 type specimens, five historical specimens, and an extensive sampling of recent collections resulted in the recognition of four Arctic and Subarctic Lithothamnion species, L. glaciale, L. lemoineae, L. soriferum and L. tophiforme. Three genes were sequenced, two plastid-encoded, rbcL and psbA, and the mitochondrial encoded COI-5P; rbcL and COI-5P segregated L. glaciale from L. tophiforme but psbA did not. Partial rbcL sequences obtained from type collections enabled us to correctly apply the earliest available names and to correctly place the remainder in synonymy. We were unable to sequence another 22 type specimens, but all of these are more recent names than those that are now applied. It is difficult to identify these species solely on morpho-anatomy as they can all occur as encrusting corallines or as maerl (rhodoliths). We demonstrate the importance of sequencing historical type specimens by showing that the recently proposed North-east Atlantic L. erinaceum is a synonym of one of the earliest published Arctic species of Lithothamnion, L. soriferum, itself incorrectly placed in synonymy under L. tophiforme based on morpho-anatomy. Based on sequenced specimens, we update the distributions and ecology of these species.

Although complete mitogenomic data have been widely applied in human and other animal population studies, they are extremely limited for florideophycean red algal populations. Gelidiella fanii is a recently described rhodophyte, previously misidentified as G. acerosa, a cosmopolitan agar-yielding species from tropical to subtropical waters. To decipher patterns in genetic diversity and geographic distribution for G. fanii, we obtained 10 complete mitogenomes including two outgroups, G. acerosa and G. flabella. The mitogenomes ranged in size from 25,223 bp to 25,281 bp and had 48 genes, which are similar in general structure, gene order and content, and presence of a group II intron. Phylogenomic analysis revealed that G. fanii was monophyletic and clearly separate from G. acerosa. The range of G. fanii was extended from Southeast Asia and northern Australia to Eritrea, Juan de Nova Island, and Kenya in the west, and to Hawai‘i and Tetiaroa Atoll to the east. Haplotype network analysis of cox1 revealed seven geographically structured groups: Southeast Asia, Kenya/Juan de Nova Island, Indonesia, northern Australia, the Philippines, Tetiaroa Atoll, and Hawai‘i. This regional structure has likely resulted from the separation and isolation of an ancient widespread population during the Pleistocene. This study demonstrates that mitogenome sequencing is a powerful genotyping tool for studies of genetic diversity, biogeography, and conservation of economically valuable marine algal species.

An essential suite of coral reef ecosystem engineers is coralline red algae. Among these, the smooth, encrusting Porolithon onkodes has historically been considered the most important and common reef building species worldwide. We assess P. onkodes biodiversity by performing a genomic analysis of the lectotype specimen collected in 1892 from the Tami Islands, Gulf of Huon, east of New Guinea. Comparisons of DNA sequences from the lectotype specimen to those deposited in GenBank and to newly generated sequences from both field-collected and historical specimens demonstrate that at least 20 distinct species are passing under P. onkodes. We hypothesize that there were multiple evolutionary drivers including ecophysiology, hydrodynamic regimes, and biotic interactions as well as historical biogeography, which resulted in this high diversity of smooth, encrusting Porolithon species throughout the tropics. Our results emphasize the need to document the biodiversity, ecophysiology, and habitats of these tropical, reef-building algae in light of climate change and ocean acidification.

The current identification of crustose coralline algae from North Carolina is based on a few morphoanatomical studies from the last century. We reassessed the type specimens of the two Lithophyllum species historically reported from offshore communities in North Carolina, L. intermedium with a Caribbean Sea type locality and L. subtenellum with an Atlantic southern France type locality, using scanning electron microscopy images and diagnostic rbcL sequences. Neither of the sequences generated from the type specimens matched rbcL sequences from contemporary specimens collected from subtidal North Carolina epibenthic communities. On the basis of analyses of rbcL and other loci (psbA, UPA, and COI), we instead found L. atlanticum, recently described from Brazil, and L. searlesii sp. nov. from Onslow Bay, North Carolina. These sequence data show that L. atlanticum is related to northeast Pacific species, whereas L. searlesii is related to Mediterranean species.

International audience; Lithophyllum species in the Mediterranean Sea function as algal bioconstructors, contributing to the formation of biogenic habitats such as coralligenous concretions. In such habitats, thalli of Lithophyllum, consisting of crusts or lamellae with entire or lobed margins, have been variously referred to as either one species, L. stictiforme, or two species, L. stictiforme and L. cabiochiae, in the recent literature. We investigated species diversity and phylogenetic relationships in these algae by sequencing three markers (psbA and rbcL genes, cox2,3 spacer), in conjunction with methods for algorithmic delimitation of species (ABGD and GMYC). Mediterranean subtidal Lithophyllum belong to a well‐supported lineage, hereby called the L. stictiforme complex, which also includes two species described from the Atlantic, L. lobatum and L. searlesii. Our results indicate that the L. stictiforme complex consists of at least 13 species. Among the Mediterranean species, some are widely distributed and span most of the western and central Mediterranean, whereas others appear to be restricted to specific localities. These patterns are interpreted as possibly resulting from allopatric speciation events that took place during the Messinian Salinity Crisis and subsequent glacial periods. A partial rbcL sequence from the lectotype of L. stictiforme unambiguously indicates that this name applies to the most common subtidal Lithophyllum in the central Mediterranean. We agree with recent treatments that considered L. cabiochiae and L. stictiforme conspecific. The diversity of Lithophyllum in Mediterranean coralligenous habitats has been substantially underestimated, and future work on these and other Mediterranean corallines should use identifications based on DNA sequences.

Plastid-encoded rbcL and psbA sequences from branched, Caribbean Sea Lithophyllum specimens indicate that four species are present, not one. Short (263 base pairs) rbcL sequences from an isolectotype of L. kaiseri (Gulf of Suez) and the holotypes of L. congestum, L. daedaleum and L. platyphyllum (Caribbean Sea) show that L. congestum and L. daedaleum are conspecific with L. kaiseri, the last having nomenclatural priority. Lithophyllum platyphyllum, currently considered a synonym of L. congestum, is recognised as a valid species. Lithophyllum stictaeforme, originally described from the Mediterranean Sea, is not conspecific with L. kaiseri (as L. congestum) as previously suggested. Lithophyllum neocongestum sp. nov. and L. pseudoplatyphyllum sp. nov. are proposed. Together with L. platyphyllum, these three branched species are so far endemic to the Caribbean Sea. This is the first report, documented by DNA sequence data, of a coralline species (L. kaiseri) widespread through the tropical Indo-West Pacific Oceans, Red Sea and Caribbean Sea.

The filamentous marine red alga Ceramium cimbricum was described from Denmark, but the name has since been applied to populations worldwide. To determine if C. cimbricum from the Pacific is conspecific with C. cimbricum from the Atlantic, we (1) deciphered an authentic rbcL sequence for the lectotype specimen of C. cimbricum, (2) performed phylogenetic analysis on Pacific and Atlantic C. cimbricum, and (3) assembled and analyzed the complete mitochondrial and plastid genomes of specimens of C. cimbricum from Denmark and California. The lectotype sequence of C. cimbricum was unique and fully resolved with other Atlantic Ceramium species, however, the specimens of C. cimbricum from Denmark, Norway, California, Oregon, and Korea formed a clade with Pacific species. The plastid and mitochondrial genomes of C. cimbricum from Denmark and California were similar in length and gene content, differing by only 67 SNPs and nine gaps for the plastid, and by 100 SNPs and 31 gaps for the mitochondrial genomes. These results support the continued application of the name C. cimbricum to specimens from Denmark, and warrant the naming of a new species, Ceramium sungminbooi sp. nov., native to Asia and introduced to the northeastern Pacific and Europe.

Molecular surveys are leading to the discovery of many new cryptic species of marine algae. This is particularly true for red algal intertidal species, which exhibit a high degree of morphological convergence. DNA sequencing of recent collections of Gelidium along the coast of California, USA, identified two morphologically similar entities that differed in DNA sequence from existing species. To characterize the two new species of Gelidium and to determine their evolutionary relationships to other known taxa, phylogenomic, multigene analyses, and morphological observations were performed. Three complete mitogenomes and five plastid genomes were deciphered, including those from the new species candidates and the type materials of two closely related congeners. The mitogenomes contained 45 genes and had similar lengths (24,963-24,964 bp). The plastid genomes contained 232 genes and were roughly similar in size (175,499-177,099 bp). The organellar genomes showed a high level of gene synteny. The two Gelidium species are diminutive, turf-forming, and superficially resemble several long established species from the Pacific Ocean. The phylogenomic analysis, multigene phylogeny, and morphological evidence confirms the recognition and naming of two new species, describe herein as G. gabrielsonii and G. kathyanniae. On the basis of the monophyly of G. coulteri, G. gabrielsonii, G. galapagense, and G. kathyanniae, we suggest that this lineage likely evolved in California. Organellar genomes provide a powerful tool for discovering cryptic intertidal species and they continue to improve our understanding of the evolutionary biology of red algae and the systematics of the Gelidiales.

Nothogenia fastigiata has been reported to exhibit great morphological variability and has been considered to be widely distributed in the Southern Hemisphere. To test its current circumscription, sequences from type material of N. fastigiata and other species currently synonymized with it were compared to those from recent collections of this and other species in the genus. Eight distinct species previously subsumed under the name N. fastigiata were identified. Multiple specimens from southern Chile and a single specimen from Campbell Island (subantarctic New Zealand) were conspecific with type material of N. fastigiata from the Falkland Islands. For other species, molecular analyses of recent collections using the nuclear ITS1-5.8S-ITS2 region of the ribosomal cistron, the chloroplast rbcL and psbA genes and the mitochondrial COI gene indicated a strong geographic pattern to species relationships. Other specimens identified as N. fastigiata from Chile represented up to five species, including N. chilensis and N. fragilis, based on sequences of type material; these Chilean species occurred on a monophyletic branch. We also recognized N. lingula comb. nov. from Tasmania, which is closely related to N. fastigiata, based on sequences of type material. Specimens from mainland New Zealand identified as N. fastigiata fell into a distinct clade with New Zealand N. pulvinata and represented a previously undescribed species, described here as N. neilliae sp. nov. Another New Zealand species, N. pseudosaccata, was distantly related to N. variolosa from Auckland Island and other subantarctic islands south of New Zealand. The New Zealand species were more closely related to South African N. erinacea and N. ovalis than to species of Nothogenia from Chile, including N. fastigiata, although bootstrap support for this interpretation was weak. These genetic data demonstrate that matching DNA sequences from archival Nothogenia material to modern specimens can be used to identify and define new and old cryptic species.

Interspecific systematics in the red algal order Sporolithales remains problematic. To re-evaluate its species, DNA analyses were performed on historical type material and recently collected specimens assigned to the two genera Sporolithon and Heydrichia. Partial rbcL sequences from the lectotype specimens of Sporolithon ptychoides (the generitype species) and Sporolithon molle, both from El Tor, Egypt, are exact matches to field-collected topotype specimens. Sporolithon crassum and Sporolithon erythraeum also have the same type locality; material of the former appears to no longer exist, and we were unable to PCR amplify DNA from the latter. A new species, Sporolithon eltorensis, is described from the same type locality. We have not found any morpho-anatomical characters that distinguish these three species. No sequenced specimens reported as S. ptychoides from other parts of the world represent this species, and likely reports of S. ptychoides and S. molle based on morpho-anatomy are incorrect. A partial rbcL sequence from the holotype of Sporolithon dimotum indicates it is not a synonym of S. ptychoides, and data from the holotype of S. episporum confirm its specific recognition. DNA sequences from topotype material of Heydrichia woelkerlingii, the generitype species, and isotype material of Heydrichia cerasina confirm that these are distinct species; the taxon reported to be H. woelkerlingii from New Zealand is likely an undescribed species. Type specimens of all other Sporolithon and Heydrichia species need to be sequenced to confirm that they are distinct species; morpho-anatomical studies have proved inadequate for this task.

A large number of invasive marine invertebrates are recognized from Elkhorn Slough (ES), California. One of these species in the slough is treated as Hymeniacidon sinapium (Family Halichondriidae) but its species identity is in doubt pending molecular confirmation. The purpose of this investigation was to confirm the presence of H. sinapium in ES, determine its distribution in the slough, and compare its genetic diversity to others in California and worldwide. To address these goals, 23 specimens of Hymeniacidon were analyzed using DNA sequences of the nuclear rDNA internal transcribed spacers (ITS1 + ITS2) and the 5.8S exon. The sequences were compared against those of H. sinapium from: San Diego and Tomales Bay in California; Japan; and South Korea. All ES sequences were found to be nearly identical to the other H. sinapium sequences, differing by only 1-3 nucleotides. ES specimens displayed five unique genotypes: three showed intragenomic polymorphisms (IGPs) in the ITS1 region (positions 155, 181, and 195). These data conclusively document the presence of H. sinapium in ES as well as define the species to a relatively narrow portion of its eastern shores (~4 km long). Since the genetic diversity of H. sinapium in ES is higher than that reported worldwide, its presence in ES is likely the result of multiple introductions. One of the IGPs in ES was found to be the most abundant and was widely distributed in the slough: an indication that it may be spreading.

Lindstrom S.C., Hughey J.R. and Martone P.T. 2011. New, resurrected and redefined species of Mastocarpus (Phyllophoraceae, Rhodophyta). Phycologia 50: 661–683. DOI: 10.2216/10-38.1 Recent molecular phylogenetic investigations of the red algal genus Mastocarpus from the northeast Pacific resolved numerous cryptic species. Although species were clearly defined through genetic analyses, the correct names to apply to the species remained unclear due to both morphological variability within species and morphological similarity between species. To determine the appropriate name for each entity, we analyzed DNA from type material of taxa previously ascribed to Mastocarpus. In combination with this analysis, an updated phylogeny based on a broad range of geographical and morphological collections is presented that includes data from nuclear (ribosomal internal transcribed spacers [ITS]), chloroplast (rbcL) and mitochondrial [cytochrome oxidase I (COI)] genomes. By analyzing partial ITS region sequences of type sp...

Hughey J.R. and Hommmersand M.H. 2010. A molecular study of Mazzaella (Gigartineaceae, Rhodophyta) and morphological investigation of the splendens clade from Pacific North America. Phycologia 49: 113–135. DOI: 10.2216/08-68.1 The delineation of species of Mazzaella remains problematic because of similarities in thallus shape and color. To better define species boundaries, molecular phylogenetic analyses and developmental studies of Mazzaella were performed on one of the more taxonomically challenging clades, the splendens group (Mazzaella flaccida, Mazzaella linearis, Mazzaella sanguinea and Mazzaella splendens). Using an expanded rbcL data set, internal transcribed spacer sequences, and a combined analysis, six clades were identified: splendens, californica, rosea, cobinae, oregona, and South American/African. Morphological examination of members of the splendens clade identified differences in their cystocarpic and tetrasporangial development and supported the recognition of two subspecies, M....

SUMMARY The Japanese red algaGrateloupia lanceolata (Okamura) Kawaguchi was discovered in southern California at Santa Catalina Island in spring 2003 and April 2008 and in central California at the mouth of the Elkhorn Slough in Moss Landing in May, June and July of 2008. The morphology of thalli from both localities agrees with published figures. Sequences from therbcL gene and the nuclear marker, internal transcribed spacer-1 from CalifornianG. lanceolatawere identical to those from two specimens ofG. lanceolataintroduced to the Thau Lagoon, Mediterranean France and a specimen from Japan. It is likely that the import of oysters for mariculture played a role in its introduction into California.

The field of molecular paleontology has recently made significant contributions to anthropology and biology. Hundreds of ancient DNA studies have been published, but none has targeted fossil coralline algae. Using regions of the SSU gene, we analyzed rDNA from fossil coralline algae of varying ages and states of preservation from Spain, Papua New Guinea (PNG), and the Great Barrier Reef (GBR). Specimens from PNG, GBR, and some localities from Spain did not contain endogenous ancient DNA. Reproducible sequence data were obtained from specimens ∼550 years old from near Cadiz, Spain, and from rocky-shore deposits in Carboneras, Almeria Province of Spain (∼78,000 years before present [YBP]). Based on BLAST searches and a phylogenetic analysis of sequences, an undescribed coralline alga belonging to the Melobesioideae was discovered in the Carboneras material as well as the following coralline genera: Jania, Lithophyllum, Lithothamnion, Mesophyllum, and Phymatolithon. DNA from fleshy brown and red macroalgae was also discovered in the specimens from Carboneras. The coralline algae identified using molecular techniques were in agreement with those based on morphological methods. The identified taxa are common in the present-day southeastern Spain littoral zone. Amino acid racemization, concentration ratios, and specific concentrations failed to show a correlation between biomolecular preservation and PCR amplification success. Results suggest that molecular investigations on fossil algae, although limited by technical difficulties, are feasible. Validity of our results was established using authentication criteria and a self-critical approach to compliance.

Species boundaries in the Gigartinaceae are poorly defined due to the high degree of phenotypic plasticity exhibited by the thallus, with the result that many superfluous taxa have been described. To clarify the taxonomy of species of Chondracanthus Kutzing reported from the Gulf of California and Pacific coast of North America, morphological and molecular phylogenetic studies were performed. Phylogenetic analyses of chloroplast and nuclear DNA yielded nearly congruent hypotheses. DNA from type material was examined from select species to validate the correspondence between modern and historically important collections. Monographic observations on species from Pacific North America were included to clarify species boundaries. Analyses identified two species from the Gulf of California and nine from the Pacific coast. The following statements are supported: (1) Gigartina serrata Gardner is independent of Chondracanthus canaliculatus (Harvey) Guiry, and Chondracanthus serratus (Gardner) comb. nov. ...

Next generation sequence data were generated and used to assemble the complete plastomes of the holotype of Membranoptera weeksiae, the neotype (designated here) of M. tenuis, and a specimen examined by Kylin in making the new combination M. platyphylla. The three plastomes were similar in gene content and length and showed high gene synteny to Calliarthron, Grateloupia, Sporolithon, and Vertebrata. Sequence variation in the plastome coding regions were 0.89% between M. weeksiae and M. tenuis, 5.14% between M. weeksiae and M. platyphylla, and 5.18% between M. tenuis and M. platyphylla. We were unable to decipher the complete mitogenomes of the three species due to low coverage and structural problems; however, we assembled and analyzed, the cytochrome oxidase I, II, and III loci and found that M. weeksiae and M. tenuis differed in sequence by 1.3%, M. weeksiae and M. platyphylla by 8.4%, and M. tenuis and M. platyphylla by 8.1%. Evaluation of standard marker genes indicated that sequences from the rbcL, RuBisCO spacer, and CO1 genes closely approximated the pairwise genetic distances observed between the plastomes of the three species of Membranoptera. A phylogenetic tree based on rbcL sequences showed that M. tenuis and M. weeksiae were sister taxa. Short rbcL sequences were obtained from type specimens of M. dimorpha, M. multiramosa, and M. edentata and confirmed their conspecificity with M. platyphylla. The data support the recognition of three species of Membranoptera occurring south of Alaska: M. platyphylla, M. tenuis, and M. weeksiae. This article is protected by copyright. All rights reserved.

Uncertainties about the identity of type specimens of red algae have frequently led to taxonomic and nomenclatural confusion. A procedure for extracting PCR-amplifiable DNA from formalin-fixed material and herbarium specimens was used to investigate the taxonomic status of several South African Gigartinaceae. We compared nucleotide sequences in the internal transcribed spacer 1 (ITS1) region in type specimens and other historically important collections presently referred to Gigartina bracteata, G. radula and G. stiriata. The following opinions are supported: (1) Fucus bracteatus S.G. Gmelin, Chondrodictyon capense Kutzing and Iridaea clathrata Decaisne represent a single species of South African Gigartina (G. bracteata (S.G. Gmelin) Setchell & Gardner) in which the disintegration of tetrasporangial sori results in a reticulate thallus. (2) Mastocarpus polycarpus Kutzing, M. incrassatus Kutzing and Iridaea lapathifolia Kutzing represent a single species of South African Gigartina (G. polycarpa (Kutzing) Setchell & Gardner) that has often, but erroneously, been called G. radula (Esper) J. Agardh. (3) Mastocarpus verrucosus Kutzing is a later heterotypic synonym of Iridaea papillosa Bory (Sarcothalia papillosa (Bory) Leister) and was based on material that probably came from southern South America rather than from South Africa, the provenance given by Kutzing. (4) Fucus stiriatus Turner and Sphaerococcus burmannii C. Agardh represent a single species of South African Sarcothalia (S. stiriata (Turner) Leister).

Molecular data obtained by a procedure for extracting PCR-amplifiable nuclear and chloroplast DNA from old and formalin-fixed red algal herbarium specimens were used to elucidate problems in the systematics of Pacific Gigartinaceae. Correspondence between nucleotide sequences of the internal transcribed spacer 1 region or the RUBISCO spacer from type specimens and modern collections supports the following conclusions. (1) The type of Fucus cordatus Turner, now Iridaea cordata (Turner) Bory, came from the southern hemisphere (probably from Isla de los Estados, Argentina) rather than from Banks Island, B.C., Canada. (2) The type of Iridaea heterocarpa P. et R. [ Mazzaella heterocarpa (P. et R.) Fred.] represents the tetrasporangial phase of a species of Chondrus , possibly C. crispus Stackh. (3) The types of Iridaea lilacina P. et R., I. phyllocarpa P. et R., and Iridophycus furcatum S. et G. represent a single species from Alaska, Mazzaella phyllocarpa (P. et R.) Perest., currently but incorrectly called M. heterocarpa. (4) The type of Iridophycus oregonum Doty represents the tetrasporangial phase of the species from southern Alaska to southern California known incorrectly as M. heterocarpa . (5) Mazzaella splendens (S. et G.) Fred. is more closely related to M. linearis (S. et G.) Fred. than it is to M. flaccida (S. et G.) Fred. (6) Iridophycus coriaceum S. et G. is conspecific with M. splendens , whereas Rhodoglossum coriaceum E.Y. Dawson is an independent species: Mazzaella coriacea (E.Y. Dawson) Hughey. (7) Iridaea cornucopiae P. et R. is conspecific with Mazzaella laminarioides (Bory) Fred., and the type probably came from Chile rather than from the North Pacific. (8) Plants attributed to Iridaea cornucopiae in Pacific North America are referable to Mazzaella parksii (S. et G.) comb. nov. (9) Rhodoglossum parvum G. M. Smith et Hollenb. is an independent species: Mazzaella parva (G. M. Smith et Hollenb.) comb. nov. (10) Grateloupia squarrulosa S. et G., Grateloupia johnstonii S. et G., and Gigartina pectinata E.Y. Dawson represent a single species: Chondracanthus squarrulosus (S. et G.) comb. nov.

Greater than 50 species of Gigartinaceae have been described from Pacific North America, about half of which are currently recognized. Although the family is treated extensively in the taxonomic literature, many of the species are still confused and a comprehensive revision is required. We sequenced the rbcL (RuBisCO) gene and ITS (Internal Transcribed Spacer) 1, 2, and 5.8S regions from a large number of recent collections and identified a discrete of number data sets. These were analysed in comparison with the morphological evidence for each of the taxa. Uncertain of the possibility that our operational taxonomic units may not correspond to the types, we developed a protocol for isolating PCR-friendly DNA from herbarium specimens, some reaching back as far as 1670. The DNA profiles of types and historically important specimens were compared to those for recently collected silica gel-dried and formalin-fixed material and assigned correct names. Species studied ranged from Alaska to Mexico and the Gulf of California and were compared to outgroup taxa from Pacific South America and the Southern Ocean. Particular attention was paid to variations in morphology as they relate to habitat with emphasis on the presence or absence of different morphological forms among sympatric and allopatric populations. We recognize 10 species in Chondracanthus (including one new combination and one new species) and 16 species in Mazzaella (including two new combinations and two new species). Finally, we tested a phylogenetic hypothesis inferred for the Gigartinaceae from rbcL sequences for congruence with one generated from ITS sequences.