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Bernabé Santelices - One of the best experts on this subject based on the ideXlab platform.

  • Taxonomic review of the species of Pterocladia (Gelidiales, Rhodophyta)
    Journal of Applied Phycology, 1998
    Co-Authors: Bernabé Santelices
    Abstract:

    Segregating Pterocladiella from Pterocladia stimulated new taxonomic studies of the species originally assigned to Pterocladia. A total of 28 species are ascribed to the genus, one of them with doubts. Thirteen of the 27 names are synonyms. Three of the remaining 14 species belong with Gelidium, including G. americanum, G. mcnabbianum (Dawson) comb. nov. and G. musciformis. Seven other species belong with Pterocladiella, including P. bartlettii (Taylor) comb. nov., P. bulbosa, P. caerulescens, P. caespitosa (Kylin) comb. nov., P. caloglossoides (Howe) comb. nov., P. capillacea and P. melanoidea. Two species are retained in Pterocladia, the type P. lucida and P. rectangularis. Two others, P. heteroplatos and P. media are placed in incertae sedis as additional studies of fertile materials are needed to determine their generic status. The genus Pterocladia now appears to include two large-sized species restricted to Australia-New Zealand. Pterocladiella has 8 small-sized species (including P. minima), mainly inhabiting tropical and subtropical waters. Future research documenting sexual reproduction in Gelidiella and solving the presently recognized heterogeneity in Gelidium will help to trace the relationships between Pterocladiella and these two genera.

  • Pterocladiella, a new genus in the Gelidiaceae (Gelidiales, Rhodophyta)
    Phycologia, 1997
    Co-Authors: Bernabé Santelices, Max H. Hommersand
    Abstract:

    Abstract A new genus of marine red algae, Pterocladiella (Gelidiales), is proposed to accommodate those species previously assigned to Pterocladia that have the following features: intercalary carpogonia directed toward both surfaces of the thallus, nutritive filaments growing centripetally and forming a virtually solid cylinder around the central axis, and cystocarps usually attached to one side of the cystocarp floor with chains of carposporangia on the remaining three sides. The type species is Pterocladiella capillacea (Gmelin) comb. nov. (basionym: Fucus capillaceus Gmelin). Three other nomenclatural combinations are proposed: P. caerulescens (basionym: Gelidium caerulescens Kutzing), P. melanoidea (basionym: Gelidium melanoideum Schousboe ex Bornet), and P. minima (basionym: Gelidiella minima Guiry et Womersley).

  • Medullary structure differences in Gelidium and Pterocladia (Gelidiales, Rhodophyceae): Taxonomic meaning
    Phycological Research, 1996
    Co-Authors: Dení Rodríguez, Bernabé Santelices
    Abstract:

    SUMMARY Study of the apical portions of vegetative thalli of 21 species of the genera Gelidium and Pterocladia (Gelidiales-Rhodophyta) revealed the existence of six patterns of medullary structure. Each pattern is characterized by the organization of the medullary tissue and the changes in cellular dimensions from apex to subapex. These characters can be used to separate groups of species within each genus.

  • New and old problems in the taxonomy of the Gelidiales (Rhodophyta)
    Thirteenth International Seaweed Symposium, 1990
    Co-Authors: Bernabé Santelices
    Abstract:

    The order Gelidiales includes over 140 agar-producing taxa. Many species are taxonomically confused; the boundaries of one family and all but four genera recently have been contested, and the controversy over ordinal status has lasted for over 25 years. This study reviews recent developments in the taxonomy of the group and suggests future areas for studies. The order cannot be defined by a few exclusive characters, as intended in the past, but it shows a unique combination of characters. Additional studies on Gelidiella and Acanthopeltis seem advisable to clarify family limits. The segregation of Onikusa and Pterocladiastrum is doubtful. Only three of six characters discriminate Gelidium from Pterocladia. None allows complete generic segregation and all need variability studies. Analysis of nomenclatural types in the light of morphological variation would permit an understanding of species limits in Gelidium and Pterocladia. Similar studies are needed in Gelidiella and Ptilophora.

A. J. Curtius - One of the best experts on this subject based on the ideXlab platform.

  • Local and temporal variations in essential elements and agar of the marine algaePterocladia capillacea
    Hydrobiologia, 1990
    Co-Authors: A. L. M. Geyer, J. C. Moreira, J. F. Faigle, R. E. Bruns, A. J. Curtius
    Abstract:

    The concentrations of B, Ca, Co, Cu, Fe, K, Mg, Mn, Na, P, Zn and agar were determined in samples of the red alga, Pterocladia capillacea , collected during one year in three distinct locations having different hydrologic characteristics, close to the city of Arraial do Cabo, Rio de Janeiro, Brazil. Pattern recognition methods showed that, although these concentrations are subject to temporal variations, they are more dependent on the location from which the samples were collected. Algae from locations with high human activity were richer in P, B, Co, Zn and agar than those from other locations.

  • Local and temporal variations in essential elements and agar of the marine algae Pterocladia capillacea
    Hydrobiologia, 1990
    Co-Authors: A. L. M. Geyer, J. C. Moreira, J. F. Faigle, R. E. Bruns, A. J. Curtius
    Abstract:

    The concentrations of B, Ca, Co, Cu, Fe, K, Mg, Mn, Na, P, Zn and agar were determined in samples of the red alga,Pterocladia capillacea, collected during one year in three distinct locations having different hydrologic characteristics, close to the city of Arraial do Cabo, Rio de Janeiro, Brazil. Pattern recognition methods showed that, although these concentrations are subject to temporal variations, they are more dependent on the location from which the samples were collected. Algae from locations with high human activity were richer in P, B, Co, Zn and agar than those from other locations.

J. Craig Bailey - One of the best experts on this subject based on the ideXlab platform.

  • A multigene phylogeny of the Gelidiales including nuclear large-subunit rRNA sequence data
    Journal of Applied Phycology, 1998
    Co-Authors: D. Wilson Freshwater, J. Craig Bailey
    Abstract:

    Partial sequences (1032 bp) of the nuclear-encoded large ribosomal RNA gene (LSU) were determined for 16 gelidialean species, and analyzed separately and in combination with plastid rbcL and nuclear SSU gene sequences. The number of informative characters and levels of sequence divergence among taxa are intermediate in LSU sequences as compared to that for rbcL and SSU. Analyses of the separate LSU, and a combined LSU, SSU, and rbcL data sets have identified early-diverging lineages within the Gelidiales including Gelidiella, Pterocladia, Pterocladiella, and a lineage including Gelidium and species classified in other genera. The relationships among most gelidialean taxa are well-resolved and well-supported by analyses of the combined data; however, the relationships of Ptilophora and Capreolia remain unclear. It is speculated that these two lineages have diverged from a common ancestor over an evolutionarily short period of time.

D. Wilson Freshwater - One of the best experts on this subject based on the ideXlab platform.

  • Morphology and molecular phylogeny of the marine algal order Gelidiales (Rhodophyta) from New South Wales, including Lord Howe and Norfolk Islands
    Australian Systematic Botany, 2005
    Co-Authors: Alan J. K. Millar, D. Wilson Freshwater
    Abstract:

    Fifteen species in seven genera of the marine benthic red algal order Gelidiales are reported from the New South Wales coast including Lord Howe Island and Norfolk Island. Critical sampling, a re-examination of herbarium specimens filed in the Royal Botanic Gardens Sydney and the University of Melbourne, and molecular sequencing of most of the species has determined that many of the previous identifications from this region of the Pacific were incorrect. Gelidium pusillum (Stackhouse) Le Jolis, once widely reported from this coast, is shown not to occur here and the specimens on which these misidentifications were made have proved to represent either new species or previously described species. Similarly, records of Gelidium australe J. Agardh have been found to represent misidentification of the formerly New Zealand endemic Gelidium allanii V.J.Chapman, and specimens identified as Gelidium caulacantheum J. Agardh actually represent the new species Gelidium hommersandii sp. nov. Previously recorded species verified in this study are Capreolia implexa Guiry & Womersley, Gelidiella acerosa (Forsskal) Feldmann & G.Hamel, Gelidium maidenii Lucas, Pterocladia lucida (Turner) J. Agardh, Pterocladiella caerulescens (Kutzing) Santelices & Hommersand [as Pterocladia caerulescens (Kutzing) Santelices], Pterocladiella capillacea (Gmelin) Santelices & Hommersand [as Pterocladia capillacea (Gmelin) Bornet], and Ptilophora pectinata (A. & E.S. Gepp) R.E.Norris. These species are described and illustrated in detail along with previously unreported reproductive structures. Three species are newly recorded for the New South Wales mainland [Parviphycus antipae Celan, Gelidium crinale (Turner) Gaillon, and Pterocladiella caloglossoides (Howe) Santelices], and two species (Gelidium isabelae W.R.Taylor and Gelidium allanii V.J.Chapman) represent new records for the Australian continent. In addition, three new species are described: Gelidium bernabei sp. nov., Gelidium declerckii sp. nov., and Gelidium hommersandii sp. nov.

  • A multigene phylogeny of the Gelidiales including nuclear large-subunit rRNA sequence data
    Journal of Applied Phycology, 1998
    Co-Authors: D. Wilson Freshwater, J. Craig Bailey
    Abstract:

    Partial sequences (1032 bp) of the nuclear-encoded large ribosomal RNA gene (LSU) were determined for 16 gelidialean species, and analyzed separately and in combination with plastid rbcL and nuclear SSU gene sequences. The number of informative characters and levels of sequence divergence among taxa are intermediate in LSU sequences as compared to that for rbcL and SSU. Analyses of the separate LSU, and a combined LSU, SSU, and rbcL data sets have identified early-diverging lineages within the Gelidiales including Gelidiella, Pterocladia, Pterocladiella, and a lineage including Gelidium and species classified in other genera. The relationships among most gelidialean taxa are well-resolved and well-supported by analyses of the combined data; however, the relationships of Ptilophora and Capreolia remain unclear. It is speculated that these two lineages have diverged from a common ancestor over an evolutionarily short period of time.

  • A MOLECULAR PHYLOGENY OF THE GELIDIALES (RHODOPHYTA) BASED ON ANALYSIS OF PLASTID rbcL NUCLEOTIDE SEQUENCES1
    Journal of Phycology, 1995
    Co-Authors: D. Wilson Freshwater, Suzanne Fredericq, Max H. Hommersand
    Abstract:

    Parsimony analyses of rbcL nucleotide. sequences were used to develop hypotheses of relationships among taxa in the taxonomically difficult order Celidiales including species from seven currently recognized genera: Capreolia, Gelidiella, Gelidium, Onikusa, Pterocladia, Ptilophora, and Suhria. Nucleotide. sequences of rbcL from red algae are variable and provide a large number of informative characters for phylogenetic analysis, yet the absence of insertion/deletion mutations allows for the unambiguous alignment of sequences. Species were resolved into 10 well-.supported major clades representing genera and species complexes. The topological positions of these 10 clades within trees are also well supported and indicate that Gelidium and Pterocladia as currently circumscribed are not monophyletic. These results call for a revision of the classification of the Gelidiales.

B. Santelices - One of the best experts on this subject based on the ideXlab platform.

  • Spermatangial sori on cystocarpic branchlets of species of Gelidium and Pterocladia (Gelidiales, Rhodophyta)
    Phycologia, 1995
    Co-Authors: B. Santelices, V. Flores
    Abstract:

    Fertile female gametophytes of species of Gelidium and Ptero­ cladia are found more frequently than male gametophytes (see Santelices 1988 for review). Since all of these species are assumed to be dioecious, this unequal field representation has usually been explained by faulty sampling. Detecting fertile male thalli requires microscopic examination (e.g. Akatsuka 1970, 1973, 1979), a practice infrequently done during routine field collecting. However, G. vagum has been found to be monoecious (Renfrew et al. 1989), with spermatangial patches and carpogonia occurring on the same branchlet. Using fertile specimens of Gelidium and Pterocladia, we have evaluated this situation to see if it is common among species of these two genera.

  • Intrageneric differences in cystocarp structure in Gelidium and Pterocladia
    Hydrobiologia, 1991
    Co-Authors: B. Santelices
    Abstract:

    Unilocular cystocarps, with ostioles opening to one frond surface, have traditionally distinguished Pterocladia from Gelidium , described as having bilocular cystocarps, with ostioles opening to both surfaces; however, unequally developed locules have been described in Pterocladia and differences in cystocarpic architecture between Pterocladia capillacea and the type species of the genus, P. lucida , have been recently found. As heterogeneity in cystocarp architecture raises questions of basic intergeneric distinction, a survey of reproductive morphology of species in both genera is presented in this study. Six morphologically-different types of cystocarps are distinguished among the five species of Pterocladia and the seven species of Gelidium examined.