Showing papers in "Phycologia in 1995"
220 citations
TL;DR: This data indicates that the dispersal routes of the toxic dinoflagellates Alexandrium tamarense and A. catenella have changed during the course of their evolutionary history and are likely to have changed since the discovery of E. coli.
Abstract: Hypotheses concerning the molecular evolution, population structure and dispersal of the toxic dinoflagellates Alexandrium tamarense (Lebour) Balech, A. catenella (Whedon et Kofoid) Balech and A. f...
190 citations
TL;DR: A new picoplanktonic alga, Ostreococcus tauri Courties et Chretiennot-Dinet, gen. et sp.
Abstract: A new picoplanktonic alga, Ostreococcus tauri Courties et Chretiennot-Dinet, gen. et sp. nov. (Chlorophyta, Prasinophyceae) is described from the Thau Lagoon on the Mediterranean coast, France. Almost undetectable by light or fluorescence microscopy in field studies, the cells were discovered by their flow cytometric signature and appeared numerically as the main component of the phytoplankton. Their ultrastructure is described, with additional information on cell size, pigment and DNA content. Each cell contains a nucleus, a chloroplast, one mitochondrion, one Golgi body and a very reduced cytoplasmic compartment. A starch granule and Chi a and b demonstrate its affinity to the Chlorophyta and the presence of a Chi c-like pigment, Mg 3,8 DVP (=Mg 2,4 DVP) argues for placing it in the Prasinophyceae. It differs from other coccoid taxa in ultrastructural details, mode of division and detailed pigment composition. The size and DNA content make Ostreococcus tauri the smallest eucaryote known.
151 citations
TL;DR: The biomass and percentage cover of subtidal macro algae were recorded at five sites near Anvers Island, along the Antarctic Peninsula, in 1989 and the largest biomass contributors were the large overstory brown algae (Phaeophyceae) Desmarestia antarctica and Himantothallus grandifolius (Skottsberg) Zinova.
Abstract: The biomass and percentage cover of subtidal macro algae were recorded at five sites near Anvers Island, along the Antarctic Peninsula (64°S, 64°W) in 1989. Total macroalgal wet biomass ranged from 1.64 to 6.34 kg m−2. The largest biomass contributors were the large overstory brown algae (Phaeophyceae) Desmarestia antarctica Moe et Silva, Desmarestia menziesii J. Agardh, Desmarestia anceps Montagne and Himantothallus grandifolius (Skottsberg) Zinova. These species had an overall cover of 72% of the bottom. D. menziesii and/or D. anceps were dominant at 2 and 5 m. D. antarctica dominated the overstory at 10 and 15 m. H. grandifolius was also abundant at 15 m and dominated at 20 m. Several red macroalgae (Rhodophyta) were also conspicuous: Iridaea cordata (Turner) Bory and Curdiea racovitzae Hariot at 2 and 5 m; Myriogramme mangini (Gain) Skottsberg and Plocamium cartilagineum (Linnaeus) Dixon at 10 and 15 m; and Gigartina skottsbergii Setchell et Gardner and Sarcodia montagneana (Hooker et Harvey)...
112 citations
TL;DR: A new method that uses the fluorochrome primuline and epifluorescence microscopy for precise enumeration of dinoflagellate cysts in natural sediments in Hiroshima Bay sediments proves superior to all other dyes examined, providing higher counts of cysts.
Abstract: A new method is described that uses the fluorochrome primuline and epifluorescence microscopy for precise enumeration of dinoflagellate cysts in natural sediments. Alexandrium tamarense (Lebour) Balech resting cysts obtained in laboratory culture were fixed with glutaraldehyde and treated with methanol. The cysts were stained using nine fluorochromes under identical procedures to find those suitable for enumerating cysts. Four fiuorochromes, acriflavine, calcofluor white M2R, nile red and primuline, were found to provide satisfactory results in terms of high stainability and fluorescence intensity. Methanol treatment after fixation was necessary for high stainability. The four fluorochromes were then examined for their applicability to enumerate naturally occurring cysts in Hiroshima Bay sediments. Primuline proved to be superior to all other dyes examined, providing higher counts of cysts. Primuline-stained cysts exhibited an intense yellow-green fluorescence under blue-light excitation which hi...
108 citations
TL;DR: Two terete species of gracilarioid algae are described for the British Isles, including field characters and new details of vegetative and cystocarp structure obtained by sectioning in standard planes, using metachromatic dyes.
Abstract: Two terete species of gracilarioid algae are described for the British Isles. Gracilaria gracilis comb. nov. and Gracilariopsis longissima comb. nov. (Gracilariopsis verrucosa nom. rej. prop.) are superficially similar species long confused under the name Gracilaria verrucosa (Hudson) Papenfuss (= G. confervoides (Stackhouse) Greville), until recently regarded as the type species of the genus Gracilaria Greville. They occur regularly on southern British coasts, often in the same locality, both inter- and subtidally. Gracilariopsis longissima is also recorded for the first time from France and Spain. A lectotype is selected for Gracilaria gracilis, Gracilariopsis longissima is neotypified, and new descriptions are given, including field characters and new details of vegetative and cystocarp structure obtained by sectioning in standard planes, using metachromatic dyes. The British record for Gracilariopsis lemaneiformis (Bory) Dawson, Acleto et Foldvik is not confirmed. Revision of those definition...
79 citations
TL;DR: Small cells are observed in dense populations of many dinoflagellatespecies, both in clonal cultures and in natural bloom populations, and may become the dominant form in cultures when nutrients are exhausted.
Abstract: Small cells are observed in dense populations of many dinoflagellatespecies, both in clonal cultures and in natural bloom populations. They range in size from 0.5 to 0.16 of the normal cell volume and have reduced nucleus and cytoplasmic components. Two possible origins are considered for such small cells: unequal cell division or budding-like division, and successive ‘depauperating’ cell divisions. Small cells, which are reported here for 34 species, can proliferate actively in the late stages of exponential growth, and may become the dominant form in cultures when nutrients are exhausted. When new nutrients are added to the exhausted growth medium, small cells increase in size and structural components, and may give rise to forms of a more typical size. Small cells may also serve as gametes. In the sexual cycle of the species studied here, gametes were morphologically indistinguishable from vegetative small cells. Fusion was isogamous in Gymnodinium splendens Lebour, Gyrodinium instriatum Freud...
66 citations
TL;DR: In the northern Baltic it forms organic cysts, and an extension of the generic boundary of Scrippsiella is discussed, to include species with non-calcareous cysts.
Abstract: Scrippsiella hangoei (Schiller) comb. nov. is one of the most abundant species during the winter–spring season in the northern Baltic Sea. It has formed blooms under the ice on several occasions with cell concentrations reaching 24 × 1061−1. The species is described by light and scanning electron microscopy and shown to be identical to Peridinium gracile Lindemann 1924, nom. illeg. The plate formula is pp, vap or X, 4′, 3(4)a, 7″, 6c, 7s, 5′″, Op, 2″ ″ In the northern Baltic it forms organic cysts, and an extension of the generic boundary of Scrippsiella is discussed, to include species with non-calcareous cysts.
65 citations
60 citations
TL;DR: A new chain-forming dinoflagellate Gyrodinium impudicum sp.
Abstract: A new chain-forming dinoflagellate Gyrodinium impudicum sp. nov., Gymnodiniaceae, is described from Valencia Harbour, Ria de Vigo (Spain) and Fusaro Lagoon (Italy). The cingulum is a descending left spiral, displaced between 1/3–1/4 of the total length of the cell and the sulcus is without torsion, two reasons why the new species is assigned to Gyrodinium. This red tide organism has been misidentified in several previous papers as Gymnodinium catenatum Graham or Polykrikos schwartzii Butschli. It differs from G. calenatum in cell shape and size of the acrobase. No paralytic shellfish poison (PSP) was found. G. impudicum has caused blooms in several areas but no associated harmful effects have been reported.
56 citations
TL;DR: Analytical analysis of the thecal plate pattern in Katodinium rotundatum (Lohmann) Loeblich has revealed that the tabulation is identical to that of Heterocapsa Stein, and it is indicated that scale morphology is superior to thecal Plate pattern for identification of Hetersons species and should be included in future diagnoses of them.
Abstract: Analysis of the thecal plate pattern in Katodinium rotundatum (Lohmann) Loeblich has revealed that the tabulation is identical to that of Heterocapsa Stein. Other similarities between Katodinium rotundatum and Heterocapsa include the presence of triangular scales on the cell surface, the pyrenoid structure and the structure of the flagellar apparatus. Katodinium rotundatum is transferred to Heterocapsa as this name has priority. It is indicated that scale morphology is superior to thecal plate pattern for identification of Heterocapsa species and should be included in future diagnoses of them. The organism described as Heterocapsa quadridentata Stein is transferred to Peridinium, as Peridinium quadridentata (Stein) comb. nov.
TL;DR: Alexandrium pseudogonyaulax (Biecheler) Horiguchi ex Yuki et Fukuyo (Gonyaulacales, Dinophyceae) is a phototrophic marine dinoflagellate that produces an unusual paratabulate resting cyst that takes place after sexual reproduction.
Abstract: Alexandrium pseudogonyaulax (Biecheler) Horiguchi ex Yuki et Fukuyo (Gonyaulacales, Dinophyceae) is a phototrophic marine dinoflagellate that produces an unusual paratabulate resting cyst. Studies of vegetative and sexual reproduction were conducted on a clonal culture established from germination of a resting cyst from Fusaro Lagoon, Italy. Vegetative division in A. pseudogonyaulax takes place inside a vegetative cyst, from which two, or at times four, daughter cells originate. The daughter cells completely resynthesize new cell walls. Cyst formation takes place after sexual reproduction. A large biflagellate zygote is formed after a conjugation process in which one of the two gametes is engulfed by the other.
TL;DR: It is likely that carbonic anhydrase is needed to account for the expressed activity of these HCO3− using enzymes under natural conditions when CO2 is the inorganic C substrate supplied to the organism.
Abstract: The possible roles of intra-and extracellular carbonic anhydrase in cyanobacterial and algal photosynthesis are discussed. Carbonic anhydrase is likely to have a role in photosynthetic (C3 biochemistry) inorganic C acquisition by most algae under their natural growth conditions. The inorganic C substrate, intracellular location, metabolic roles and taxonomic distribution of non-photosynthetic carboxylases of algae and cyanobacteria are reviewed. From the quantitative role of these (cytosolic phosphoenolpyruvate carboxylase in red and green algae; acetyl CoA carboxylase predominantly in plastids in all taxa) it is likely that carbonic anhydrase is needed to account for the expressed activity of these HCO3− using enzymes under natural conditions when CO2 is the inorganic C substrate supplied to the organism.
TL;DR: Real ecological differences are demonstrated between the alternate isomorphic phases of this alga, with gametophytes apparently adopting a strategy of greater exploitation of favourable conditions to offset greater loss in unfavourable times, while tetrasporophytes maintain a somewhat more stable density throughout the year.
Abstract: Seasonal alternation of life-history phase dominance in a Vancouver population of Mazzaella splendens (Setchel et Gardner) Hommersand (Gigartinaceae, Rhodophyta) is the result of temporally synchro...
TL;DR: The iron concentration in coastal seawater collected from the Japan Sea, where rocks or rock beds are covered with coralline algae, is extremely low <2 nM Fe).
Abstract: The iron uptake rates of the brown macroalga Laminaria japonica Areschoug and the coralline alga Lithophyllum yessoense Foslie were determined using 59Fe as a tracer. The uptake rates of Laminaria were saturated at a higher level of iron than Lithophyllum. Furthermore, the saturated uptake rate of Laminaria was approximately 50 times higher than that of Lithophyllum. The growth of Laminaria, the brown macroalga Undaria pinnatifidaHarvey (Suringar) and Lithophyllum was compared in iron-rich and iron-limited media. A medium enriched with iron promotes the growth of Laminaria and Undaria. In contrast, Lithophyllum grew even in an iron-limited medium <1 nM Fe). The iron concentration in coastal seawater collected from the Japan Sea, where rocks or rock beds are covered with coralline algae, is extremely low <2 nM Fe). This may explain why coralline algae (Lithophyllum) dominate, whereas growth of brown macroalgae is severely limited.
TL;DR: Five taxa of green soil algae, in five genera, survived 35 years of desiccation in the laboratory, a decrease of two taxa since the previous study, down from 2000 viable cells per gram ten years ago.
Abstract: Five taxa of green soil algae, in five genera, survived 35 years of desiccation in the laboratory, a decrease of two taxa since our 25-year study. We determined that in each gram of dry soil approximately 30–50 algal cells were still viable after 35 years, down from 2000 viable cells per gram ten years ago.
TL;DR: Results demonstrated that the chlorophyll a content per cell of C. brevifilum changed with photon flux density, but prey density had no effect, and mixotrophic algae that are predominantly heterotrophic have also been shown to alter their chlorophylling content.
Abstract: The chlorophyll content of photosynthetic algae varies as a response to changes in photon flux density. Mixotrophic algae that are predominantly heterotrophic have also been shown to alter their chlorophyll a content as a response to changes in prey density. The marine flagellate Chrysochromulina brevifilum Parke et Manton (Prymnesiophyceae) was subjected to a range of photon flux densities, both with and without Marsupiomonas pelliculata Jones (Pedinophyceae) as a prey organism, and the ingestion of prey, chlorophyll a content, carbon and nitrogen content and cell size were monitored. Results demonstrated that the chlorophyll a content per cell of C. brevifilum changed with photon flux density, but prey density had no effect. Under a relatively low photon flux density (25 μmol photons m−2 s−1) both the ingestion of prey and the cellular concentration of chlorophyll a were greater than under a higher photon flux density (100 μmol photons m−2 s−1). However, the recent history of cultures of C. bre...
TL;DR: An assessment of anatomical features suggests that the occurrence of two pericentral cells in vegetative axes provides a stable basis for delimiting the subgenus Chondrophycus from the sub genus Laurencia, in which four pericentrals cells are found.
Abstract: The vegetative and reproductive anatomy of some species of Laurencia Lamouroux (Ceramiales, Rhodophyta) belonging to the subgenus Chondrophycus Tokida et Saito [L. tumida Saito et Womersley, L. intermedia Yamada, L. capituliformis Yamada and L. maris-rubri sp. nov.] have been investigated using type and additional material from Australia, Korea, Japan and the Red Sea. The species share several features: (1) vegetative axial segments with two pericentral cells, (2) procarp-bearing segments with four pericentral cells, the fourth of which becomes the supporting cell of the carpogonial branch, (3) tetrasporangia produced from the second pericentral cell of fertile axial segments and (4) the production of additional tetrasporangium-bearing pericentral cells. An assessment of these anatomical features suggests that the occurrence of two pericentral cells in vegetative axes provides a stable basis for delimiting the subgenus Chondrophycus from the subgenus Laurencia, in which four pericentral cells are...
TL;DR: A molecular phylogeny of the diatoms has been constructed from the nucleotide sequence of two domains of the nuclear-encoded large subunit ribosomal RNA in four centric and four pennate species, finding the Centrales and Pennales appear to be paraphyletic.
Abstract: A molecular phylogeny of the diatoms has been constructed from the nucleotide sequence of two domains of the nuclear-encoded large subunit ribosomal RNA in four centric and four pennate species Distance and parsimony analyses support the monophyly of the diatoms and their closeness to the chrysophytes The Centrales (radially symmetrical) appear to be paraphyletic: the centric Lithodesmium undulatum Ehrenberg (Lithodesmiales, Lithodesmiaceae) is associated with the pen-nate lineage In the Pennales (bilaterally symmetrical), the araphids also appear to be paraphyletic These phylogenetic inferences are in close congruence with those previously obtained from 18S rRNA data (Bhattacharya et al 1992; Medlin et al 1993) The evolutionary relationships of diatom families inferred from the ribosomal RNA data are discussed in relation to the fossil record
TL;DR: Sexual reproduction and protoplast structure are used to check the classification of the naviculoid genus Placoneis Mereschkowsky (Bacillariophyta) to find the sister group to the cymbelloid and gomphonemoid diatoms.
Abstract: Sexual reproduction and protoplast structure are used to check the classification of the naviculoid genus Placoneis Mereschkowsky (Bacillariophyta). The gametangia are closely associated within a robust mucilage capsule throughout auxosporulation, and pairing is ± random with respect to asymmetries of the frustule and protoplast. Two gametes are produced per gametangium, which are morphologically identical but differentiated into active and passive (physiological anisogamy). The supernumerary nuclei from meiosis II begin to degenerate soon after telophase II, but can still be detected in the initial cells. The gametes become rearranged within the gametangia after meiosis II and plasmogamy takes place via a single, simple aperture. The auxospores expand parallel to the apical axes of the gametangia. The classification of Placoneis in the Cymbellales, as the sister group to the cymbelloid and gomphonemoid diatoms, is supported by valve and protoplast structure, the method ofchloroplast division, an...
TL;DR: A new species of the genus Scrippsiella was described in this paper, which is a peridinioid, autotrophic, marine dinoflagellate characterized by a strong dorso-ventral compression and the presence of a small horn on the hypotheca.
Abstract: A new species of the genus Scrippsiella, Scrippsiella ramonii sp. nov. is described on the basis of observations with light and electron microscopes. The culture was obtained from germination of a resting cyst collected in surface sediments of the Gulf of Naples (Italy). S. ramonii is a peridinioid, autotrophic, marine dinoflagellate characterized by a strong dorso-ventral compression and by the presence of a small horn on the hypotheca. The resting cyst is ovoid and ornamented with numerous long calcareous spines. The plate pattern of vegetative cells and the morphological characters of the resting cyst are remarkably similar to those of S. precaria Montresor et Zingone, described from the same geographic area.
TL;DR: Fluence rate-response curves (P vs I curves) were measured in several species of stream macroalgae from laboratory culture and from a small soft-water stream to study light saturated and light saturated photosynthesis of laboratory-grown algae.
Abstract: Fluence rate-response curves (P vs I curves) were measured in several species of stream macroalgae from laboratory culture and from a small soft-water stream. Photosynthesis of laboratory-grown algae was light saturated at 24 μmol photons m−2 s−1 of white light in Klebsormidium rivulare (Kutzing) Morison et Sheath, at 25.51 μmol m−2 s−1 in Batrachospermum helminthosum Bory emend. Sheath et al., at 35 μmol m−2 s−1 in Balbiania investiens (Lenormand) Sirodot (cultivated at 4 μmol m−2 s−1), at 42 μmol m−2 s−1 in Microspora quadrata Hazen, at 60 μmol m−2 s −1 in Vaucheria bursata (O.F. Muller) C. Agardh (= V. sessilis De Candolle), Stigeoclonium tenue (C. Agardh) Kutzing, Audouinella hermannii (Roth) Duby in De Candolle, Balbiania investiens (cultivated at 40 μmol m −2 s−1) and at 67 μmol m−2 s−1 in Cladophora glomerata (Linnaeus) Kutzing. Photosynthesis of algae taken from the Bieber stream was light saturated at significantly higher photon irradiances of 115 μmol m−2 s−1 in Batrachospermum helminth...
TL;DR: A detailed morphological and anatomical account of Austrolithon intumescens is provided and new data is presented for Boreolithon van-heurckii.
Abstract: The Austrolithoideae (subfam. nov.), comprising Austrolithon (gen. nov.) and Boreolithon (gen. nov.), differs from other subfamilies in the Corallinaceae (Corallinales, Rhodophyta) in possessing multiporate tetrasporangial conceptacles and in lacking cell fusions, secondary pit connections and genicula. Austrolithon and Boreolithon both include single known species: A. intumescens (sp. nov.) from southern Australia and B. van-heurckii (comb. nov.) from the British Isles and France. Austrolithon and Boreolithon differ in growth form (unconsolidated vs. encrusting), habit (almost entirely endophytic vs. epigenous) and thallus construction (partly diffuse and partly pseudoparenchymatous and monomerous vs. largely pseudoparenchymatous and dimerous). Type material of both species was examined. A detailed morphological and anatomical account of Austrolithon intumescens is provided and new data are presented for Boreolithon van-heurckii. Information on etymology, collections examined, and distribution, ...
TL;DR: Chrysochromulina spinifera (Fournier) Pienaar et Norris displays a novel feeding mechanism where a water current generated by flagellar movement brings food particles to the cell.
Abstract: Chrysochromulina spinifera (Fournier) Pienaar et Norris displays a novel feeding mechanism. A water current generated by flagellar movement brings food particles to the cell. These particles adhere...
TL;DR: H. groeneri appears to have a somewhat wider distribution in southern Africa than H. woelkerlingii, and is ascribed to the genus Heydrichia on the basis of a type of sporangial development in which the successive production of tetrasporangia results in multiple sporangia stalk cells.
Abstract: Heydrichia groeneri sp. nov., the second recorded species of the genus, is described from western Cape Province, South Africa, and southern Namibia. It is ascribed to the genus Heydrichia on the ba...
TL;DR: Investigations indicate that the SSU gene provides suitable divergence for assessing relationships among the fucalean families, and ally the Notheiaceae with the Fucales, although not closely with its virtually obligate host, Hormosira banksii of the monotypic HormOSiraceae.
Abstract: Partial nucleotide sequences of the nuclear small-subunit ribosomal RNA genes (SSU), as inferred from polymerase chain reaction (PCR)-amplified products, have been determined for Caulocystis cephalornithos (Labillardiere) Areschoug (Cystoseiraceae), Hormosira banksii (Turner) Decaisne (Hormosiraceae), Sargassum vestitum (R. Brown ex Turner) C. Agardh (Sargassaceae) and Notheia anomala Harvey et Bailey (Notheiaceae). These taxa are referred to three of the six families currently placed in the order Fucales, plus the monotypic Notheiaceae, which has variously been placed in the Chordariales, the Fucales or the Notheiales. Our investigations indicate that the SSU gene provides suitable divergence for assessing relationships among the fucalean families. Phylogenetic analyses of the partial SSU gene sequences ally the Notheiaceae with the Fucales, although not closely with its virtually obligate host, Hormosira banksii of the monotypic Hormosiraceae. The data are equivocal as to the positioning of the...
TL;DR: Measurements of parameters related to photosynthesis, with particular reference to the mechanism of inorganic C acquisition, were made on the obligate epiphyte Notheia anomala and on its most usual basiphytes, Hormosira banksii (Turner) Decaisne.
Abstract: Measurements of parameters related to photosynthesis, with particular reference to the mechanism of inorganic C acquisition, were made on the obligate epiphyte Notheia anomala Harvey et Bailey (Phaeophyta: Fucales) and on its most usual basiphyte, Hormosira banksii (Turner) Decaisne (Phaeophyta: Fucales). The work on Hormosira banksii included a comparison of specimens which are normally emersed at low tide on rock platforms with specimens which are normally submersed in rockpools at low tide; the rockpool specimens are those which most commonly bear Notheia anomala. No significant differences were detected for any of the characteristics tested, i.e. photosynthetic rate as a function of incident photon flux density, external inorganic C concentration and plant N content; capacity to use HCO3−; diel changes in titratable acidity of cell contents (‘CAM-like’ behaviour); rates of dark 14C-inorganic C fixation; δ13C values of plant organic C. These data are consistent with there being no significant ...
TL;DR: It is concluded that the flagellar canal and accessory pore canal are not attached to each other and that the 'Prorocentrum' type of flageLLar apparatus and cell architecture is most likely the result of episome/hyposome compression.
Abstract: We have determined the three-dimensional structure of the flagellar apparatus in Prorocentrum micans Ehrenberg (Dinophyceae). The flagellar apparatus consists of two basal bodies that lie at approximately a 35 degrees angle to one another. Each basal body bears a typical dinophycean complement of microtubular and fibrous components. Unlike the majority of Dinophyceae, the longitudinal microtubular root lies adjacent to the longitudinal basal body and abuts the transverse basal body. The transverse microtubular root is associated with an extension of microtubules that is directed posteriorly (dorsal, using proposed terminology) into the cell to a region adjacent to the nucleus. On the opposite side of the flagellar apparatus, the microtubules of the peduncle extend posteriorly (dorsal, using proposed terminology) from the flagellar canal region. The microtubules extend for several micrometers and the peduncle is closely associated with a complex striated collar that circumscribes the flagellar canal and its components. We report on the three-dimensional nature of the flagellar canal and accessory pore canal region. We conclude that the flagellar canal and accessory pore canal are not attached to each other and that the 'Prorocentrum' type of flagellar apparatus and cell architecture is most likely the result of episome/hyposome compression.
TL;DR: Characteristics of mitosis and vegetative features, both those newly observed and those confirmed (especially the presence of connections between chloroplast lobes), support the removal of G. vacuolala from the Glaucophyta and its placement in the Rhodophyta.
Abstract: The ultrastructure of vegetative cells and cell division has been examined in Glaucosphaera vacuolala Korshikov. Features either not found or not denoted before include apparent intercisternal fusions within each Golgi body and fibrillar tracts possibly utilized by Golgi vesicles. Mitosis is closed except for large polar gaps and a spherical, presumptive MTOC (microtubule organizing centre) is present at prophase. The MTOC flattens by metaphase to fill the polar gap, becoming the focus of spindle microtubules. No NAO (nucleus associated organelle) was observed. All aspects of mitosis except the absence of an NAO are consistent with mitosis in red algae; most are not consistent with members of the Glaucophyta. Characteristics of mitosis and vegetative features, both those newly observed and those confirmed (especially the presence of connections between chloroplast lobes), support the removal of G. vacuolala from the Glaucophyta and its placement in the Rhodophyta. Also noted in this investigation...