• Title/Summary/Keyword: Dictyotales

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Morphological Study of the Marine Algal Genus Padina (Dictyotales, Phaeophyceae) from Southern Philippines: 3 Species New to Philippines

  • Geraldino, Paul John L.;Liao, Lawrence M.;Boo, Sung-Min
    • ALGAE
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    • v.20 no.2
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    • pp.99-112
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    • 2005
  • This monographic study presents morphological descriptions of eight species of Padina collected from the Visayas and Mindanao regions of southern Philippines, including distributions of each species and a taxonomic key for all the species examined. Of these species, three are new records for the Philippines, namely: P. fernandeziana Skottsberg and Levring, P. jonesii Tsuda and P. moffittiana Abbott and Huisman. One species, P. antillarum (Kützing) Piccone, represents a new nomenclatural record, which is applied to a Philippine species for the first time. Four species previously reported in the Philippines are reconfirmed and described P. australis Hauck, P. minor Yamada, P. boryana Thivy and P. sanctae-crucis Borgesen. All eight species studied have distromatic thalli, except for P. antillarum which is tetrastromatic. Three of these have indusiate sporangia, namely: P. sanctae-crucis, P. moffittianaand P. fernandeziana.

Taxonomic Reassessment of the Genus Padina (Dictyotales, Phaeophyta) from the Gulf of California

  • Riosmena-Rodriguez, Rafael;Paul-Chavez, Litzia;Hernandez-Carmona, Gustavo;Lopez-Vivas, Juan Manuel;Casas-Valdez, Margarita
    • ALGAE
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    • v.24 no.4
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    • pp.213-229
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    • 2009
  • A monographic reassessment of Padina Adanson species from the Gulf of California was developed based on an exhaustive review of the character and characters states that have been used to delimit species in recent and historically valuable collections. Eight names (P. caulescens Thivy in Taylor, P. concrescens Thivy in Taylor, P. crispata Thivy in Taylor, P. durvillaei Bory Saint-Vincent, P. gymnospora [Kutzing] Sonder, P. mexicana Dawson, P. tetrastromatica Hauck and P. vickersiae Hoyt in Howe) were reported from the region. An analysis of 1,200 specimens led to the conclusion that only three species (P. durvillaei, P. concrescens and P. mexicana) can be recognized for the area based on four discriminating characters: presence of calcium carbonate in the cell wall; number of medullary cell layers in the basal area; number of medullary cell layers in the middle part and presence/absence of cortical cells. Comparative analysis of the species in the Gulf of California in relation to other recently evaluated species has shown a clear distinction among them suggesting Padina species were overestimated in our area.

Population Structure and Reproduction of Padina concrescens Thivy(Dictyotales: Phaeophyta) in Southwest Baja California Peninsula, Mexico

  • Rafael, Riosmena-Rodriguez;Consuelo, Ortuno-Aginrre
    • ALGAE
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    • v.24 no.1
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    • pp.31-38
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    • 2009
  • The brown algae padina concrescens is widely distributed in the northwestern Pacific Mexico. We described the population of P. concrescens based on population parameters such as cover, density and size structure and reproduc-tion at two levels tide at the intertidal area in the southwestern Baja. California Peninsula. Monthly visits from January to December 2003 were done. Both cover and density were measured in situ by quadrants method. Samples were collected to obtain size structure and percentage of reproductive fronds. Our results show there is sparial vari-ation in the population structure more than temporal. Thus, cover and density peak were at different months ineach tide level studied, the lower tide level shows the high values in cover as well as density. The frond develop-ment was observed in height/width ratio this relation was consistent only in the low tidal zone. Size class distribu-tion has consistently small size plants in both tide levels.Reproduction was seasonal in the tide channel but in both tide levels all the reproductive plants were tetrasporophyte. Our results suggest that this population is pseudopere-nial and it strongly as a consequence of the intense competition in the intertidal zone.

Morphological Characteristics of Brown Alga Spatoglossum crassum Tanaka (Dictyotaceae, Dictyotales), New to Korea

  • Hwang, Il-Ki;Kim, Hyung-Seop;Lee, Wook-Jae
    • ALGAE
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    • v.19 no.3
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    • pp.191-199
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    • 2004
  • Morphological and phonological characteristics of brown alga Spatoglossum crassum Tanaka new to Korea were described based on the field and the indoor cultured plants. The taxonomic characteristics of the plants were agreed to those from the type locality-submerged reproductive organs in cortex, anatomical features, and absence of phaeophycean hairs on the surface. But they have rudimentary midrib on lower portion of thallus. We can observe the young plants on November, adult ones in June, and senile ones in August. This species has an annual life-cycle in the field, starting with germ lings in early November. The differentiation of thallus is quite different from other species of genera in tribe Zonarieae, e.g. Zonaria and Homoeostrichus. Three different tissues, meristoderm, cortex and medulla are discerned. The outmost cortical one celled layer as a meristoderm produce cortex by unequal periclinal division. In the apical cell division, the primary inner cells are developed into 3-4 cell layered medulla of thallus. The distribution of this species extends from Korea to Shizuoka Peninsula (34°40'N) Japan, which is the type locality of this species.

Vegetative Anatomy and Tetrasporogenesis in Stoechospermum marginatum (C. Agardh) Kűtzing (Dictyotales, Phaeophyceae)

  • Bhamrah, Gunwant;Kaur, Inderdeep
    • ALGAE
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    • v.20 no.4
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    • pp.315-324
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    • 2005
  • Anatomical organization of Stoechospermum marginatum reveals small cortical cells with moderately dense cytoplasm, overlying a multilayered medulla comparatively poor in cytoplasmic contents. The anticlinal walls of cortical cells show local thickenings rich in alginic acids. Sori form on both thallus surfaces and show tetrasporangia, paraphyses and sterile-cells. The unicellular paraphyses are rich in sulphated polysaccharides whereas multicellular ones have abundance of not only polysaccharides, but also of vacuoles and phenols. The sterile-cells are modified cortical cells present on either side of the tetrasporangium and bear cytoplasmic strands towards soral cavity. Various stages of tetrasporogenesis are seen in a single sorus. The developing tetrasporangium shows a two layered wall, where the outer one is rich in alginic acid and inner has sulphated polysaccharides. An apical pad aids tetraspore release. Also involved in the release process are sterile-cells, paraphyses and polysaccharides.

Evidence for Taxonomic Status of Pachydictyon coriaceum (Holmes) Okamura (Dictyotales, Phaeophyceae) Based on Morphology and Plastid Protein Coding rbcL, psaA, and psbA Gene Sequences

  • Hwang, Il-Ki;Kim, Hyung-Seop;Lee, Wook-Jae
    • ALGAE
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    • v.19 no.3
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    • pp.175-190
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    • 2004
  • The morphological and molecular characteristics of Pachydictyon coriaceum (Holmes) Okamura (1899) are described. Plants are collected from Korea all year round and have maximum height from August to September. The monthly variability of thallus growth is in the way with that of the seawater temperature. Two types of thallus structures, thick cortical layer tallus type and thin cortical cell layer type, are distinguished according to growing seasons. The habit of Korean plants is also classified into two thallus types, slender type and wide type, based on the length and the width of internodes, but this distinction between two types is not supported by either anatomical or molecular characteristics. P. coriaceum shares typical morphology in branching pattern and morphogenetic processes with the other species of Dictyota: 1) multi-cellular cortical and medullar layer in the partial of thallus, 2) same development of thallus from apical meristem cell, and 3) sub-lineage within Dictyota species lineage in rbcL, psaA and psbA gene sequences analyses. These characteristics lead to propose the new combination of Dictyota coriacea (Homes) I.K. Hwang, H.S. Kim et W.J. Lee, comb. nov.

Marine Algal Flora on Goheung Coast, Korea

  • Sun, Bin;Seo, Tae-Ho;Cho, Jae-Kwon;Kim, Dae-Kwon;Yun, Soon-Ki;Shin, Hyun-Soo;Lee, Han-Sol;Shin, Jong-Ahm
    • Korean Journal of Environmental Biology
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    • v.29 no.1
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    • pp.31-45
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    • 2011
  • To understand the marine algal flora on Goheung coast, Korea, marine algae at 8 points were collected from November 2008 to February 2009 and from April to June 2009. Thirty-seven species (2 species of angiosperms, 5 chlorophytes, 12 phaeophytes, and 18 rhodophytes) occurred from fall to winter and 52 species (2 species of angiosperms, 9 chlorophytes, 18 phaeophytes, and 23 rhodophytes) occurred from spring to summer. Commonly occurring species were Ulva pertusa, Sargassum thunbergii, Hizikia fuziformis, and Gelidium amansii, and dominant species at most points were Ulva pertusa, Sargassum thunbergii, and Gelidium amansii. The average of the ratio of total rhodophytes and chlorophytes to phaeophytes ((R+C)/P) was 1.61 in fall to winter and 1.69 in spring to summer, and the average Laminariales/Fucales/Dictyotales (LFD) ratio was 1.14 in fall to winter and 1.18 in spring to summer. These results show that the marine algal flora of Goheung could be considered as temperate. The LFD ratio was fit for showing a feature of algal flora of Goheung. Species diversity index was high at Points 4~6 while low at Points 1 and 8. Detrended correspondence analysis (DCA) showed that the similarity of occurring species at Points 3 and 4 was higher than the other points from fall to winter, whereas the occurred species at Points 1~4 were similar from spring to summer. The average values of ecological evaluation index (EEI) of the investigation points were 6.8 from fall to winter and 6.3 from spring to summer, which means that the ecological environment of the investigation points were middle class and the EEI values of outer sea points were higher than the inner bay points.