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Journal Articles - UP - MSI

Permanent URI for this collectionhttps://repository.unesco.gov.ph/handle/123456789/50

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    A unique reproductive strategy in the mushroom coral Fungia fungites
    Eyal-Shaham, Lee; Eyal, Gal; Ben-Zvi, Or; Sakai, Kazuhiko; Harii, Saki; Sinniger, Frederic; Hirose, Mamiko; Cabaitan, Patrick; Bronstein, Omri; Feldman, Bar; Shlesinger, Tom; Levy, Oren; Loya, Yossi (Springer Science and Business Media LLC, 2020-09-30)
    The vast majority of scleractinian corals are either simultaneous hermaphrodites or gonochoric. Exceptions to these are rare. Nevertheless, species belonging to the family Fungiidae are known to exhibit a wide variety of reproductive strategies. We examined the reproductive ecology of the mushroom coral Fungia fungites in Okinawa. Our study was conducted as part of a long-term, wide-ranging project (2009–2010 and 2013–2017) which explored the unique reproductive strategies of several species belonging to the family Fungiidae. Here we report the co-occurrence of males, females, and hermaphrodite individuals in a long-term monitored population of the reproductively atypical brooder coral F. fungites within the family Fungiidae. F. fungites status as a single-polyped solitary coral, was used to perform manipulative experiments to determine the degree of dependence of an individual coral on its conspecific neighbors for reproduction, and examined whether a constant sperm supply is obligatory for the continuous production of planulae. Isolated females of F. fungites exhibited a distinctive reproductive strategy, expressed in continuously releasing planulae also in the absence of males. Observations conducted on a daily basis for 2.5 months (throughout the reproductive season of 2015) revealed that some of these individuals released planulae continuously, often between tens and hundreds every day. In an effort to explain this phenomenon, three hypotheses are discussed: (1) Self-fertilization; (2) Asexual production of planulae (i.e., parthenogenetic larvae); and (3) Extended storage of sperm. Finally, we emphasize the importance of continuous and long-term monitoring of studies of coral reproduction; through further genetic studies of coral populations representing a broad range of species and their larval origin.
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    The harmful unarmored Dinoflagellate Karlodinium in Japan and Philippines, with reference to ultrastructure and micropredation of Karlodinium azanzae sp. nov. (Kareniaceae, Dinophyceae)1
    Benico, Garry; Takahashi, Kazuya; Lum, Wai Mun; Yñiguez, Aletta T.; Iwataki, Mitsunori (Phycological Society of America, 2020)
    Twenty-six cultures of the harmful marine dinoflagellate Karlodinium, isolated from Japanese and Philippine coastal waters, were examined using LM, SEM, and molecular phylogeny inferred from ITS and LSU rDNA. Seven Karlodinium species (six from Japan and four from Philippines), K. australe, K. ballantinum, K. decipiens, K. gentienii, K. veneficum, K. zhouanum, and a novel species Karlodinium azanzae sp. nov., were identified based on their morphology and phylogenetic positions.Karlodinium azanzae from Manila Bay, Philippines was further characterized by TEM, HPLC (chloroplast pigment), and bioassay on brine shrimp and other marine zooplankton. Cells of K. azanzae were the largest (mean 25.3 µm long) in Karlodinium, possessed numerous tiny reflective particles, starch grains, and lipid granules, and usually swam at the bottom of the culture vessel. The straight apical structure complex and a ventral pore were common to the genus. The longitudinally elongated nucleus was located at the center, and the yellowish chloroplasts contained an embedded pyrenoid and carotenoid pigments typical of the genus (i.e., fucoxanthin as major carotenoid with its derivatives). TEM revealed a part of the flagellar apparatus, of which the long striated ventral connective is the first report in the Kareniaceae. Phylogenetic trees showed closest affinity of K. azanzae with K. australe and K. armiger. The new species could be differentiated from related species by cell size, position of the nucleus, and characteristic swimming behavior. Lethality of K. azanzae to large zooplankton and micropredation using a developed peduncle was also observed.
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    Manzaea minuta gen. & comb. nov. (Scytosiphonaceae, Phaeophyceae) from the tropical Northwestern Pacific Ocean
    Santiañez, Wilfred John E.; Kogame, Kazuhiro (Philippine Journal of Systematic Biology, 2022-07-11)
    Recent molecular-assisted taxonomic studies on the brown algal genus Hydroclathrus has resulted in discoveries of new taxa in the family Scytosiphonaceae, both at the genus and species level. However, phylogenetic studies on Hydroclathrus based on wide geographical sampling also suggested that the genus is not monophyletic. That is, one of the recently described species Hydroclathrus minutus is consistently segregated from the Hydroclathrus main clade. We propose here to segregate H. minutus from the brown algal genus Hydroclathrus and establish the new monotypic genus Manzaea (i.e., Manzaea minuta gen. & comb. nov.) based on information on molecular phylogenetics and morpho-anatomy. Morphologically, M. minuta is similar to Hydroclathrus and Tronoella in having clathrate (net-like) and spreading thalli but is differentiated from the latter two genera in having membranous thalli that are sometimes interadhesive resulting in portions of the thallus forming amorphous clumps. Additionally, Manzaea is distinguished from both clathrate genera in having thick-walled medullary cells and short closely arranged quadriseriate plurangia. Phylogenetic analyses (Maximum Likelihood and Bayesian Inference) based on single (plastidial psaA and rbcL genes) and concatenated (cox3 + psaA + rbcL) genes showed that M. minuta is consistently segregated from the highly supported clade of Hydroclathrus species and often clustering with Tronoella and/or Rosenvingea. Our proposal further increases the diversity of monotypic genera in the Scytosiphonaceae and underscores the need to conduct further studies on tropical seaweed biodiversity.
    WJES thanks Dr. Gavino C. Trono, Jr. and Dr. Edna T. Ganzon-Fortes for the inspiration and encouragement to conduct seaweed biodiversity and systematics research. WJES is funded by the University of the Philippines through the Balik PhD Program of the Office of the Vice President for Academic Affairs (OVPAA-BPhD-2018-05), the University of the Philippines Diliman through the In-house research grant of the Marine Science Institute, and the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Government of Japan under the Monbukagakusho Scholarship Grant. WJES also acknowledges the support of the Department of Science and Technology (DOST)-Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (PCAARRD) of the Government of the Philippines through the DOST Balik Scientist Program.