• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.257-260
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• 2001

The effects of light, desiccation and salinity on the discharge of spores in Korean agarophyte, Gracilaria verrucosa were studied. Among the examined factors, light after darkness was the most effective for spore discharge. The maximum release of tetraspores was induced at 24 h after the treatment. Desiccation also seems to be conductive to the release of tetraspores. However, its effect, as in treatment of distilled water for salinity, was hardly found in induction of carpospore discharge. This may suggest that spore discharge in this alga is primarily related with photoperiodic rhythm. Also it appears that the amount of light energy received by fertile thalli also significantly affects to the spore release, considering relationship between the amount of the discharged spores and the elapsed time after treatment.

• ALGAE
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• v.18 no.2
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• pp.177-181
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• 2003

Variation in seasonal growth, phenology and periodicity in spore shedding in Polysiphonia platycarpa $B{\oslash}rgesen$ occurring on the coast of Visakhapatnam, India, have been described to know the growth behaviour, reproductive periodicity and spore producing capacities. This alga occurs for a short period from December to May in the intertidal region of the Visakhapatnam coast, showing maximum growth during January/February. Tetrasporophytic, carposporophytic and antheridial plants were observed in all months of their occurrence in the field. But the vegetative plants were not seen in January and February and all the plants collected were reproductive. The tetraspore and carpospore shedding was observed during all the six months of their occurrence.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.387-393
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• 2014

We propose Cryptonemia asiatica sp. nov. from Korea and Japan. We used molecular analyses of plastid-encoded rbcL and morphological observations to resolve the taxonomic identities of C. lactuca from Korea, C. luxurians from Japan, and C. seminervis from Spain. Specimens of C. lactuca and C. luxurians fell within the same molecular phylogenetic clade (with 100% bootstrap support) and were clearly separated from specimens of C. luxurians collected from the type locality in Brazil. Our analyses demonstrated identical molecular sequences between C. seminervis specimens from Spain and C. lomation specimens from France. Morphological characteristics of the new species, C. asiatica include prominent midribs through the mid thallus, a cortex 4-6 cells thick, and a blade with undulate margins. Molecular evidence indicates that specimens from Korea and Japan previously assigned to C. lactuca and C. luxurians, respectively, should be reassigned to Cryptonemia asiatica. Binomial C. luxurians from Brazil should be resurrected as the independent species of Cryptonemia.

• ALGAE
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• v.19 no.4
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• pp.283-292
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• 2004

Psilothallia is a ceramiaceous red algal. genus that includes three species worldwide: P. dentate, P. siliculosa, and P. striate. The latter two species are limited to Australian waters, and P. dentate occurs in Japan. We here report the detailed morphology of P. dentate, and also determined plastid protein-coding psbA in P. dentate and putative relatives. Psilothallia dentate is distinguished by compressed thalli with alternate-distichous determinate branchlets, six periaxial cells, rhizoidal filaments in axes, cystocarps with 7-8 involucral filaments, spermatangia on branched filaments, and tetrahedrally divided tetrasporangia on branched filaments. Psilothallia dentate is also unusual in that cystocarps, spermatangial clusters, and tetrasporangial tufts are formed on short adventitious indeterminate branches arising on axils of determinate branchlets. The phylogenetic trees of psbA sequences show that P. dentata was nested in a monophyletic Glade comprising Ptilota, Neoptilota, and Plumaria. This result suggests that the taxonomic position of P. dentate may be transferred from the tribe Rhodocallideae to the Ptiloteae.

• ALGAE
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• v.20 no.4
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• pp.325-331
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• 2005

Populations of Campylaephora borealis (Nakamura) Seo, Cho et Boo and C. crassa (Okamura) Nakamura show a year-around occurrence of all life-history stages. Such a concurrency of life-history stages produces problems in recognizing species in the field. Here, we invesitgated the morphological variation and life-history stages of both species using a statistical character analysis. Life-history stage was correlated with the seawater temperature in C. borealis, whereas it was dependant on biomass in C. crassa. Thalli had dichotomous branches with adaxial branchlets. The statistics showed that the seasonal change in morphology of C. borealis was significantly different from that of C. crassa in seven qualitative characters and five quantitative characters (p < 0.001), although six quantitative features including tetrasporangial size were similar in both species. The morphological difference between the two species may be due to the annual variation of branchlet number and the variance of branch subangle.

• ALGAE
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• v.28 no.3
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• pp.241-266
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• 2013

The mangrove algal flora of Guam and the Federated States of Micronesia has been poorly explored. We add to our knowledge of this region by observations of collections from these regions. This paper presents new and additional records of: Rhodophyta-Acrochaetium globosum, Colaconema sp., Caulacanthus indicus, Bostrychia moritziana / B. radicans, B. radicosa, B. simpliciuscula, B. kelanensis and B. tenella, Murrayella periclados, and Caloglossa ogasawaraensis; Chlorophyta-Boodleopsis carolinensis; and Phaeophyceae-Dictyota adnata, Dictyotopsis propagulifera, and Canistrocarpus cervicornis. Most specimens were cultured to investigate their reproductive biology and many specimens were further identified using molecular data. Low molecular weight carbohydrates (dulcitol, sorbitol, and digeneaside) were identified in samples of B. radicosa and B. simpliciuscula. We also present data on manganese-rich deposits found on B. simpliciuscula and B. tenella in culture, possibly formed by epiphytic bacteria.

• ALGAE
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• v.28 no.3
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• pp.233-240
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• 2013

Despite specimens' large size and ease of collection in northeast Asian waters, the species diversity of the genus Grateloupia still needs more research in Korea. We investigated plastid rbcL sequences and carried out detailed morphological observation on flattened halymeniacean red alga collected in twelve locations around Korea and Japan. We describe Grateloupia jejuensis sp. nov. based on the distinct clade with high support in our rbcL tree. Grateloupia jejuensis is characterized by solitary or caespitose habit and flattened thalli with discoid holdfast, cartilaginous texture, and blunt or bifid axis. Grateloupia jejuensis was distantly related to G. elata and G. cornea, which have been morphologically confused with the former, and it formed a sister relationship with Prionitis filiformis from California, USA in the rbcL tree.

• Fisheries and Aquatic Sciences
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• v.14 no.2
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• pp.118-122
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• 2011

Polysiphonia senticulosa Harvey (Ceramiales: Rhodophyta) was recorded for the first time in Korea, and its vegetative and tetrasporangial morphologies are described. This species is characterized by the combined features of having a vegetative axial segment with 4 pericentral cells, a main axis without cortication, pseudodichotomous branching, branches with sharply pointed apical cells, flexuous branches hooked backward below, the presence of cicatrigenous branches, axillary endogenous stichidia, and the production of 1-3 tetrasporangia per stichidium. Based on this study, it is distinguished from Polysiphonia morrowii Harvey by its flexuous branches and the number of tetrasporangia produced per stichidium.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.198-202
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• 2015

In the course of the survey of indigenous species, a red algal Hypnea species was collected from eastern coast of Korea. This species is distinct from other species of Hypnea in having percurrent and cylindrical axis, linear to lanceolate branchlets in axes except their lower portion and medullary cell walls without lenticular thickenings. This Korean entity is identified as Hypnea chordacea K$\ddot{u}$tzing (Gigartinales, Rhodophyta) based on those features. This is the first record of Hypnea chordacea in Korea.

• ALGAE
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• v.20 no.1
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• pp.15-23
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• 2005

Polysiphonia pacifica is rhodomelaceous red algal species that includes five varieties in Pacific Ocean: P. pacifica var. delicatula, P. pacifica var. distans, P. pacifica var. determinata, P. pacifica var. disticha, and P. pacifica var. gracilis. We here report morphology and phylogeny of P. pacifica to confirm the relationships among previously described varieties as a loan of type specimens from US and to assess phylogenetic relationships of closely related species using plastid protein-coding rbcL gene. Polysiphonia pacifica is distinguished by having creeping filaments attached by unicellular rhizoids not cut off by cross walls, four pericentral cells, ecorticate, trichoblasts rare, ultimate branchlets attenuate at the tip but not pungent, and tetrasporangia in long straight series in the ultimate branchlets. The protein-coding plastid rbcL gene sequence data show that P. pacifica is distinctly different from the superficially similar species, P. morrowii and P. stricta. However, the rbcL sequences of P. pacifica var. pacifica and var. disticha are identical though they have morphological variation.