Takeaki Hanyuda

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The molecular phylogeny of brown algae was examined using concatenated DNA sequences of seven chloroplast and mitochondrial genes (atpB, psaA, psaB, psbA, psbC, rbcL, and cox1). The study was carried out mostly from unialgal cultures; we included Phaeostrophion irregulare and Platysiphon glacialis because their ordinal taxonomic positions were unclear.(More)
The phylogeny of ligulate and sulfuric-acid containing species of Desmarestia, occurring worldwide from polar to temperate regions, was revised using a multigenic and polyphasic approach. Sequence data, gametophyte characteristics, and sporophyte morphology support reducing a total of 16 taxa to four different species. (1) D. herbacea, containing(More)
Podostemaceae are aquatic herbs and are famous for their anomalous vegetative morphology, occurring only in rapids. Because of its peculiar morphology, there were no established theory nor accepted opinion on the phylogenetic position. Especially, Cusset and Cusset (1988) proposed the new class, Podostemopsida beside the Magnollopsida and Liliopsida. We,(More)
The occurrence and diversity of barnacles attached to the hulls of two intercontinental bulk carriers were studied at the port in Osaka Bay, Japan, to assess the potential risk of introduction of exotic species to the inner part of the bay. Barnacles were sampled from the bulbous bows, near the midship draft marks, and around the propeller posts and(More)
gene have been reported to date. Four new cases from Caulerpales, Ulvophyceae are described here. In the genus Caulerpa, the presence of an intron was unstable even in the infraspecific taxa. Based on comprehensive comparisons of the inserted positions, lengths of introns and so on, the presence of at least three kinds of introns, which probably have(More)
A previously unknown species of kelp was collected on Kagamil Island, Aleutian Islands. The species can be easily distinguished from any known laminarialean alga: the erect sporophytic thallus is composed of a thin lanceolate blade attaining ∼2 m in height and ∼0.50 m in width, without midrib, and the edge of the blade at the transition zone is thickened to(More)
Laminarialean species (so-called kelps) are the largest photosynthetic organisms in aquatic environments, constituting significant ecological components of coastal ecosystems. The largest kelps such as Macrocystis exhibit differentiation between stipe and blade, as well as buoyancy to maintain the distal portion at the water's surface for photosynthesis,(More)
Platysiphon verticillatus, a brown alga endemic to the Arctic, was described based on vegetative specimens collected at Inglefield Bay, West Greenland. The species is distinctive in having a lanceolate blade-like thallus terminated by a terete portion, both covered with hair-like assimilatory filaments. Punctaria glacialis was described from Eastern(More)
Wittrockiella is a small genus of filamentous green algae that occurs in habitats with reduced or fluctuating salinities. Many aspects of the basic biology of these algae are still unknown and the phylogenetic relationships within the genus have not been fully explored. We provide a phylogeny based on three ribosomal markers (ITS, LSU, and SSU rDNA) of the(More)