Ultrastructure of the marine benthic dinoflagellate Plagiodinium belizeanum (Dinophyceae) from the southeast Pacific island of Okinawa, Japan

作者：Wakeman Kevin C^*; Hoppenrath Mona; Yamaguchi Aika; Gavelis Greg S; Leander Brian S; Nozaki Hisayoshi

来源：Phycologia, 2018, 57(2): 209-222.

DOI：10.2216/17-43.1

• Classification
• Epifluorescence
• Madanidinium
• Pileidinium
• Planodinium
• Pseudadenoides
• Sabulodinium
• Scanning electron microscopy
• Taxonomy
• Thecadinium kofoidii
• Transmission electron microscopy
• Ultrastructure

We isolated Plagiodinium belizeanum into clonal culture from the Pacific island of Okinawa (Japan) and characterized it using a combination of light microscopy, scanning electron microscopy, transmission electron microscopy and 18S/28S ribosomal (r) gene sequences. Although molecular phylogenetic analyses of 18S rDNA and 28S rDNA sequences were unable to resolve the phylogenetic position of P. belizeanum within dinoflagellates, the ultrastructural data provided some new traits for the species. For instance, double-membrane-bound vesicles, distinct from the mitochondria, were interpreted as autolysosomes containing electron-dense virus particles. The thecal plate pattern was Po 1' 0a 5'' 5(6)C 4S 5''' 0p 1'''', which is slightly different from the original description in having an additional epithecal plate and four sulcal plates. The laterally flattened cells were 22-34 mu m long, 11-13 mu m deep, and 15-18 mu m wide and contained a peridinin-type plastid with lobes radiating from a central pyrenoid that lacked starch sheaths and was traversed by stacks of thylakoids. This isolate represents the first record of the species in Japan, and the new ultrastructural and DNA sequence data were used to emend the species description.

• 出版日期2018-3