Morphology, ultrastructure and taxonomy of the raphidophycean algaHeterosigma akashiwo

  • Yoshiaki Hara
  • Mitsuo Chihara


Heterosigma akashiwo and its related algae were re-examined by light and electron microscopes using cultured materials including type cultures of bothH. akashiwo andH. inlandica as well as specimens referred to asOlisthodiscus luteus maintained in CCAP and UTEX. All the strains examined were similar to one another in appearance and ultrastructural features. They can be accommodated in a single species,H. akashiwo, which has been invalidly published.

In this paper, the genus is validly desribed by providing a Latin diagnosis and designating a type species. Ultrastructural characteristics are also given for the genus.

Key words

Heteroosigma akashiwo Heterosigma inlandica Olisthodiscus luteus Raphidophycean alga Taxonomy Ultrastructure 


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Copyright information

© The Botanical Society of Japan 1987

Authors and Affiliations

  • Yoshiaki Hara
    • 1
  • Mitsuo Chihara
    • 1
  1. 1.Institute of Biological SciencesUniversity of TsukubaIbaraki

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