Morphology, molecular phylogeny and taxonomy of Gonium maiaprilis sp. nov. (Goniaceae, Chlorophyta) from Japan

Abstract

Hayama M., Nakada T., Hamaji T. and Nozaki H. 2010. Morphology, molecular phylogeny and taxonomy of Gonium maiaprilis sp. nov. (Goniaceae, Chlorophyta) from Japan. Phycologia 49: 221–234. DOI: 10.2216/09-56.1

The morphology, molecular phylogeny and taxonomy of Gonium maiaprilis Hayama et al. sp. nov. (Goniaceae, Chlorophyta) were studied using clonal cultured material originating from Fukuoka Prefecture, Japan. This species is similar to G. pectorale O. F. Müller and G. viridistellatum M. Watanabe in having one to three stable pyrenoids in the chloroplasts of eight- or 16-celled vegetative colonies. However, it is distinguished from G. pectorale and G. viridistellatum by the cell arrangement of the eight-celled colonies and from G. pectorale by aplanozygote morphology. Sexual reproduction of G. maiaprilis is heterothallic and isogamous, and the germinating zygote gives rise to a four-cell germ colony. Phylogenetic analyses based on the plastid large subunit of Rubisco genes and sequences for the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (rDNA) (ITS-1, 5.8S rDNA and ITS-2) suggest that G. maiaprilis is separate from other species of Gonium.

Key Words::

• Chlorophyceae
• Goniaceae
• Gonium
• Gonium maiaprilis sp. nov
• ITS
• Molecular phylogeny
• Morphology
• rbcL
• Reproduction
• Taxonomy

ACKNOWLEDGMENTS

We are grateful to Ms. S. Tsuda (University of Tokyo) for her providing soil sample from Fukuoka. This work was supported by Grant-in-Aid for Scientific Research (No. 20247032 to HN) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.