Abstract
The genus Orthoseira Thwaites contains centric diatoms typically inhabiting marginal-aquatic or terrestrial habitats. The high morphological plasticity of representatives of the genus and their occurrence in rarely studied terrestrial habitats complicates an overall assessment of their biodiversity and the distribution of particular species. This study presents a description of four new species of this genus from Southeast Asia and Easter Island. They include: O. radiata M.Rybak, Glushchenko & Kulikovskiy sp. nov., O. distincteareolata M.Rybak, Glushchenko & Kulikovskiy sp. nov., O. cylindrica M.Rybak, Glushchenko & Kulikovskiy sp. nov. and Orthoseira rapanuiensis M.Rybak, Witkowski & Lange-Bertalot sp. nov. Additionally, we attempt to provide a solution to the confused taxonomical history of Liparogyra circularis Ehrenberg and provide the first detailed description of Orthoseira tropica (Krasske) Metzeltin & Lange-Bertalot.
Acknowledgments
The authors are grateful to Professor Georg Zizka for sampling the material from Rapa Nui Island. The authors thank Mr Łukasz Skoczylas for collecting materials for this research and the tardigradologist team from the Jagiellonian University, especially Mr Witold Morek for sharing materials used in this present research.
Disclosure statement
No potential conflict of interest was reported by the author(s).