Kew Bulletin

, 73:53 | Cite as

Two new species of Hydrobryum (Podostemaceae) from Laos

  • Satoshi KoiEmail author
  • Masahiro Kato


Two new species of Podostemaceae are described from a single site in northern Central Laos. Hydrobryum hapteron is characterised by the many long holdfasts in the basal area of the crustose root and the long stalks of capsules. It shares the prominent holdfasts and stalks of capsules with H. ramosum (C. Cusset) Koi & M. Kato but is distinct from it in the crustose root. Hydrobryum subcylindricoides is similar to H. subcylindricum Koi & M. Kato in the ribbon-like root but differs from it in the wider root, Y-shaped stigmas and fewer ribs on the capsule.


Holdfast Hydrobryum hapteron Hydrobryum subcylindricoides Laos Phou Khao Khouay taxonomy 



We thank P. Werukamkul for her collaboration with field work and two reviewers for the useful comments. This study was supported by a JSPS KAKENHI Grant (No. 26870502 to SK).


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Copyright information

© The Board of Trustees of the Royal Botanic Gardens, Kew 2018

Authors and Affiliations

  1. 1.Botanical Gardens, Faculty of ScienceOsaka City UniversityOsakaJapan
  2. 2.Department of BotanyNational Museum of Nature and ScienceTsukubaJapan

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