Round-leaved half star Sebaea ovata

Key Features

  • A short-lived, stiffly erect herb with single or sparingly branched, four angled stems up to 25 cm tall. Small, green, unstalked, oval leaves up to 1.5 cm long occur in distant pairs along the stem. Small yellow flowers occur in terminal clusters and give rise to small capsules.

Distribution and Habitat

  • Originally found from Northland to Canterbury, but the only recent records are from the southern North Island. Habitat is open ground in coastal and lowland swampy ground and ephemeral wetlands, including those in dune hollows.


  • Habitat modification and loss.
  • Competition with exotic plants.
  • Browse by caterpillars.
  • Trampling by stock.

Management Opportunities

  • Survey for new locations.
  • Mark known sites.
  • Protection of habitat.
  • Re-establish in appropriate sites in plantation forests on dunes.
  • Restrict access by stock.

Monitoring Options

  • Check existing populations annually.
  • Report new locations to DOC, NZPCN.

Further Information and Support

  • New Zealand Plant Conservation Network (NZPCN).
  • Weed management - Department of Conservation, Regional Councils
  • References
    • Dopson, S.R.; de Lange, P.J.; Ogle, C.C.; Rance, B.D.; Courtney, S. & Molloy, J. (1999). The conservation requirements of New Zealand’s nationally threatened vascular plants. Threatened Species Occasional Publication 13. Department of Conservation, Wellington.
    • Johnson, P.N. & Brooke, P.A. (1989). Wetland plants in New Zealand. DSIR Publishing, Wellington.
    • Peter de Lange, Peter Heenan, David Norton, Jeremy Rolfe and John Sawyer (2010). Threatened Plants of New Zealand. Canterbury University Press, Christchurch. 472 pp.