The elegant leek orchid – a new species for Aotearoa

A new species of orchid, the elegant leek orchid, has recently been described and named by botanists from Te Papa and Ōtari Native Botanic Garden. The elegant leek orchid/Manawa Wairepo is found from the central North Island south to the Auckland Islands but is very uncommon and classified as threatened. Curator Botany Carlos Lehnebach and Science Researcher Lara Shepherd introduce us to the new species.

Introducing leek orchids

There are over 150 species of Prasophyllum leek orchids, most of which occur in Australia. Until recently only two species were recognised from New Zealand:

• The swamp leek orchid (Prasophyllum hectoriii) is a rare species found in swamps from the central North Island northwards and the Chatham Islands.
• The leek orchid (Prasophyllum colensoi) is common and widespread throughout Aotearoa and grows in a variety of habitats from the coast to alpine areas.

 A new species hiding in plain sight

The leek orchid is known for its remarkable variability in flower forms, leading orchid experts to speculate that some of these forms might belong to different species. Our goal was to test this idea using DNA and morphological analysis.

The results were clear – two genetically and morphologically distinct species were identified within what was previously considered a single species of leek orchid. Remarkably, these species sometimes even grow side by side! The more common species retains the name Prasophyllum colensoi, while the newly described, rarer species has been christened the elegant leek orchid or Prasophyllum elegantissimum. The scientific name reflects the plant’s graceful and slender appearance, setting it apart from its more common counterpart.

The te reo name, Manawa Wairepo, was gifted by Ngāti Maru. ‘Manawa’ comes from Manawa-kawa, another orchid species that was discovered nearby in the Tāngarākau Gorge and named by both Ngāti Maru and Ngāti Hāua. ‘Wairepo’ represent the orchids preferred environment, swamp with the word wai added to capture the orchards natural beauty, grace, and elegance.

A rare treasure

The elegant leek orchid is known from the central North Island, through the South Island to Stewart Island and the Auckland Islands. Despite its widespread distribution, herbarium collections and iNaturalist records reveal that this species is exceedingly rare. This scarcity underscores the importance of conservation efforts to protect and preserve this species.

Download the free e-print of the article: Lehnebach CA, Alderton-Moss J, Shepherd LD (2025) A new species of Prasophyllum (Orchidaceae) for New Zealand and lectotypification of P. colensoii. New Zealand Journal of Botany.

Acknowledgements

We are grateful to those who helped us in the field, sent plant material, and/or allowed collection from their properties. We also thank staff from other herbaria from New Zealand and overseas (AK, CANB, CHR, E, K, MEL and WELT) for their assistance. This study was funded by a grant from the Australia and Pacific Science Foundation awarded to Carlos Lehnebach and Lara Shepherd [grant number APSF19047].