Rhopalostylis baueri
Common names
Kermadec nīkau (N.Z. only)
Biostatus
Native
Category
Vascular
Structural class
Trees & Shrubs - Monocotyledons
Simplified description
Palm to 15 m tall with a ringed trunk and 3 m-long leaves inhabiting Raoul Island in the Kermadec Islands. Leaves with multiple long narrow leaflets (to 1 m long) closely-spaced along the central stem. Flowers pinkish, in multiple spikes at the top of trunk. Fruit red.
Flower colours
Red/Pink, White
Detailed description
Trunk up to 15 m tall, and 0.35 m wide, green to dark green fading to grey with age between rather closely spaced leaf-scars; crown-shaft to 0.80 m long, smooth and green, slightly bulging. Leaf to 3 m long, usually dark green; leaflets closely set, ascending sharply, up to 1 m long and 40 mm wide. Spathes c. 380 × 150 mm, between pink and yellow, smooth, falling as first flowers open. Inflorescence: Ultimate branches of inflorescence to 300 mm long, c. 15 mm diameter with buds on, at first pale cream-coloured; flower-buds tightly packed. Sepals short, the longest one in male rarely = petals. Petals white or pink. Fruit c. 13 × 12 mm, subglobose to globose brick-red. Seed almost spherical, tightly invested in pale fawn endocarp which is marked by several vascular strands curving ± obliquely from hilum and only a few running longitudinally; hilum a broad band from the slightly flattened chalazal area to a pronounced papilla beside the micropyle.
Similar taxa
Rhopalostylis sapida is a very variable species. It is best distinguished from R. baueri by its elliptic-oblong, smaller (mostly up to 7 mm diameter) fruit. While many New Zealand populations of R. sapida have narrower leaflets, some, especially those in the Hauraki Gulf and on the Chatham Islands have equally broad leaflets and fruit dimensions comparable to R. baueri. Rhopalostylis sapida is absent from the indigenous range of R. baueri.
Distribution
Indigenous. In New Zealand known only from Raoul Island (Kermadec Islands group). Also on Norfolk Island, its type locality.
Habitat
Abundant in both dry and wet forest types on Raoul Island where it sometimes is the main canopy dominant.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | At Risk – Naturally Uncommon | Qualifiers: RR, SO
Threats
In the New Zealand part of its range it does not face any specific threats. However, it is known only from Raoul Island, and so qualifies as At Risk – Naturally Uncommon. On Norfolk, while common it occupies a very reduced range in the centre of that island. There the species is threatened to some extent by rats which eat the fruit and germinating seedlings.
Detailed taxonomy
Family
Arecaceae
Synonyms
Areca sapida Endl., Kentia sapida (Endl.) Mart., Kentia baueri Seem., Eora baueri (H.Wendl. et Drude) O.F.Cook., Rhopalostylis cheesemanii Beccari, R. baueri var. cheesemanii (Beccari) Sykes
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
December–January
Fruiting
December–January
Propagation technique
Easily grown from fresh seed. Seed should be soaked in water to remove flesh and then sown over a damp peat/coarse sand mix and left in a shaded spot (ideally in a mister) and ignored. Fruit may take up to a year to germinate. Frost tender. Plants resent root disturbance so they should be planted in a sheltered semi-shaded site and then left alone.
Other information
Cultivation
Occasionally sold by retail plant nurseries and most specialist native plant nurseries, usually under the names R. cheesemanii and R. baueri var. cheesemanii. Most material sold here as R. baueri is from Norfolk Island.
Etymology
rhopalostylis: Club style
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
RHOBAU
Chromosome number
2n = 32
Previous conservation statuses
2017 | At Risk – Naturally Uncommon | Qualifiers: RR, SO
2012 | At Risk – Naturally Uncommon | Qualifiers: RR, SO
2009 | At Risk – Naturally Uncommon | Qualifiers: TO
2004 | Range Restricted
Referencing and citations
References and further reading
Moore LB, Edgar E. 1970. Flora of New Zealand, Volume II. Indigenous Tracheophyta: Monocotyledones except Gramineae. Government Printer, Wellington, NZ. 354 p.
Attribution
Description adapted from Moore and Edgar (1970).
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Rhopalostylis baueri Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/rhopalostylis-baueri/ (Date website was queried)