Sticherus flabellatus var. flabellatus
Common names
umbrella fern
Biostatus
Native
Category
Vascular
Structural class
Ferns
Detailed description
Colonial yellow-green to green umbrella fern. Fronds erect 1–1.4 m tall, rather glossy above, dull below. Stipes 0.2–0.6 m long, pale brown, glabrous, rather wiry. Rachises in 1–(2) tiers, each forking 2–3 times, 100–300 mm from the stipe to the tip of the longest branch, erect and spreading, flabellate, glabrous or slightly scaly. Pinnae linear up to 40 × 3 mm, apex acute, glossy yellow-green to green above paler beneath. Sori in one row either side of the midrib but away for the pinna margins, 4–5 sporangia in each, without indusia. (Description adapted from Chinnock & Bell (1998)).
According to Brownsey et al. (2013), “Sticherus flabellatus has fronds that are held partially upright in the form of a fan, rather than drooping like an umbrella. There is a very narrow angle (mean 30°) between paired proximal costae. The ultimate leaflet is much longer than the proximal costa (mean ratio 15.5 : 1). The proximal costa usually lacks leafy ultimate segments. The ultimate leaflet is narrowly elliptic in outline with the segments arising at 50–60° to the costa. The segments of the ultimate leaflet are longest near the middle, 20–40 mm long, 1.5–2 mm wide, minutely serrate along the margins, and green on the underside. There are occasional, very narrow, fimbriate, brown scales along the costae, and hair-like scales on the undersurfaces. Spores measure 32–35 mm by 17-19 mm (four samples from four populations).”
Similar taxa
Rather distinctive, the broad, fan-shaped, yellow-green to green concolorous fronds serve to distinguish it from the only other common Sticherus in New Zealand, S. cunninghamii (Hook.f.) Ching, which has much more divided fronds, with shorter pinnules dark green above and whitish beneath. Its pinnae are also markedly more scaly. Distinction from the little known (in New Zealand) S. tener (R.Br.) Ching is less clear, but this species has its pinnae arising at right angles to the rachis branches.
Distribution
Indigenous. In New Zealand known from scattered locations from North Cape south to the Karangahake Gorge. Probably most common on Great Barrier Island (Aotea Island).
There has been some confusion over the distribution of Sticherus flabellatus in New Zealand. Perrie (2013) stated: “Populations of Sticherus tener and Sticherus urceolatus in the northern South Island had previously been mistakenly attributed to Sticherus flabellatus. We now believe that Sticherus flabellatus does not occur in the South Island, but it is common in the northern North Island.”
Common in Australia.
Habitat
Coastal to lowland. In the North Island usually associated with kauri (Agathis australis) forest, and/or regenerating forest and scrub nearby established kauri forest remnants. It also grows along steep sided streams and on rocks within gorges.
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 | Not Threatened | Qualifiers: SO
Threats
Not actively threatened. However, with the exception of Great Barrier Island (Aotea Island) it is never common anywhere, and some populations are very small and vulnerable to land clearance and mining.
Detailed taxonomy
Family
Gleicheniaceae
Synonyms
Gleichenia flabellata R. Br.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Propagation technique
Can be grown from rooted pieces and fresh spores. However, spores can be very tricky to raise and plants resent root disturbance. Nevertheless, once established this species is one of the few members of the New Zealand Gleicheniaceae that is easily maintained in cultivation.
Other information
Etymology
sticherus: In rows; from the greek sticheres; arrangement of the spore clusters
flabellatus: Fan shaped; from the Latin flabellum; shape of the leaves
Chromosome number
2n = 68
Previous conservation statuses
2017 | Not Threatened | Qualifiers: SO
2012 | Not Threatened
2009 | Not Threatened | Qualifiers: SO
2004 | Sparse
Referencing and citations
References and further reading
Brownsey PJ, Ewans R, Rance B, Walls S, Perrie LR. 2013. A review of the fern genus Sticherus (Gleicheniaceae) in New Zealand with confirmation of two new species records. New Zealand Journal of Botany 51(2): 104–115. https://doi.org/10.1080/0028825X.2013.773917
Chinnock RJ, Bell GH. 1998. Gleicheniaceae. Flora of Australia 48, Ferns Gymnosperms and allied groups: 148–162. ABRS/CSIRO Victoria, Australia.
Perrie L. 2013: Would you mine a rare population? Blog on the Museum of New Zealand/Te Papa Tongarewa website. https://blog.tepapa.govt.nz/2013/04/21/would-you-mine-a-rare-population/
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (January 2005). Description adapted from Chinnock & Bell (1998). Updated by Melissa Hutchison (19 November 2022), with reference to Brownsey et al. (2013).