Parablechnum triangularifolium
Common name
kiokio, Green Bay kiokio
Synonyms
Lomaria capense var. carsi Dobbie; Blechnum triangularifolium T.C.Chambers et P.A.Farrant
Family
Blechnaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Ferns
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.
BLETRI
Chromosome number
2n = 56
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2012 | Not Threatened
Previous conservation statuses
2009 | Not Threatened
2004 | Not Threatened
Distribution
Endemic. North, South and Chatham Islands. In New Zealand proper recorded from North Cape south to Napenape (North Canterbury) and near Okarito (Westland)
Habitat
Coastal to montane, although this species is mostly found in coastal and lowland situations. Blechnum triangularifolium is a basicolous species frequenting base-rich substrates such as calcareous silt and mudstones, sandstones, limestone, marble, basalt and basaltic andesite, it also grows on the ultra basic serpentinite rocks at North Cape. In these habitats it is often found growing within seepages with such plants as Machaerina sinclairii. In karst country it may extend a considerable distance inland and it has been collected on a few occasions from calcareous rocks in montane forest.
Features
Rhizome short-creeping to erect; clothed with the bases of old stipes and a dense mass of scales; scales to 12 × 2 mm, lanceolate, acuminate, light brown, reddish brown, or sometimes bicolorous, entire or minutely toothed. Fronds dimorphic, usually pendulous, 0.3-0.900 × 0.09-0.55 m, widest at base of lamina; fertile fronds smaller than sterile fronds. Stipe 0.15-0.73 m, fertile stipes similar in length or longer than stipes of sterile fronds, up to 10 mm in diameter at the base, stramineous to pale brown, darkening only at the very base, stipes scaly especially at base, upper stipes almost glabrous at maturity; scales up to 10.0 × 1.0-1.5 mm wide, ovate, cordate or linear, acuminate, often appressed, brown concolorous or “black-spot”, shiny, entire or finely toothed. Lamina broadly deltoid, pale green, 1-pinnate, 8-33 pairs of pinnae. Rachis and costae pale brown or reddish brown with sparse to moderately dense scales and some irregular small fine hairs; scales mostly small, up to 3.0 × 1.5 mm, ovate to cordate, peltate, appressed, shortly acuminate, shiny and bicolorous with “black-spot”, entire or finely toothed (these scales usually especially conspicuous on abaxial costae); also some larger scales, up to 10 × 1 mm, narrow, linear, acuminate, twisted, concolorous pale brown or reddish brown, entire or finely toothed. Sterile pinnae 70-250 × 14-20 mm, lanceolate-linear, slightly falcate, acuminate to attenuate at apices, rounded or tapering acutely to rachis; shortly petiolate or sessile at base of lamina becoming basiscopically adnate then sometimes fully adnate towards the apex of the lamina; coriaceous to papery; margins finely serrate, often crenate or undulate, toothed with glandular vein ending and brown cartilaginous marginal tissue; veins simple or once-furcate; scales on mature pinnae not extending to surface of lamina; basal pinnae slightly longer or similar to pinnae pair above and longer than middle pinnae, sometimes deflexed, auricles and auriculate pinnae bases absent; terminal pinna usually a little longer than subterminal. Fertile pinnae 110-240 × 3-6 mm, narrow, linear, shortly petiolate at the base becoming basiscopically adnate and winged towards the apex; basal pinnae not reduced; sori covering under surface except for sterile attenuate apices and small sterile lobes that occur at the base of the lowermost pairs of pinnae in some specimens; spores 46-64 × 29-50 µm.
Similar taxa
Parablechnum triangularifolium is superficially similar to P. novae-zelandiae, from which it is easily distinguished by the deltoid, pale green almost glabrous fronds which lack auricles, and by the pinnae which get longer towards the frond base, and are distinctly falcate and upward-pointing. From Parablechnum montanum, P. triangularifolium can be distinguished by its ecological preferences and habit of growing at lower altitudes, most usually in coastal situations, and by the broadly deltoid, pale green fronds which are 0.09-0.55 m wide at the base, bearing 8-33 pairs of pinnae, and by the acuminate to attenuate pinnae apices. From Parablechnum procerum it can be distinguished by the same characters but also by the abaxial costae, rachis, and stipe which are bicolorous abyd by the scales which have prominently black-spotted centres, rather than mostly concolorous, shiny, dark reddish brown (rarely slightly bicolorous with paler margins (though never, ever furnished with a central “black spot”))
Flowering
Not applicable - spore producing
Flower colours
No flowers
Fruiting
Not applicable - spore producing
Propagation technique
Very easily grown from fresh spore and young plants which transplant readily. Parablechnum triangularifolium is an attractive fern that does well in a pot or planted in a sunny, moist but free draining fertile soil. It responds well to regular applications of lime. Although reasonably hardy it dislikes long periods of drought and frosts.
Taxonomic notes
Perrie et al. (2014) advocated for a broadened circumscription of Blechnaceae whereby a number of genera traditionally recognized as distinct from Blechnum were merged within it. However, this view has not met with universal acceptance (see Gasper et al. 2016) and does not seem to be followed worldwide (PPG 2016). From a New Zealand perspective the decision to merge Doodia in Blechnum, and rejection of Diploblechnum has not been universally accepted either e.g., Wilcox & Warden (2017), and as such it is considered appropriate to follow world opinion and accept the taxonomy of Gasper et al. (2016) and recommendations of the PPG (2016). See also the comments by Pyner (2017).
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (7 March 2012). Description adapted Chambers & Farrant (1998)
References and further reading
Chambers, T.C.; Farrant, P.A. 1998: The Blechnum procerum (“capense”) (Blechnaceae) complex in New Zealand. New Zealand Journal of Botany 36: 1-19.
Gasper, A.L.; de Oliveira Dittrich, V.A.; Smith A.R.; Salino, A. 2016: A classification for Blechnaceae (Polypodiales: Polypodiopsida): New genera, resurrected names, and combinations. Phytotaxa 275: 191–227.
Perrie, L.R.; Wilson, R.K.; Shepherd, L.D.; Ohlsen, D.J.; Batty, E.L.; Brownsey, P.J.; Bayly, M.J. 2014: Molecular phylogenetics and generic taxonomy of Blechnaceae ferns. Taxon 63(4): 745-758.
PPG 1: The Pteridophyte Phylogeny Group 2016: A community-derived classification for extant lycophytes and ferns. Journal of Systematics and Evolution 54: 563-603.
Pyner, T. 2017: A new classification of Blechnum. British Pteridological Society. https://ebps.org.uk/new-classification-blechnum/
Wilcox, M.; Warden, J. 2017: Botany of Hillsborough coast bush reserves, Manukau Harbour, Auckland. Auckland Botanical Society Journal 72: 32-46.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Parablechnum triangularifolium Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/parablechnum-triangularifolium/ (Date website was queried)