Craspedia argentea
Common name
Pisa Flats woollyhead
Synonyms
None - first described in 2022.
Family
Asteraceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledonous composites
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) – more information about this can be found on the NZTCS website. This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. 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. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Threatened – Nationally Critical | Qualifiers: DP, OL
Brief description
Rosette-forming herb with silvery grey, elliptic, obovate, spatulate to oblanceolate leaves. Leaf hairs appressed to floccose arranged in a wavy in pattern. Flower heads (capitula) on stems up to 130 mm tall. Flower head yellowish-white, with dark red-purple anthers.
Distribution
Endemic. New Zealand: South Island (Central Otago, Pisa Flats, Mahaka Katia Scientific Reserve).
Habitat
Known only from a 25-ha area of gravelly outwash terrace, on crest and top slope of scarp; where it grows in well-drained ground with a firm, pebbly surface and fine, silty soil at 210 m above sea level near Lake Dunstan (a hydroelectric dam) (Breitwieser & Ford 2022).
Similar taxa
Allied to Craspedia lanata from which it differs by the rosette leaves which are mostly shorter than 50 mm, and covered with a dense, appressed to floccose, lanate indumentum. The florets also differ in that they have yellowish-white corolla and dark red-purple anthers (Breitwieser & Ford 2022).
Flowering
Early October – mid November.
Flower colours
Yellow, White
Fruiting
Late November through December.
Threats
Craspedia argentea as Craspedia (a) (CHR 511522; Clutha River) has been assessed as ‘Threatened/Nationally Critical’ (Criteria A1, Population <250 mature individuals, with a decline rate of 10%–30%), qualified ‘DP’ (Data Poor), ‘OL’ (One Location) by the New Zealand Indigenous Vascular Plant Threat Listing Panel (de Lange et al. 2018). Since then the qualifiers for the New Zealand Threat Classification System manual 2008 have been revised and expanded (see Rolfe et al. 2021). Using the revised qualifiers Barkla (2021) recommended that the qualifiers OL (One Location), DPT (Data Poor: Trend) and CR (Conservation Research Needed) be applied because of restriction of C. argentea to Mahaka Katia Scientific Reserve, the lack of adequate trend data, and the need for research to better understand the causes of decline and solutions for recovery (see also Breitwieser & Ford 2022). These adjustments have yet to be ratified by the New Zealand Indigenous Vascular Plant Threat Listing Panel.
Etymology
craspedia: Craspedia is named for the Greek ‘Kraspedon’, meaning an edge, hem or border, because of the woolly fringes of the leaves of the type species.
argentea: Silvery
Extra information
See brief article in July 2022 Trilepidea Four new species of woollyhead (Craspedia) described from the eastern South Island (p. 2).
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 17 July 2022. Adapted from Breitwieser & Ford (2022).
References and further reading
Barkla J. 2021. Understanding the conservation status of Central Otago dryland plants believed to be imminently threatened with extinction. Contract Report No. 6691934. Prepared for the Department of Conservation, Dunedin.
Breitwieser I, Ford KA. 2022. Four new species of Craspedia (Compositae/Asteraceae, Gnaphalieae) from the South Island of New Zealand, all characterised by dark red-purple anthers. New Zealand Journal of Botany. https://doi.org/10.1080/0028825X.2022.2095919
de Lange PJ, Rolfe JR, Barkla JW, Courtney SP, Champion PD, Perrie LR, Beadel SM, Ford KA, Breitwieser I, Schönberger I, Hindmarsh-Walls R, Heenan PB, Ladley K. 2018. Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series 22. Department of Conservation, Wellington, NZ. 82 p. https://www.doc.govt.nz/globalassets/documents/science-and-technical/nztcs22entire.pdf
Rolfe J, Makan T, Tait A. 2021. Supplement to the New Zealand threat classification system manual 2008: new qualifiers and amendments to qualifier definitions. Department of Conservation, Wellington, NZ. 9 p. https://www.doc.govt.nz/globalassets/documents/science-and-technical/nztcs-supplement-2021.pdf.