Species
Picris angustifolia subsp. angustifolia
Etymology
angustifolia: narrow-leaved
Common Name(s)
Native oxtongue
Current Conservation Status
2012 - At Risk - Naturally Uncommon
Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB
Previous Conservation Status
2009 - At Risk - Naturally Uncommon
2004 - Non Resident Native - Coloniser
Qualifiers
2012 - DP, EF, SO, Sp
2009 - SO
Authority
Picris angustifolia DC. subsp. angustifolia
Family
Asteraceae
Flora Category
Vascular - Native
Structural Class
Dicotyledonous Herbs - Composites
Synonyms
Picris attenuata A.Cunn., P. hieracioides var. glabrata Hook.f. In the most recent New Zealand flora treatment all indigenous Picris have been referred to Picris hieracioides L. as species collected here once as a naturalised weed, and to which none of our indigenous species are closely related.
Distribution
Indigenous. North Island where known historically from the Bay of Islands, otherwise still present around the Whangaruru Harbour and on the Hen and Chicken Islands. Also in Australia
Habitat
Open ground and amongst low shrubs and fern in coastal situations and on offshore islands.
Features
Annual to perennial herb 0.4-1 m tall. Stem slender, base woody, usually branched at base or from upper half, dark green. Indumentum of 2-hooked, bristly hairs. Leaves yellow-green. Rosette leaves horizontal, petiolate, lamina 35-300 x 3-30 mm, narrowly ovate, oblanceolate to lanceolate, entire or deeply dentate; stem leaves similar, but fewer, horizontal to suberect, becoming smaller toward plant apex. Lower stem leaves 30-220 x 3-25 mm, upper 7-120 x 0.1-12 mm, terminal leaves bract or thread-like. Inflorescences in corymbose panicles. Capitula numerous, 9-16 mm long, 3-8 mm diam. Involucrum of 18-36 bracts in 2-3 irregular outer and 2 inner rows, at flowering inner bracts clearly longer than outer. Bracts usually with a single line of 2-hooked anchor or bifid hairs along midrib on outer surface. Capitula with 20-60 sulphur yellow flowers. Achenes 5-12.5 mm long, narrowly fusiform. Cuspis 1.2-7.4 mm long. Achene ribs 24-45. Pappus 5-10.5 mm long, pappus rays 45-70.
Similar Taxa
For distinction from oxtongue (Helminthotheca echioides (L.) Holub) see under Picris burbidgeae S.Holzapfel. Picris angustifolia differs from P. burbidgeae chiefly by its involucrum. In this species the bracts are arranged in 2-3 rows, with the longest outer bracts rarely longer than 2/3 length of the innermost bracts (usually much shorter). All the bracts are straight and usually upright. For distinctions between P. angustifolia subsp. angustifolia and subsp. merxmülleri see under Cultural Use
Flowering
October - April
Flower Colours
Yellow
Fruiting
October - May
Propagation Technique
Easy from fresh seed which usually germinates within one to two months. A somewhat unusual plant that is unlikely to prove popular in cultivation, and it can become invasive in some situations.
Threats
Unclear. Like P. burbidgeae this plant is likely to have declined through the spread of more aggressive exotic weeds into the open disturbed habitats it requires. However, we have no direct evidence of this, beyond its apparent loss from the Bay of Islands (where it was first collected in New Zealand). Other than that P. angustifolia subsp. angustifolia seems to be holding its own in the Whangaruru area where it is quite common on some small islands and rocky headlands. Its exact status on the Hen and Chicken Islands is unclear. Whether it is present on the Mokohinau Islands needs confirmation, its presence there is hinted at by the presence of hybrids between it and P. burbidgeae.
Chromosome No.
2n = 10
Endemic Taxon
No
Endemic Genus
No
Endemic Family
No
Where To Buy
Not commercially available
Taxonomic notes
P. angustifolia subsp. angustifolia is distinguished from subsp. merxmülleri Lack et S.Holzapfel by its usually loose panicle. The indumentum of the involucral bracts is usually hispid, with hairs if present usually in more than a single line. Also it differs by the longer achenes and cuspis. The cuspis is from 1/5 – ½ of the total length. In P. angustifolia angustifolia the rosette leaves have usually withered off before flowering.
Attribution
Fact Sheet Prepared by P.J. de Lange (1 November 2009). Description based on Holzapfel & Lack (1993) and fresh specimens.
References and further reading
Holzapfel, S.; Lack, H. W. 1993: New species of Picris (Asteraceae, Lactuceae) from Australia. Willdenowia 23: 181-191.
This page last updated on 7 May 2014