Convolvulus waitaha
Common names
grass convolvulus
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Lianes & Related Trailing Plants - Dicotyledons
Flower colours
White
Detailed description
Rhizomatous, lianoid, decumbent, spreading perennial herb. Stems, spreading, often ascending, up to 800 mm long, sparse to densely covered in retrorse hairs. Leaves in rosettes and alternate on stems 6-17 x 5-12 mm, deltoid, deltoid-ovate, to broad-oblong, green; glabrous or with scattered hairs near lamina/petiole junction, margins entire to undulate, irregularly lobed, base truncate, rarely oblique; apex retuse rarely obtuse to subacute. Pedicel 8-18 mm long, sparsely hairy. Sepals 3.6-4 x 2.1-2.6 mm, obovate to ovate, green both surfaces glabrous. Corolla 10-16 mm wide when open, white, comprising five fused lobes, mid-petalline band green. Capsule 5-6 x 5-6.5 mm, papery, globose, with 2-4 seeds. Seeds broadly obovate 3.1-3.9 x 2.3-3.3 mm, brown, with grey nut-brown. Surface covered in distinct butr irregular ridges and tubercules.
Similar taxa
Convolvulus verecundus Allan and C. fracto-saxosa Petrie, from which it is distinguished by longer lianoid stems (up to 800 mm); usually glabrous, green leaves; corolla > 18 mm diam., when open; the pale green mid-petaline band; and by the seed coat being densely covered in distinct irregular tubercules and ridges.
Distribution
Endemic. Easterly in the North Island and South Island. In the North Island known from an old record from the Hawke’s Bay, otherwise from Cape Palliser west to Tongue Point. In the South Island it occurs from Marlborough south to Otago.
Habitat
Coastal to lowland (1 - 500 m a.s.l.), almost, but not strictly coastal. A species of short tussock grassland, introduced lightly browsed pastures, boulder banks, talus slopes and amongst fine gravel. It frequently grows with and tolerates introduced grasses and herbs.
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.
- 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
Threats
Not Threatened, though it has declined from the North Island, and is now only known with certainity from the vicinity of Cape Palliser.
Detailed taxonomy
Family
Synonyms
Convolvulus verecundus subsp. waitaha Sykes
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
October - February
Fruiting
December - March
Life cycle and dispersal
Seeds are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easy from fresh seed. Plants grow best in well drained, fertile soils in full sun, and make an excellent pot plant. This species does not thrive in humid climates.
Other information
Etymology
convolvulus: From Latin convolvere, which means to twine around
waitaha: Named for the location in Canterbury, from the Maori wai ‘water’ and taha ‘to pass to one side’, meaning a backwater.
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.
CONWAI
Chromosome number
2n = 22
Previous conservation statuses
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.
- 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.
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | Regionally Not Threatened
Referencing and citations
References and further reading
Reed, A. W. 2002: The Reed Dictionary of New Zealand Place Names. Reed Publishing. Auckland.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009: Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309.
Attribution
Fact sheet prepared by P.J. de Lange for NZPCN (1 June 2013)
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Convolvulus waitaha Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/convolvulus-waitaha/ (Date website was queried)