Sicyos australis
Common names
māwhai
Biostatus
Native
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
Cream, Green
Detailed description
Herbaceous climber; stems annual, up to 10m long, 5-mm diameter, sparsely hirsute with simple multicellular hairs and glandular hairs, glabrescent. Tendrils 3–5-branched. Leaves: petiole 10–65 mm long, scaberulous; lamina ovate or broadly ovate in outline, 35–195 × 45–200mm, cordate with the basal sinus broad, the lobes not overlapping, acuminate, shallowly to deeply palmately 5- or 7-lobed, the lobes broadly triangular, acute or acuminate, margins dentate with apiculate teeth, sparsely scaberulous adaxially and abaxially with simple hairs, more densely and coarsely along veins. Male inflorescence an 8–19-flowered raceme 25–155 mm long; peduncle 15–125 mm long, sparsely scaberulous; rhachis glandular hairy. Male flowers: pedicels 3–11 mm long; hypanthium broadly campanulate, 2.4–2.7 mm diameter; calyx lobes linear, 0.4–0.7 mm long; corolla rotate, 4.5–7.8 mm diameter, mostly glabrous abaxially, the lobe apices puberulous, glabrous adaxially, white, 5-lobed, the lobes broadly triangular–ovate, obtuse; 2.0–2.6 mm long; disc c. 1.2 mm in diameter; staminal column 1.5–1.8 mm long; staminal head 1.7–2.2 mm diameter. Female inflorescence an 8–11-flowered head; peduncle 8–33 mm long. Female flowers: subsessile; ovary ovate, attenuate, c. 3 mm long, 1.4 mm diameter, minutely and densely echinulate with barbed aculei; hypanthium above the constriction broadly campanulate, c. 1.5 mm in diameter, minutely glandular hairy surrounding the disc; calyx lobes linear, 0.4–0.7 mm long; corolla 2.5–3.5 mm diameter, mostly glabrous abaxially, the lobe apices puberulous, glabrous adaxially, white, 5-lobed, the lobes triangular–ovate, obtuse, c. 1.6mm long; disc c. 1 mm in diameter; style c. 1.4mm long; stigma 2-lobed, the lobes c. 0.3mm long, recurved. Fruit ovate, rarely fusiform, 6.4–9.5 × 2.8–4.0 mm, apically attenuate, the surface ± glabrous or scabridulous with short hairs, echinate; aculei dense, 1.6–3.6 mm long, retrorsely barbed. Seeds ellipsoidal, 4.0–5.5 × 2.8–3.4 mm brown.
Similar taxa
In New Zealand could only be confused with Sicyos mawhai. Sicyos australis differs from S. mawhai by the male flowers which are < 10 mm diameter; by the smaller, grey-green 3–5 acutely-lobed leaves; broad leaf sinus (the basal lobes not overlapping this); harsh stem hairs. Both specie of Sicyos have at times been confused with choko (Sechium edule), especially when in a vegetative state. However, choko has larger, darker green leaves, and the fruits of choko are unmistakable, being larger, pear-shaped, pale green, and unadorned with sharp spines.
Distribution
Indigenous. New Zealand: North Island (Northland, Auckland, Waikato and Bay of Plenty). Also Australia and formerly Norfolk and Lord Howe Islands.
Habitat
Coastal forest or lowland forest, often in scrub or amongst bracken fern.
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 | At Risk – Naturally Uncommon | Qualifiers: EF, RR, SO
Threats
Formerly listed under the tag name S. aff. australis (b) (AK 289786; Mangere Stonefields) by de Lange et al. (2009) as a “Coloniser” now that the exact identity of Sicyos australis has been clarified (Telford et al. 2012) this status is still appropriate. It appears that Sicyos australis has recently established in New Zealand, presumably (or at least initially) by natural means. It is now locally distributed over a large part of mainly eastern northern New Zealand and it is actively spreading from these areas into farmland, plantation forestry and urban wasteland. It was assessed in 2017 as ‘At Risk – Naturally Uncommon’ (de Lange et al. 2018). Although it is susceptible to cucumber, watermelon and zucchini mosaic virus, it seems less so than the endemic S. mawhai and it is secure at most known sites.
Detailed taxonomy
Family
Cucurbitaceae
Synonyms
Sicyos angulata L. auct. non. New Zealand authors
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
In suitable conditions flowers are produced throughout the year.
Fruiting
In suitable conditions fruits are produced throughout the year.
Propagation technique
Easily grown from seed. However seed can take several months to germinate.
Other information
Cultivation
Occasionally sold by commercial nurseries.
Plant of the Month
This plant has been featured as a Plant of the Month – see Trilepidea: NZPCN newsletter for August 2004 for the full story.
Etymology
australis: Southern
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.
SICAUS
Chromosome number
2n = c.24, 26
Previous conservation statuses
2017 | At Risk – Naturally Uncommon | Qualifiers: EF, RR, SO
2012 | Non-resident Native – Coloniser | Qualifiers: EF, RR, SO
2009 | Non-resident Native – Coloniser | Qualifiers: EF, RR
2004 | Data Deficient
Referencing and citations
References and further reading
Cameron EK. 1991. Mangere a small forest remnant and Sicyos australis. Auckland Botanical Society Journal 46: 83–84.
de Lange PJ, Norton DA, Courtney SP, Heenan PB, Barkla JW, Cameron EK, Hitchmough RA, Townsend AJ. 2009. Threatened and uncommon plants of New Zealand (2008 revision). New Zealand Journal of Botany 47(1): 61–96. https://doi.org/10.1080/00288250909509794.
Delmiglio C, Pearson MN. 2006. Effects and incidence of cucumber mosaic virus, watermelon mosaic virus and zucchini yellow mosaic virus in New Zealand’s only native cucurbit, Sicyos australis. Australasian Plant Pathology 35: 29–35. https://link.springer.com/article/10.1071/AP05098.
Telford IRH, Sebastian P, de Lange PJ, Bruhl JJ, Renner SS. 2012. Morphological and molecular data reveal three rather than one species of Sicyos (Cucurbitaceae) in Australia, New Zealand, and the islands of the South West Pacific. Australian Systematic Botany 25: 188–201. https://doi.org/10.1071/SB11032.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange 4 January 2004. Description based on Telford et al.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Sicyos australis Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/sicyos-australis/ (Date website was queried)