The New Zealand Plant Conservation Network

Species

Sicyos australis

Etymology

australis: southern

Common Name(s)

mawhai

Current Conservation Status

2018 - 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

2012 - Non Resident Native - Coloniser
2009 - Non Resident Native - Coloniser
2004 - Data Deficient

Qualifiers

2012 - EF, RR, SO
2009 - EF, RR

Authority

Sicyos australis Endl.

Family

Cucurbitaceae

Flora Category

Vascular - Native

NVS Species Code

SICAUS

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

Sicyos angulata L. auct. non. New Zealand authors

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.

Features

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.

Flowering

In suitable conditions flowers are produced throughout the year.

Flower Colours

Cream,Green

Fruiting

In suitable conditions fruits are produced throughout the year.

Propagation Technique

Easily grown from seed. However seed can take several months to germinate.

Threats

Previously 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. 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.

Chromosome No.

2n = c.24, 26

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

This page last updated on 19 Dec 2014