Zehneria cunninghamii F.Muell.

Cucurbitaceae

Mueller, F.J.H. von  (1856) Hook. J. Bot. Kew Gard Misc.: 50. Type: Lecto: Qld, Moreton Bay, F. Muell. s. n., (TCD). Fide de Wilde & Duyfjes (2006).

Cucumber, Slender; Slender Cucumber

A slender vine not exceeding a stem diameter of 2 cm.

Leaf blades +/- triangular to ovate, about 3-13 x 2.2-12 cm, petioles about 1-2 cm long, twisted and curved, particularly towards the base, deeply grooved on the upper surface. Leaf blade margins with 10-20 teeth on each side. Upper surface of the leaf blade scabrous, densely clothed in short stiff hairs. Lower surface similar to the upper surface but the hairs more scattered. Midrib raised in a depression on the upper surface. Tendrils simple (unbranched), leaf-opposed.

Flowers on long pedicels. Male flowers: Flowers about 15 mm long, calyx lobes minute, corolla lobes about 2-3 mm long. Female flowers: Flowers about 30 mm long and 7-8 mm diam. Sepals about 0.8-1 mm long. Corolla lobes about 2-3 mm long. Staminodes 3. Ovary about 2.5-3 mm long. Style ending in a green stigma.

Fruits globose, about 7-9 mm diam., apex apiculate because of a persistent style about 1 mm long. Fruit surface marked by about 8 longitudinal lines. Seeds about 20 per fruit, obovoid, about 3-4 mm long. Cotyledons much longer and wider than the radicle which is about 0.8 mm long.

Cotyledons elliptic to orbicular, about 11-14 x 8-13 mm, apex retuse, base obtuse, petioles very short or absent. Cotyledons +/- three-veined, at least at the base but venation rather obscure. Upper surface minutely scabrous from pale-coloured tubercles or hair bases. First leaf +/- triangular to cordate, about 3.5 x 3.5 cm, apex acuminate, base shallowly cordate to truncate, margin coarsely dentate, petioles about 1.5 cm long. At the tenth leaf stage: leaf blade +/- three to five-lobed, the middle lobe much longer than the lateral lobes, leaf blade about 3-4 x 2.5-3 cm, apex apiculate, base +/- cordate. Oil dots visible with a lens. Upper surface minutely scabrous from pale-coloured tubercles or hair bases, lower surface sparsely clothed in pale-coloured hairs, mainly along the veins. Venation palmate. Midrib raised on the upper surface. Margin with 10-15 teeth on each side. Petiole about 8 mm long. Tendrils simple (unbranched) arising near the leaf axils. Taproot thickened, emitting an odour like that of cucumber (Cucumis sativus) when crushed. Seed germination time 12 to 16 days.

Endemic to Australia, occurs in CYP, NEQ, CEQ and southwards as far as north-eastern New South Wales. Altitudinal range in NEQ from near sea level to 1100 m. Grows in monsoon forest, lowland, upland and mountain rain forest.

Melothria cunninghamii (F.Muell.) Benth., Flora Australiensis 3: 320(1867). Melothria cunninghamii (F.Muell.) Benth. var. cunninghamii, Bibliotheca Botanica 89(4): 1189(1928). Melothria cunninghamii var. major Domin, Bibliotheca Botanica 89(4): 1189(1928), Type: Nordost-Queensland: Regenwalder bei Allumbah (= Yungaburra) (DOMIN II. 1910). Holo: PR. Neoachmandra cunninghamii (F.Muell.) W.J.de Wilde & Duyfjes, Blumea 51: 18 (2006).