Australian Tropical Rainforest Plants - Online edition
Trichosanthes odontosperma W.E.Cooper & A.J.Ford
Cooper, W.E. & Ford, A.J. (2010) Austrobaileya 8(2): 126-130. Type: Queensland, COOK DISTRICT: Westcott Road, Topaz, 15 April 2009, W.E.Cooper 2065.
Gourd, Annual; Gourd, Rain Forest; Rain Forest Gourd
Vine stem diameters to 3 cm recorded, young branchlets 5-angular. Subrhytidome layer almost grey. Tendrils unbranched or 2-3 branched.
Leaf simple, unlobed or rarely 3-lobed; blades about 5-19 x 4-16 cm, base cordate or hastate; petioles about 2-9.5 cm long; upper leaf blade smooth, glabrous or with sparse translucent hairs on main veins; underside leaf blade with sparse translucent hairs on main veins and 1-16 circular and flat glands on each side of leaf base.
Male and female flowers on different plants. Male flowers: flowers mostly solitary, rarely a fascicle of two flowers or a raceme beside a solitary flower; peduncles about 3.5-11.0 cm long; flowers about 4.5-9 cm diam.; calyx tube (hypanthium) about 4.5-9 cm long, densely clothed in hairs on the inner surface; calyx lobes 5 (rarely 4), somewhat fleshy and recurved, 8-20 x 2-4 mm; petals 5 (rarely 4), 2.7-5 cm long overall, fringe about 1-1.2 cm long, both the inner and outer surfaces clothed in hairs; stamens 3, two stamens bilocular and one stamen unilocular; stamens free from one another until anthesis when the anthers become fused; anthers S-shaped (sigmoid) about 8-10 mm long, filaments about 1.5 mm long. Pollen orange-yellow. Female flowers: solitary flower; pedicels about 3.1-5 cm long; calyx tube (hypanthium) about 3.9-6.5 cm long; calyx lobes triangular, about 5-12 x 1-2 mm; corolla lobes about 2-3.1 cm long, fringe about 1-1.3 cm long; both the inner and outer surfaces of the corolla lobes clothed in hairs; staminodes three; ovary about 3-3.5 cm long.
Fruits ovoid or ellipsoidal, apex beaked, 9-14 x 6-9 cm, outer surface smooth, orange-green with areas of orange. In transverse section the outer part of the fruit is yellow or orange and of a firm texture while the central part surrounding the seeds is soft and red. Seeds numerous, about 12-18 mm long, zygomorphic, horned, completely enveloped in an aril. Embryo about 9-12 x 5 mm long, cotyledons broad and flat, much larger than the radicle which is only about 1 mm long.
Cotyledons fleshy, recurved, +/- sessile, about 14-23 x 6-9 mm, upper surface hairy at least near the midrib. Cotyledons +/- 3-veined with 1 or 2 veins on each side of the midrib. First pair of leaves palmate, cordate or orbicular, margins coarsely toothed with 12-15 teeth on each side, apex acute or apiculate, base auriculate. Tendrils axillary, usually produced by the third or fourth leaf stage. At the tenth leaf stage: leaf blade cordate or palmately lobed, apex acuminate, base auriculate, margin toothed with about 14-16 teeth on each side. Lateral veins about 3 on each side of the midrib and forming loops inside the blade margin. Both the upper and lower surfaces of the leaf blade densely clothed in short gland-like hairs. Tendrils simple (unbranched) produced near the leaf axils.
Ripe fruit is generally found with a hole pecked in it and the seeds removed and eaten by Victoria's Riflebird. Cooper & Cooper (1994).
Trichosanthes sp. Mount Lewis (B.Gray 167) [HISPID Phrase name].