Tetrastigma thorsborneorum Jackes
Jackes, B.R. (1989) Austrobaileya 3(1): 155. Type: Queensland, Gustav Creek, Nelly Bay, Magnetic Island, 19 09 S, 146 51 E, 15 March 1985, B.R.Jackes; holo: BRI; iso: A, CANB, K, L, MEL, NSW.
Vine stem diameters to 5 cm recorded. Stem vessels large, readily visible to the naked eye.
Compound leaves bipinnate with 7-9 leaflets. Leaflets about 6-12.5 x 2.5-6 cm, lateral leaflet stalks about 0.3-0.8 cm long. Stalks of the terminal leaflets about 3 cm long, longer than those on the lateral leaflets. Leaflet blades serrate, usually with 2-4 teeth on each side, mainly towards the apex. 'Oil dots' elongated. Tendrils usually branched and leaf opposed. Oak grain in the twigs.
Male flowers: Inflorescence about 3-5 cm long. Calyx about 0.5 mm long. Petals about 2 x 1.5 mm, apex hooked or hooded. Petals strongly reflexed at anthesis. Staminal filaments about 1.5 mm long, anthers about 0.5 mm long. Female flowers: Inflorescence about 3.5-7 cm long. Pedicels about 3 mm long. Calyx about 0.5 mm long. Petals about 2.5 x 1.5 mm. Staminodes present. Ovary broadly conical, about 1.5 mm long, stigma sessile, 4-lobed. Ovary 2-locular. Ovules 2 per locule. Fide Jackes (1989).
Fruits shiny, globose or ellipsoid, about 15 x 12 mm, flesh burnt orange. Seeds globose to ellipsoid, about 7-11 x 6-7 mm, testa surface sculptured. Embryo white, about 2.5-4 mm long. Cotyledons broadly lanceolate, about 1-2 mm long. Radicle about 1-2 mm long. Cotyledons about as long as, but wider than the radicle.
Cotyledons ovate, about 37-45 x 21-31 mm, apex acute or obtuse, base cordate, +/- three-veined or with an intramarginal vein, midrib raised on the upper surface. First pair of leaves simple, ovate to elliptic, about 8-9 x 5-6 cm, margins sparsely toothed with three or four teeth on each side, midrib raised on the upper surface. Stipules broadly triangular, about 2 mm long. Third leaf trifoliolate. At the tenth leaf stage: leaf compound, pedate with five or six leaflets, middle or terminal leaflet larger than the laterals. Leaflet blades elliptic or elliptic-obovate, apex acuminate, base cuneate or oblique. Lateral veins about 4-6 on each side of the midrib. Margins serrate with two to five teeth on each side. 'Oil dots' elongated to some extent. Stipules broadly triangular, about 3 mm long. Tendrils leaf-opposed, two-branched. Seed germination time 41 to 72 days.