Ipomoea saintronanensis R.W.Johnson

Johnson, R.W. (1984) Austrobaileya 2(3): 222. Type: Queensland, 40 Mile Scrub, 21 Feb. 1986, J.R. Clarkson 6332; holo: BRI; iso: CANB, DNA, K, MEL, MO, QRS, PERTH.

Morning Glory

Vine stem diameters to 4 cm recorded. Blaze odour mousy, resembling that of acetamide or freshly mixed araldite.

Leaf blades about 8-15 x 6-17 cm, petioles about 3-12 cm long. Underside of the leaf blade clothed in pale prostrate hairs. Twig bark often very pale brown. Lenticels usually prominent on leafy twigs.

Flowers large, about 10-12 x 8-11 cm. Sepals about 30 x 25 mm, tightly clasping the base of the corolla tube. Staminal filaments about 11 cm long, hairy towards the base, attached to the inner surface of the corolla tube about 1-1.5 cm from the base. Stigma bilobed.

Fruits globose, about 2-2.5 x 1.5-1.8 cm, +/- enclosed in the persistent sepals. Seeds up to 4 per fruit, each seed globular, about 9-10 x 4 mm, clothed in woolly hairs about 6-10 mm long. Cotyledons bilobed, folded and rolled with endosperm included in the folds. Testa intruding into the cotyledons by way of one ridge only. Radicle about 3-3.5 mm long, shorter and narrower than the cotyledons.

Cotyledons about 40-75 x 37-60 mm, deeply bilobed at the apex, base auriculate, petioles about 20-50 mm long. Cotyledons 3-5-veined from the base and the midrib does not extend to the apex. Hypocotyl lenticellate. First leaves cordate, apex acuminate, base cordate, leaf blades sparsely hairy on the underside. At the tenth leaf stage: leaf blade cordate, apex shortly acuminate, base cordate. Midrib raised in a depression on the upper surface of the leaf blade. Lower surface of the leaf blade densely clothed in translucent, appressed hairs and numerous minute, pale-coloured, spherical glands. Two raised glands present on the underside of the petiole near its junction with the leaf blade. Stems twining. Taproot massive, very swollen. Seed germination time 8 to 47 days.

Endemic to NEQ. Altitudinal range from 600-900 m. Grows in vine thicket and monsoon forest.