Marsdenia pleiadenia (F.Muell.) P.I.Forst.

Apocynaceae

Forster, P.I. (1995) Australian Systematic Botany 8: 804.

Vine stem diameters to 4 cm recorded. Xylem (wood) produced in irregularly shaped segments which are surrounded or separated from one another by granular rays of tissue. Dead bark shows layers or growth rings in transverse section.

Twigs, petioles and leaves produce a milky exudate. Leaf blades about 4.5-14 x 3-9 cm, petioles hairy, about 1.5-3.5 cm long. About 5-9 colleters (small dark glands) present on the upper surface of the midrib near its junction with the petiole. Upper and lower leaf blade surfaces clothed in pale brown hairs.

Inflorescence an umbelliform raceme. Peduncles about 25-30 mm long. Pedicels about 6 mm long. Sepals about 1-1.5 mm long. Corolla tube about 2 mm long, lobes recurved, about 1 mm long, hairy on the inner surface. Five elongated rib-like structures present on the inner surface of the corolla tube, alternating with the corolla lobes. Staminal corona not very well developed. Anthers sessile, fused together forming a single mass around the stigma. Anther connective extends beyond the anthers as a comparatively large translucent cowl. Pollen aggregated in pollinia.

Fruits slender, fusiform, about 50-80 x 6-7 mm. Seed features unknown.

Features not available.

Endemic to Australia, occurs in WA, NEQ, CEQ and southwards as far as north-eastern New South Wales. Altitudinal range in northern Australia from near sea level to 800 m. Grows in vine thicket and monsoon forest often on soils derived from basalt.

Gymnema pleiadenium F.Muell., Fragmenta Phytographiae Australiae 11: 77(1879), Type: In Australia orientali calidiore litorali, loco particulari nunc ignoto, nisi forsan Pine-River; W. Hill; F. Bailey. Gymnema dunnii (Maiden & Betche) P.I.Forst., Austrobaileya 2(3): 401(1984). Marsdenia rostrata var. dunnii Maiden & Betche, Proceedings of the Linnean Society of New South Wales 31(4): 736(1907), Type: Acacia Creek, Macpherson Range (Mrs. J.L. Dunew; December, 1905). Holo: NSW; iso: BRI.