Original illustration by Blume (from Rumphia, vol. 4, pl. 185)
Hoya macrophylla is a species of plant in the genusHoya of the subfamily Asclepiadoideae
Hoya macrophylla is an epiphytic, climbing and twining plant with shoots that are round in cross-section. The leaves are stalked, the thick, glabrous petioles are up to 2.5 cm long. The fleshy to leathery leaf blades are ovate or ovate-oblong, and 14 to 25 cm long and 4.5 to 11 cm wide. The apex is acute to long-pointed, and the base is acute, rarely almost round-blunt. They are dark green above, somewhat reddish below. The lighter leaf veins are clearly visible. It consists of the midrib and a pair of leaf veins running margin-parallel about midway between midrib and leaf margin. Midrib and lateral ribs as well as the leaf margins are connected by transverse leaf veins.
The pedunculate, more or less spherical inflorescence contains about 24 to 30 flowers. Up to five inflorescences can arise from one growth node. The inflorescence stem is 6 to 10 cm long, more or less purple in colour and glabrous. The purple inflorescence pedicels are 1 to 3 cm long and sparsely hairy or glabrous. The sepals are triangular and about 0.6 cm long. They are red and very sparsely hairy on the outside. The corolla is pale pink to purple. The fleshy corolla tips are ovate, pointed and recurved. They are glabrous on the outside, densely covered with whitish papillae on the inside. The secondary corolla is whitish to pink, correspondingly darker in the middle (to dark pink). It has a diameter of 3.5 mm. The staminal cusps of the secondary crown are keeled on the upper side. The outer process is acute and ascending, the inner process is pointed. The pollinia are linear-lanceolate.
Geographical distribution and habitat
- Christiane Hoffmann, Ruurd van Donkelaar, Focke Albers: Hoya. In: Focke Albers, Ulli Meve (Eds.): Sukkulenten-Lexikon Band 3 Asclepiadaceae (Silk plant family). S. 147-160, Ulmer, Stuttgart 2002, ISBN 3-8001-3982-0 (p. 155).
- Robert Dale Kloppenburg, Ann Wayman: The World of Hoyas – a pictorial guide. A revised version. 248 p., Orca Publishing Company, Central Point, Oregon, 2007 ISBN 0-9630489-4-5 (p. 158/59)
- Surisa Somadee, Jens Kühne: Hoya 200 different wax flowers. 96 p., Formosa-Verlag, Witten 2011 ISBN 978-3-934733-08-4 (p. 61)
- Carl Ludwig von Blume: Rumphia, sive Commentationes Botanicae imprimis de plantis Indiae Orientalis, tum penitus incognitis tum quae in libris Rheedi, Rumphii, Roxburghii, Wallichii, aliorum recensentur. Tomus Quartus. Amsterdam, 1858 pp. 32, pl. 185 (Online at Biodiversity Heritage Library)
- Kew Sciences – Plant of the World online: Hoya macrophylla flower
- Yves Laumonier: The Vegetation and Physiography of Sumatra. Klüwer Academic Publishers, 1997 (Geobotany, Vol. 22) ISBN 978-94-010-6502-3
- Carl Georg Blume: Bijdragen tot de Flora van Nederlandsch Indië, 16. Stück, p. 1063, Ter Lands Drukkerij, Batavia/Djakarta, 1827 Online at Biodiversity Heritage Library.