Hoya enduensis Kiew 1989

Type description:

In The Malayan Nature Journal 42 (1989) 262-265.  R. Kiew. Hoya enduensis sp. nov. Hoya enduensis is presently known only from tributaries of the Ulu Endau, where it grows on trees on river banks. This new species adds to the growing list of endemics recorded from the Ulu Endau (Kiew et al., 1987), which is in the process of being gazetted as a state park.

            Foliis glabris ovatis-cordatis apicibus acutis 2 ad 2.5 cm longis et 2 ad 2.5 cm latis a congeneribus Peninsulae  Malaysiae divisa. Typus: R. Kiew RK2746 (UPM) Sg, Jasin, Jahore. Glabrous epiphyte climbing with a thin stem (1.5 mm thick in dried state (with internodes 6-9 cm long. Stem with climbing roots at the nodes and a more expansive root system developing below the leaves, Leaf ± sessile. Lamina ovate-cordate, humped with margines appressed to bark of supporting tree, 2.2 cm -2.5 by 2.5 cm, apex acute, in life succulent (not tough), plane above and venation obscure in life, 3 pairs of veins just visible in dried state, in life pale yellow-green above and below, upper surface sometimes spotted orange (by algae), margin not thickened.

            Inflorescence a pendant, axillary, sparsely-flowered corymb. Peduncle 23-45 mm long and 1 mm thick in dried state, distal part (2-7 mm long) covered by fruit scars, Pedicels very slender, 5-8 mm long. Flower buds pendant, 4 mm across, pale green suffused purple-red towards the base. Calyx pale green, glabrous, lobes oblong, 1 by 1 mm, apex rounded, pustulate on outer surface. Corolla glabrous on inner and outer surfaces, 4 mm across; lobes triangular, 2.5 by 2.5 mm. apex acute. Corona 3 mm across apex of upper lobes upturned and acute, lower lobes sloping down from and projected beyond upper lobes. Caudicles and pollinia broadly winged, 1 mm long. Ovary ovoid, 1 mm long. Fruit unknown.

            Ecology: It is an epiphytic climber growing in partial shade on trees on river banks at c. 75 m a.s.l. Distribution: Endemic to Ulu Endau, Jahor, Malaysia. Specimens examined: Jahore, Ulu Endau: Sg. Salat- 3 July 1985 R. Kiew s.n. (UMP). 2 June 19898 R. Kiew RK2746 (UPM). In vegetative characters it most resembles H. curtisii K & G., which is also a slender climber, but which has small (13 by 13 mm), orbicular leaves, which are apiculate. It also differs from H. curtisii in indumentum (H. curtisii is hirsute) and inflorescence characters  (Inflorescence of H. curtisii have peduncles to 5 mm longer are sessile); Kiew, 1987. In reproductive characters H. enduensis is most similar to H. lacunosa Bl. in its pendant, stalked inflorescence, in the shape of the corona, which has downward sloping lower lobes, and in the broadly winged caudicles (illustrated by Rintz, 1978). However H. enduensis is different in having glabrous corolla; that of H. lacunosa has inner surfaces covered by long, thick hairs. The leaves of H. lacunosa are also different. Usually they are longer than broad (2.5 - 3.5 by 1.5 - 2.5 cm) and have a thickened margine. In addition H. enduensis has smaller flowers (the corolla is  4 mm in diameter) than either H. curtisii (7mm) or H. lacunosa (8mm).

Translation: Leaves glabrous ovate-cordate apiculate acute 2 to 2.5 cm, long and 2 to 2.5 cm, wide , diverse from peninsula Malaysia cogenerics.

A photo of Hoya enduensis Kew foliage taken by Ted Green.