Dissochaeta malayana Furtado, Gard. Bull. Singapore 20: 110. 1963.

Kartonegoro, Abdulrokhman, Veldkamp, Jan Frits, Hovenkamp, Peter & Welzen, Peter van, 2018, A revision of Dissochaeta (Melastomataceae, Dissochaeteae), PhytoKeys 107, pp. 1-178 : 1

34. Dissochaeta malayana Furtado, Gard. Bull. Singapore 20: 110. 1963. Map 20

Dissochaeta rostrata Korth. var. malayana (Furtado) J.F.Maxwell, Gard. Bull. Singapore 33: 320. 1980.

Type.

Malaysia. Terengganu: Kemaman, Bukit Kajang 350 m, E.J.H. Corner SFN 30381 (holotype: SING!).

Description.

Branchlets terete, 2-3 mm in diameter, covered with scattered, ca. 1 mm long, dark purple bristle hairs; nodes swollen, with interpetiolar ridge, densely covered with brown stellate-furfuraceous hairs and scattered bristles; internodes 4.5-7 cm long. Leaves: petioles terete, 5-8 mm long, densely covered with stellate-furfuraceous and bristle hairs; blades ovate, 7.5-10 × 3.5-4.8 cm, membranous, base emarginate, margin entire, apex acuminate, tip ca. 0.5 cm long; nervation with 1 pair of lateral nerves and 1 pair of intramarginal nerves; surfaces hirsute, with sparse stellate hairs and scattered dark bristle hairs, more densely so at midrib and margin. Inflorescences terminal, up to 15 cm long, many-flowered; main axis angular, covered with scattered, dark purple bristle hairs; primary axes up to 12 cm long with 3-5 nodes, secondary axes 2-5 cm long with 1 or 2 nodes, tertiary axes up to 1.5 cm long with 1 node; bracts linear, 3-4 mm long, with stellate-furfuraceous and dark purple bristle hairs; bracteoles linear or subulate, 1-2 mm long, with stellate-furfuraceous and dark bristle hairs; pedicels with densely stellate-furfuraceous and dark purple capitate bristle hairs, 5-6 mm long in central flowers, 2-3 mm long in lateral flowers. Hypanthium suburceolate, 8-10 × 3-4 mm, densely covered with stellate-furfuraceous and dark capitate purple bristle hairs; calyx lobes truncate with undulate tip, 1-1.5 mm long; petal buds conical or rounded, 4-5 mm long, apex bristly; mature petals obovate, ca. 7 × 4 mm, not-reflexed, base clawed, apex rouded, bristly, otherwise glabrous, pink-purple. Stamens 8, subequal, filaments curved sideways, yellow; alternipetalous stamens with 7-8 mm long filaments, anthers lanceolate, sickle-shaped, thecae ca. 10 mm long, apex rostrate, yellow, pedoconnective 1-1.5 mm long, basal crests minute, triangular, ca. 0.5 mm long, lateral appendages paired, filiform, 3-4 mm long; oppositipetalous stamens with 7-8 mm filaments, anthers thick, slightly S-shaped, thecae 9-10 mm long, pink, basal crests minute, ligular or spur-like, ca. 0.5 mm long, lateral appendages paired, filiform, 1-1.5 mm. Ovary ⅔ of hypanthium in length, apex villous and bristly; style 13-15 mm long, curved at end, glabrous, pink; stigma minute, capitate; extra-ovarial chambers 8, extending to the middle of the ovary. Fruits urceolate, 8-10 × 4.5-5 mm, sparsely stellate-furfuraceous and densely covered with dark capitate bristle hairs; calyx lobe remnants persistent, reflexed. Seeds ca. 0.5 mm long.

Distribution.

Peninsular Malaysia (Terengganu).

Ecology and habitat.

Lowland forest at 150-400 m elevation.

Note.

This species resembles D. johorensis ; both species have most parts covered by bristle hairs. Dissochaeta malayana is different in having more distinct dark purple bristle hairs and truncate calyx lobes and geographically it is disjunct, only present in the northern part of the peninsula.

Specimens examined.

MALAYSIA. Terengganu: Ulu Brang, 365 m, Jul 1937, L. Moysey & Kiah SFN 33858 (BO, K); Kemaman, Bukit Kajang, E.J.H. Corner SFN 30381 (SING); Dungun, Jerangau Road, 16 Nov 1954, J. Sinclair & Kiah SFN 40492 (BM, BO, K, L).

Figures

Map 20. Distribution of D. malayana (●), D. marumioides (■) and D. maxwellii (▲).