Dissochaeta macrosepala Stapf, J. Linn. Soc., Bot. 42: 80. 1914.

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

33. Dissochaeta macrosepala Stapf, J. Linn. Soc., Bot. 42: 80. 1914. Fig. 21 , Map 18

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

Type.

Malaysia. Sabah: Ranau, Mt. Kinabalu, Ridge above Bundu Tuhan, 3000 ft. elev., Feb 1910, L.S. Gibbs 3951 (holotype: K [K000859636]!).

Description.

Climbing up to 3 m in height. Branchlets terete, 3-4 mm in diameter, densely covered with brown stellate-tomentose hairs, glabrescent; nodes swollen, with interpetiolar ridge; internodes 4.4-5.5 cm long. Leaves: petioles terete, 5-8 mm long, densely brown stellate-tomentose; blades ovate, 6-6.2 × 4-4.3 cm, subcoriaceous, base cordate, margin entire, apex acuminate, tip ca. 0.5 cm long; nervation with 1 or 2 pairs of lateral nerves and 1 pair of intramarginal nerves; adaxially glabrous, with prominent reticulate sunken venation, abaxially densely covered with brown stellate-tomentose hairs. Inflorescences terminal, up to 15 cm long, many-flowered; main axis densely covered with brown stellate-tomentose hairs; primary axes up to 12 cm long with 3 or 4 nodes, secondary axes 2-2.5 cm long with 1-3 nodes, tertiary axes up to 1 cm long with 1 node; bracts linear or leaf-like, 4-15 mm long, stellate-tomentose, caducous; bracteoles subulate, 2-6 mm long, stellate-tomentose, caducous; pedicels brown stellate-tomentose, 3-4 mm long in central flowers, 1-2 mm long in lateral flowers. Hypanthium tubular to suburceolate, 5-6 × 2-3 mm, densely brown stellate-tomentose; calyx lobes lanceolate, 4-4.5 mm long, apex acute, tomentose; petal buds conical, 4-5 mm long, glabrous; mature petals ovate, 6-8 × 4-5 mm, base clawed, apex acute, bright pink. Stamens 8, subequal, filaments curved sideways, yellowish; alternipetalous stamens with 6-7 mm long filaments, anthers slender, lanceolate, sickle-shaped, thecae 8-9 mm long, purplish, pedoconnective 2-3 mm long, basal crest triangular 1-2 mm long, whitish, lateral appendages prolonged from base of crest, paired, filiform, 4-5 mm long, whitish; oppositipetalous stamens with 5-6 mm long filaments, anthers thicker, S-shaped, thecae 6-7 mm long, purplish, basal crest minute or spur-like, whitish, lateral appendages from base with a paired, ligulate appendages, ca. 1 mm long, whitish. Ovary ⅔ of hypanthium in length, apex pubescent; style 10-12 mm long, curved at the apex, glabrous, white with purplish apex; stigma minute, capitate, yellowish; extra-ovarial chambers 8, extending nearly to the middle of the ovary. Fruits ovoid or urceolate, 8-9 × 5-6 mm long, densely covered with stellate-tomentose hairs; calyx lobes persistent, reflexed. Seeds ca. 0.5 mm long.

Distribution.

Borneo (Mount Kinabalu).

Ecology and habitat.

Lower montane forest, in open places, at ca. 914 m elevation.

Note.

The indumentum of D. macrosepala resembles D. densiflora , but the former species is different in the long, lanceolate calyx lobes. Maxwell (1980b) considered both species as varieties of D. rostrata . Stapf and Green (1914) incorrectly noted that the species has four stamens, but it has 8 stamens like the other similar species.

Specimens examined.

MALAYSIA. Sabah: Ranau, Mt. Kinabalu, Bundu Tuhan, 914 m, Feb 1910, L.S. Gibbs 3951 (K); Ibid., Dallas, 914 m, 1 Dec 1931, J. Clemens & M.S. Clemens 30340 (L).

Figures

Map 18. Distribution of D. inappendiculata (●), D. laevis (■) and D. macrosepala (▲).

Figure 21. Dissochaeta macrosepala a habit b branchlet c hypanthium d flower Photographs by D. Penneys; voucher: Penneys 2512 (WNC)].