Dissochaeta nodosa Korth. in Temminck, Verh. Nat. Gesch. Ned. Bezitt., Bot.: 239. 1844.

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

38. Dissochaeta nodosa Korth. in Temminck, Verh. Nat. Gesch. Ned. Bezitt., Bot.: 239. 1844. Map 21

Aplectrum nodosum (Korth.) Blume, Mus. Bot. 1(3): 37. 1849.

Anplectrum nodosum (Korth.) Triana, Trans. Linn. Soc. London 28: 84. 1872.

Dissochaeta montana Cogn. in A.DC. & C.DC., Monogr. Phan. 7: 558. 1891. Type: Indonesia. West Sumatra: Mt. Singgalang, 1700 m elev., O. Beccari PS 4124 (holotype: FI [FI007930, image seen]!).

Anplectrum yatesii Merr., Pap. Michigan Acad. Sci. 19: 175. 1934. Type: Indonesia. North Sumatra: Karoland, Berastagi, 12 Mar 1926, H.S. Yates 2012 (lectotype, designated here: BO [BO1429407]!; isolectotypes: L [L0537225]!, MICH [MICH-1111808, image seen]!, NY [NY00221311, image seen]!).

Dissochaeta yatesii (Merr.) Veldkamp, Blumea 24: 435, 443. 1979.

Type.

Indonesia. West Sumatra: Indrapoera, P.W. Korthals s.n. (lectotype, designated by Kartonegoro and Veldkamp 2010, pg. 143: L [L0537233]!; isolectotype: L [L0537232]!).

Description.

Branchlets terete, 4-5 mm in diameter, stellate-furfuraceous; nodes swollen, interpetiolar ridge present; internodes 5.5-7.3 cm long. Leaves: petioles flattened, 8-10 mm long, stellate-furfuraceous; blades ovate to elliptic, 8.3-12.5 × 3.5-6 cm, membranous, base subcordate, margin entire, apex acuminate, tip ca. 8-15 mm long; nervation with 1 pair of lateral nerves and 1 pair of intramarginal nerves; adaxially glabrous, abaxially glabrous to sparsely stellate-furfuraceous. Inflorescences terminal, up to 17 cm long, many-flowered; main axis angular, glabrescent to sparsely stellate-puberulous; primary axes up to 15 cm long with 5 or 6 nodes, secondary axes up to 4 cm long with 1 or 2 nodes, tertiary axes up to 1.5 cm long with 1 node; bracts and bracteoles inconspicuous, caducous; pedicels sparsely stellate-furfuraceous, 3-4 mm long in central flowers, 1-2 mm long in lateral flowers. Hypanthium broadly campanulate, ca. 4 × 3 mm, stellate-furfuraceous; calyx lobes truncate with 4 triangular tips, ca. 1 mm long, glabrous; petal buds conical, 2-3 mm long; mature petals obovate, 3-4 × ca. 3 mm, base clawed, apex rounded, glabrous. Stamens 8, equal or subequal, straight, filaments straight; alternipetalous stamens with filaments 4-6 mm long, anthers oblong or lanceolate, thecae ca. 5 mm long, pedoconnective ca. 0.5 mm long, basal crest triangular, ca. 1.5 mm long, acute, lateral appendages absent; oppositipetalous stamens with filaments ca. 3 mm long, anthers lanceolate, thecae 3-4 mm long, thick, basal crest ligular, 1-1.5 mm long, lateral appendages absent. Ovary ¾ of hypanthium in length, apex puberulous; style 8-10 mm long, curved at top, glabrous; stigma minute; extra-ovarial chambers 8, extending to the middle of the ovary. Fruits subglobose, 6-7 × 3-4 mm, glabrescent, apex mammiform; calyx lobes persistent, erect. Seeds ca. 0.5 mm long.

Distribution.

Sumatra.

Ecology and habitat.

Montane forest, in open places at 1300-1700 m elevation.

Specimens examined.

INDONESIA. North Sumatra: Karo, Brastagi, H.S. Yates 2012 (BO, L, MICH, NY). West Sumatra: Mount Singgalang, O. Beccari PS 4124 (FI); Indrapura, P.W. Korthals s.n. (L).

Figures

Map 21. Distribution of D. micrantha (■), D. nodosa (●) and D. papuana (▲).