Dissochaeta porphyrocarpa Ridl., Kew Bull. 1: 32. 1946.

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

41. Dissochaeta porphyrocarpa Ridl., Kew Bull. 1: 32. 1946. Fig. 23 , Map 23

Dissochaeta tawaensis Furtado, Gard. Bull. Singapore 20: 114. 1963. Type: Malaysia. Sabah: Elphinstone Province, Tawao, A.D.E. Elmer 21426 (holotype: SING!; isotypes: BM [BM000944477, BM001190928]!, BO [BO1429430]!, C [C10014565, image seen]!, K [K000859635]!, L [L0537282]!, P [P05283550, image seen]!, U [U0004011]!).

Dissochaeta rostrata Korth. var. porphyrocarpa (Ridl.) J.F.Maxwell, Gard. Bull. Singapore 33: 321. 1980.

Dissochaeta hirsuta auct. non Hook. f. ex Triana: Merr., Univ. Calif. Publ. Bot. 15: 224. 1929. p.p., excl. type.

Type.

Malaysia. Sarawak: Ulu Tawaran, 2000 ft., G.D. Haviland 1287 (lectotype, designated here: K [K000859633]!).

Description.

Climbing up to 6 m in height. Branchlets terete, ca. 3 mm in diameter, sparsely brown stellate-puberulous and densely covered with 1-2 mm long curved purplish-tip bristle hairs; nodes swollen, with an interpetiolar ridge; internodes 6.5-8 cm long. Leaves: petioles terete, 8-15 mm long, densely covered with stellate hairs and curved bristle hairs; blades ovate or elliptic, 9.7-12 × 4.7-7.8 cm, membranous, base subcordate, margin entire, apex acute; nervation with 1 pair of lateral nerves and 1 pair of intramarginal nerves; adaxially scabrid, with hairs and scattered curved bristle hairs, abaxially densely covered with curved bristle hairs in most parts, more densely so on midrib and margin. Inflorescences terminal, up to 24 cm long, many-flowered; main axis angular, densely covered with minute stellate hairs and curved purplish-tip bristle hairs; primary axes up to 12 cm long with 3 or 4 nodes, secondary axes 1.5-5 cm long with 1 or 2 nodes nodes, tertiary axes up to 1 cm long when developed with 1 node; bracts linear, 7-8 mm, covered with dense bristle hairs; bracteoles linear, ca. 4 mm long, covered with dense bristle hairs; pedicels densely stellate-furfuraceous and with curved purplish-tipped bristle hairs, 3-5 mm long in central flowers, 1-2 mm long in lateral flowers. Hypanthium campanulate, 5-6 × 3-4 mm, densely covered with brown stellate and curved purplish-tipped bristle hairs; calyx lobes truncate at base, slightly lanceolate, 3-4 mm long, densely bristly, glabrous inside; petal buds conical, 4-8 mm long, apex bristly; mature petals ovate-oblong, 5-6 × 3-5 mm, reflexed, apex obtuse, base clawed, glabrous, purple. Stamens 8, unequal, filaments curved sideways, light green; alternipetalous stamens with ca. 7 mm long filaments, anthers lanceolate, sickle-shaped, thecae 9-10 mm long, apex rostrate, purple, pedoconnective ca. 2 mm long, basal crests minute, triangular or ligular, 1-2 mm long, lateral appendages paired, filiform, 4-5 mm long, white; oppositipetalous stamens with ca. 6 mm long filament, anthers thick, S-shaped, thecae 8-9 mm long, purple, basal crests minute, spur-like, erect, ca. 0.5 mm long, lateral appendages paired, filiform, 1-2 mm long, white. Ovary ⅔ of hypanthium in length, apex villous; style 8-10 mm long, curved at end, glabrous, light green; stigma minute, capitate; extra-ovarial chambers 8, extending to the middle of the ovary. Fruits urceolate, 8-10 × 6-8 mm, densely covered with curved purplish-tip bristle hairs; calyx lobe remnants persistent, reflexed. Seeds ca. 0.5 mm long.

Distribution.

Borneo.

Ecology and habitat.

Primary mixed Dipterocarp forest or low montane forest on river banks or in open places at 180-900 m elevation.

Vernacular name.

Bang derd (Kenyah).

Note.

The bristles in D. porphyrocarpa are distinct as they are eglandular, short and curved; they resemble those of D. rostrata . However, bracteoles in D. porphyrocarpa are caducous while persistent and conspicuous in D. rostrata .

Specimens examined.

MALAYSIA. Sabah: Keningau, Crocker Range, 15 Aug 1978, Nordin Abas SAN 85957 (K, L); Ibid., Witti Range Area, Ulu Sg. Mantuluk, 17 Jan 1986, Asik Mantor SAN 113279 (K); Nabawan, 12 Nov 1973, Dewol & Abdul Karim SAN 77955 (K, L); Kalabakan, Ulu Segama, 16 Dec 1982, Fidilis SAN 95585 (L); Lahad Datu, Danum Valley, 238 m, 6 Jul 2006, E. Rosalia et al. SAN 145988 (K, L); Ibid., Ulu Segama, 16 Jul 1970, P.F. Cockburn SAN 70925 (K, L); Nabawan, Ulu Sungai Nabawan, 21 Feb 1990, Asik Mantor SAN 128382 (L); Pandewan, Mesopo River, 10 Mar 1986, Sumbing & Asik SAN 114076 (K, L); Pinangah, Imbak River, 200 m, 1 Jul 2000, W.J.J.O. de Wilde, M. Tajudin & M. Postar SAN 143959 (K); Ranau, Ulu Sg. Bidon, 19 Jul 1985, Amin & Ismail SAN 110449 (K, L); Ibid., Mt. Kinabalu, Gurulau Spur, 8 Nov 1915, M.S. Clemens 10789 (PNH); Ibid., Mt. Kinabalu, Gurulau Spur, 27 Nov 1915, M.S. Clemens 10824 (PNH); Ibid., Mt. Kinabalu, Dallas, 914 m, 7 Aug 1931, J. Clemens & M.S. Clemens 30359 (K, L); Ibid., 11 Aug 1931, J. Clemens & M.S. Clemens 26058A (BO); Ibid., 31 Oct 1931, J. Clemens & M.S. Clemens 26028 (BM, BO, K, L); Ibid., Nov 1931, J. Clemens & M.S. Clemens 30357 (BO, K, L); Ibid., Ulu Tungud, 343 m, 27 Jul 2005, L.G. Saw et al. SAN 146068 (L); Tawau, Oct 1922-Mar 1923, A.D.E. Elmer 21426 (BM, BO, C, K, L, P, SING, U). Sarawak: Ulu Tawaran, 600 m, G.D. Haviland 1287 (K); Tampassuk, near Kiau, 1066 m, G.D. Haviland 1288 (K); Baram, Ulu Tinjar, Dulit Range, 365 m, 11 Aug 1974, P.K. Chai S.34771 (K, L); Balleh, Mujong, N Semperaja, 200 m, 17 Apr 1964, Othman bin Haron S.19873 (K, L); Belaga, Sungai Semawat, 250 m, 19 Oct 1981, C. Hansen 705 (L); Bintulu, Lumut Range, Ulu Sg. Gelang Bata, 250 m, 19 Sep 1992, Abang Mochtar & P.C. Yii S.65799 (K, L); Ibid., Tubau, Bukit Sekiwa, 180 m, 4 Sep 1986, Abang Mochtar S.53996 (L); Kapit, Batang Balui, Sungai Jitang, 300 m, 28 Feb 1992, Othman et al. S.62032 (L); Marudi, Pulong Tau National Park, Ulu Sungai Baong, 9 May 2007, J. Sang et al. S.98016 (K); Miri, Lambir National Park, 27 Sep 1978, R. George S.40438 (K); Ibid., Gunung Mulu, Melinau Crossing, 200 m, 5 May 1978, G. Argent & B. Coppins 1160 (BM); Padawan, Kampung Braang Wah, 300 m, 8 May 1975, James et al. S.37410 (K, L); Ibid., Bukit Woen, 350 m, 2 Oct 1987, P.C. Yii S.61445 (K, L). BRUNEI. Belait: Labi, Mendaram Valley, 20 m, 23 Oct 1989, L.L. Forman & J.B.J. Blewett 1034 (K, L); Ibid., 18 Mar 1991, M.J.S. Sands & R.J. Johns 5445 (K, L); Ibid., Wong Kadir, 150 m, 19 Mar 1993, M.J.E. Coode et al. 7227 (K, L). Temburong: Kuala Belalong, Batu Apoi, 17 Nov 1991, C. Hansen 1579 (K, L); Temburong River Valley, 50 m, 27 Apr 1992, R.J. Johns et al. 7389 (K, L). INDONESIA. East Kalimantan: West Kutai, River Kiauw, 700 m, 27 Oct 1925, F.H. Endert 4660 (BO, L); Ibid., Long Ibut, 150 m, 10 Nov 1925, F.H. Endert 4754 (BO).

Figures

Figure 23. Dissochaeta porphyrocarpa a habit b branchlet c hypanthium d alternipetalous stamen e oppositipetalous stamen f fruit. Photographs by D. Penneys; voucher: Penneys 2486 (WNC).

Map 23. Distribution of D. porphyrocarpa (●) and D. punctulata (■).