Dendrobium kontumense Gagnep.

Averyanov, Leonid V., Ponert, Jan, Nguyen, Phi Tam, Duy, Nong Van, Khang, Nguyen Sinh & Nguyen, Van Canh, 2016, A survey of Dendrobium Sw. sect. Formosae (Benth. & Hook. f.) Hook. f. in Cambodia, Laos and Vietnam, Adansonia 38 (2), pp. 199-217 : 206-208

6. Dendrobium kontumense Gagnep.

Bulletin de la Société botanique de France 79: 165 (1932). — Gagnep., Flore générale de l’Indo-Chine 6 (2): 239 (1933). — Sathap., T.Yukawa & Seelanan, Blumea 55: 77, fig. 2c-f (2010). — Aver., Turczaninowia 16 (4): 34, fig. 3H (2013). Dendrobium schildhaueri Ormerod & H.A.Pedersen, The Orchid

Review 111 (1254, Suppl.): 341 (2003). — Newman et al., A

Checklist for the Vascular Plants of Lao: 265 (2007). — Schuite-

man et al., Nordic Journal of Botany 26: 287 (2008).

Dendrobium virgineum auct. non Rchb.f.: Seidenf., Opera Botanica 83: 112, fig. 68, table 15b (1985); 114: 211, fig. 134 (1992). — Aver., Identification Guide to Vietnamese Orchids: 182 (1994). — P.H.Ho, An Illustrated Flora of Vietnam 3: 827, fig. 11061 (2000). — Aver. & Averyanova, Updated Checklist of the Orchids of Vietnam: 31 (2003). — Newman et al., A Checklist for the Vascular Plants of Lao: 266 (2007).

TYPUS. — S Vietnam. Annam: entre Giang Lo et Dak To, prov. de Kontum, forêt, 500 m alt., 8.IX.1930, Poilane 18280 (holo-, P [ P00408307 ]; iso-, C, P [ P00408308 ]) .

HABITAT, PHENOLOGY AND CONSERVATION STATUS. — Epiphyte on tall trees in primary and secondary evergreen and semideciduous, broad-leaved, mixed and coniferous closed and open forests and in pine woodlands on different kind of soils, particularly on steep rocky slopes and along tops of hills and mountains. [phone](1700) m. Fl. July-October. Not common. Expected IUCN Red List status – EN. DISTRIBUTION. — Laos (Borikhamxai, Khammouane, Vientiane), Vietnam (Dak Lak, Khanh Hoa, Kon Tum, Lam Dong, Thua Thien- Hue), Thailand .

MATERIAL EXAMINED. — Laos. Borikhamxai, Khamkeut, Dan Khum Ngan locality LA-VN 21a ( CPC Herbarium, LE, NHOL, NUOL); Khammouane, Napé, Poilane 4633 ( P [ P 00407646]); Vientiane, Phu Khao Khouai, A.D.Kerr 988 ( C); Vientiane, Kasi, Thong Mout, LA- VN 643 ( CPC Herbarium, LE, NHOL, NUOL).

Vietnam. Dak Lak, Buon Don , Krong Na, Yok Don, HLF 7167a, HLF 7347 ( HN, MO) ; Dak Lak, cultivé à Darlac , Vacherot s.n. ( P [ P00408303 ]) ; Dak Lak, Krong Bong , Cu Pui, VH 6292 ( HN, MO) ; Kon Tum, Dacuy , LX-VN 2222 ( HN, LE) ; Kon Tum, Gialai , L. Averyanov LX-VN s.n., anno 1985 ( LE photo) ; Kon Tum, Kon Plong, Hieu , Mang La, VH 5148 ( HN, LE), VH 5553 ( HN, LE, MO) ; Kon Tum, Mang Den , Konplong, LX-VN 2296 ( HN, LE) ; Kon Tum, Sa Thay , Chu Mom Ray, P. K. Loc et al., P-7991 ( LE) ; Lam Dong, Blao , Poilane 22202 ( P [ P00408306 ]) ; Lam Dong, Dalat, L. Averyanov s.n., HAL 8632 X.2005 ( HN, LE, LE photo, MO) ; Thu Thien-Hue, Nui Bach Ma , Hue, Poilane 27663, 29942 ( P [ P00408304 ]) ; Thua Thien- Hue , A Luoi, A Roang, HAL 7318 ( HN) ; Thua Thien-Hue, A Luoi, Hong Van, HAL 7631 ( HN) ; Thua Thien-Hue, Phu Loc, Bach Ma mt. , HLF 1303 ( HN, LE), HLF 1334 ( HN), HLF 1597 ( HN, MO) .

DESCRIPTION

Stems stout, erect, narrowly fusiform, 30-60 cm long, 1-1.5 cm in diameter, of many nodes. Leaves elliptic to narrowly ovate, 4-8(10) cm long, 1.5-3 cm wide. Inflorescences 1-3(5), each with (1)3-6 flowers. Pedicel and ovary 3-4 cm long. Flowers odorless, widely opening, 4-5 cm across, white, disc red. Sepals narrowly triangular ovate, acute, 2-2.5(3) cm long, 8- 1.2 cm wide. Petals obovate, narrowing to the base, round at apex, 2.5- 3 cm long, 1.5-1.8 cm wide, twice wider than sepals, strongly undulate along margin. Mentum narrowly conical to cylindrical, straight or slightly curved, 2-2.5 cm long, 3 mm in diameter.Lip pandurate, 3-lobed, 2.5-4 cm long, 1.5-2.5 cm wide; side lobes half circular, erect; median lobe broadly obovate, 1-1.5 cm long, 1.5-2.2 cm wide, emarginate, strongly undulate and slightly denticulate along margin; disc with 5 low insignificant rugose keels. Column white, 5-6 mm tall ( Figs 1I ; 2A ).

REMARKS

Lip coloration of D. kontumense is variable; its center bears small or large pink, reddish, bright red or orange-red blotch. For a long time Dendrobium kontumense has been identified in eastern Indochina by some authors as D. virgineum as proposed by Seidenfaden (1985). Meanwhile, true D. virgineum described from Myanmar (“from inexhaustible Birmah, Low, Herb. Reichenbach, 32503) distinctly differs from D. kontumense in its broad and short mentum ( Sathapattayanon et al. 2010). Dendrobium virgineum , a rare species does not occur in Cambodia, Laos and Vietnam.

Figures

FIG. 1. — A, B, Dendrobium bellatulum Rolfe; A, VH 2566; B, VH 2567; C, D, D. christyanum Rchb.f.; C, VH 950; D, CPC 6038; E, D. scabrilingue Lindl. (Konstantinov 29); F, G, D. suzukii T.Yukawa; F, Duy s.n., III.2014; G, L.Averyanov s.n., XI.2013); H, D. draconis Rchb.f. (HLF 7347); I, D. kontumense Gagnep.(LA-VN 21a). Photos: A-D, G-I, L. Averyanov; E, E. Konstantinov; F, N.V. Duy.

FIG. 2. — A, Dendrobium kontumense Gagnep.(L.Averyanov s.n., X.2005);B, D. roseiodorum Sathap.,T.Yukawa & Seelanan (L.Averyanov s.n., X.2005);C, D, D. daklakense Tich,Schuit. & J.J.Verm.; C, Vo Van Cong, s.n., XI.2015; D, V.Q.Binh & L.Averyanov, s.n., 7.XI.2014; E, D. infundibulum Lindl. (L.Averyanov s.n., Thailand, Chiangmai, 2002); F, G, D. wattii (Hook.f.) Rchb.f.; F, L.Averyanov s.n., XI.2013; G, HAL 8630; H, D. multilineatum Kerr (LA-VN 256). Photos: A-G, L. Averyanov; H, N. S. Khang.