Dendrobium tuensangense N.Odyuo & C.Deori, 2017

Odyuo, Nripemo, Deori, Chaya & Daimary, Ranjit, 2017, Dendrobium tuensangense, a new species of Orchidaceae from Nagaland, Northeast India, Phytotaxa 311 (2), pp. 185-189 : 185-188

publication ID	https://doi.org/ 10.11646/phytotaxa.311.2.6
persistent identifier	https://treatment.plazi.org/id/DA511C6C-3405-5557-FF01-F7AFFAA9598A
treatment provided by	Felipe
scientific name	Dendrobium tuensangense N.Odyuo & C.Deori
status	sp. nov.

Treatment

Dendrobium tuensangense N.Odyuo & C.Deori View in CoL sp.nov. ( Fig. 1 View FIGURE1 and 2A–J View FIGURE 2 )

Dendrobium tuensangense is similar to D. dantaniense and D. bicameratum due to its habit, lateral or sub terminal capitate raceme inflorescence, three lobed lip but differs in having uniformly elongate, slender, stems, floral bracts ovate to elliptic acuminate, obtuse shorter than the ovary and pedicel; sepals and petals pale cream coloured, sometimes speckled with light purple in petals; side lobes papillose on dorsal and ventral side, papillae purplish, fan shaped, very broad, apex obtuse, margin erose; midlobe apex narrower, 1 mm broad; anther head with an acute projection of 0.5 mm long. It is also similar to Dendrobium bicameratum Lindl. but differs in having uniformly elongate, slender, stems, floral bracts ovate to elliptic acuminate, shorter than the ovary and pedicel, an acute projection of 0.5 mm long on the anther head; side lobes papilose on dorsal and ventral side, papillae purplish, fan shaped, very broad, obtuse, margin erose.

Type: — NDIA: Nagaland, Tuensang district, Bakhong forest reserve, Chingmei village , 3.06.2016, N. Odyuo 132814 (holotype ASSAM!; isotype CAL!) .

Habit suberect epiphytic, viviparous herbs. Roots 1–1.5 mm thick, in the middle, slender, filiform, branched. Stems 35–45 cm long, uniformly slender, sheathed, leafy, noded and shoots coming out from nodes, 3.5–5 mm in dm. Leaves 2.5–6.8 × 0.4–0.9 cm, more towards apex, lanceolate, obliquely notched, acute at apex, entire, nerved, sheathed. Inflorescences axillary, sub-terminal, capitate raceme, 3-4-flowered in a cluster arising from short peduncles on nodes of defoliate stems; peduncles 5–5.5 mm long, sheathed; sheaths 3–4 numbers; floral bracts 3.6 × 2 mm, ovate to elliptic acuminate, obtuse, greenish white speckled with purple along the 3 veins and towards apex; ovary and pedicel 4 × 1.1 mm, greenish, longer than the floral bracts, ovary straight, ridged. Flowers 8–10 × 10–11.5 mm, sepals and petals, thin textured, pale creamy, sometimes speckled with light purple in petals, lip whitish, midlobe yellowish, side lobes dorsal and ventral side papillose, papillae purplish. Sepals ovate obtuse. Dorsal sepal 5.9–6.5 × 3.5–4.5 mm, base narrow, 5-nerved; laterals 5.5 × 4.5 mm, broad at base (5.5 mm), 4–5 veined. Petals 5.5–6 × 2.5–3.2 mm, broadly lanceolate, subacute to obtuse, 5-veined, laterals branched. Lip 4–5.5 mm long, three lobed, 6 prominent veins, branched towards side lobes; side lobes 4–5 mm broad, papillose on dorsal and ventral side, papillae purplish, fan shaped, apex obtuse, margin erose; midlobe narrow, short, swollen, apex 1 mm broad, yellowish, margin erose; disc thick, two short wavy keeled rows running from the centre towards the apex of midlobe. Column and foot 4.5–5 × 2.2 mm, whitish with purple lining around the stigmatic cavity; foot parted into two halves; stelidia 2, whitish, obtuse; rostellum wide, rectangular, whitish.Anther 1.9–2 × 1.2 mm, rounded, head with an acute projection of 0.5 mm long, whitish, glabrous, operculum slightly erose. Pollinia 0.7 × 0.2 mm, in 2 pairs, sub equal, yellow.

Phenology: —Flowering: June; Fruiting not seen.

Distribution and habitat:— Dendrobium tuensangense was found growing epiphytically on moss-covered branches of trees. The species was flourishing in a steep subtropical hill forest along a stream side at 2000 m altitude near Bakhong forest reserve, Chingmei village, Tuensang district of Nagaland, Northeast India . It was associated with other orchid species in the genera Dendrobium Sw. , Pholidota and Coelogyne amongst others.

Etymology: The specific epithet is given in honour of the district Tuensang of Nagaland, India .

Conservation status:— Data Deficient (DD). Dendrobium tuensangense is so far known only from a single locality in the Tuensang district of Nagaland and further exploration is necessary before a threat status can be given.

ridged, covered with persistent sheaths,

20–45 cm long. Leaves oblong-elliptic, obliquely notched, acute Leaves ovate-elliptic, or lanceolate, Leaves linear lanceolate, obliquely at apex. obliquely notched and sub obtuse at notched, acute at apex.

apex. Floral bracts, ovate, sub acuminate, greyish white, Floral bracts elliptic, sub acute to Floral bracts ovate to elliptic acuminate, speckled with purple, 3-prominent veins, shorter obtuse, concave, greyish white, obtuse, greenish white, speckled with than or equalling the ovary and pedicel. speckled with greenish and purple, purple along the 3-veins and towards

5-nerved, longer than the ovary and apex, shorter than the ovary and pedicel.

pedicel.

Sepals and petals dirty yellow with stripes of red Sepals and petals yellow or light Sepals and petals light cream sometimes speckles. orange speckled with maroon to red speckled with light purple in petals. dots along the veins. Lip 3-lobed, golden yellow, 5 veined, laterals Lip 3 lobed, yellowish or light Lip 3 lobed, whitish, 6 prominent branched; side lobes narrow, red, triangular, acute, orange, 5 veined, laterals branched; veined, branched towards side lobes; margin not erose; midlobe apex long and broad, sidelobes broad, red, obtuse, margin side lobes very broad, fan shaped, yellowish; disc surface thickened. not erose; midlobe apex short papilose, margin erose; midlobe, short and broad,yellowish; disc surface and narrow; disc thick, two short wavy thickened. keeled rows running from the centre towards the apex of mid lobe. Anther whitish, rounded, without acute projection. Anther whitish, rounded without acute Anther whitish, rounded with acute projection. projection of 0.5 mm long.