Tag:

Montane (1500-2500 m)

Orchideaceae

Dendrobium fuscescens

by GP Jürgens

Griff.

Bhutan2015 449
  Bhutan Jakar 2500m, October
Bhutan2015 450
  Bhutan Jakar 2500m, October
Bhutan2015 451
  Bhutan Jakar 2500m, October
Bhutan2012 1129
Bhutan Koma-Chu-Valley 950m, October
Bhutan2012 1131
Bhutan Koma-Chu-Valley 950m, October
Bhutan2012 1358
Bhutan Sandrup 1500m, October

Description

Dendrobium fuscescens Griff. is an epiphytic orchid of the eastern Himalaya and adjacent Indo-Burmese region, recorded by GBIF from China, India, Myanmar, Nepal and Bhutan across some 69 occurrences. It grows on the trunks and branches of trees in humid broad-leaved and mixed forests, ranging over a broad altitudinal span as shown by the Bhutanese records at Jakar around 2500 m, in the Koma-Chu valley near 950 m, and at Sandrup about 1500 m, all in October. This spread from warm temperate valleys to cooler montane forest reflects a tolerance of moist, shaded, mossy bark substrates with good air movement.

The plant produces clustered, slender, elongate cane-like pseudobulbous stems that are somewhat flattened and grooved, becoming yellowish with age. The thin-textured, lanceolate to oblong leaves are distichously arranged along the stems and are usually deciduous in the dry season, leaving the canes bare. Short lateral racemes of a few small flowers arise from nodes on the older leafless stems; the flowers are pale, often tinged greenish or brownish-yellow (the epithet fuscescens alluding to the darkening tint), with spreading lanceolate sepals and petals and a labellum bearing a hairy or papillose disc and recurved lateral lobes, the lateral sepals forming a short mentum at the column foot.

Dendrobium is one of the largest orchid genera, and D. fuscescens belongs among the slender deciduous-caned Himalayan species. It is poorly documented, with few georeferenced records, and like most epiphytic orchids it is sensitive to deforestation and collection. No formal assessment singles it out as threatened, but its dependence on intact forest canopy makes habitat protection important, and all Dendrobium are listed on CITES Appendix II.

Author: Griff. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, World Checklist of Dendrobium, Seidenfaden monograph of Orchids of Indochina

Orchideaceae

Dendrobium heterocarpum

by GP Jürgens

Wall. ex Lindl.

Nepal1992 94 P130 ergebnis
Nepal Amjilassa 2300m March 
Nepal1992 162 P239 2 ergebnis
Nepal Amjilassa 2300m March 
Nepal1992 163 P244 ergebnis
Nepal Amjilassa 2300m March 

Description

Dendrobium heterocarpum is a widespread epiphytic orchid of the tropical and subtropical forests of southern and southeastern Asia. GBIF data document its broad native range across the Philippines, Thailand, India, Nepal, Vietnam, China, Indonesia, Bhutan, Sri Lanka and Myanmar, with additional records from cultivation in the United States, Britain, Belgium and Germany, totalling around 261 occurrences. It grows as an epiphyte on the trunks and larger branches of trees in seasonally dry, well-lit montane and submontane forest, often in regions with a marked dry season that triggers flowering. The photographed plant from Amjilassa in eastern Nepal at 2300 m, flowering in March, illustrates its occurrence in the mid-elevation hill forests of the central Himalaya, where spring blooming follows the cool dry winter.

It is a sympodial epiphyte with clustered, erect to pendent, cane-like pseudobulbs that are somewhat fusiform and longitudinally furrowed when old, bearing several lanceolate, deciduous leaves along their length. The flowers, borne in small lateral clusters from nodes of leafless canes, are fragrant, with cream to pale yellow, often reflexed sepals and petals; the labellum is broad and recurved, golden-yellow with reddish-brown longitudinal veining and a pubescent disc. The fruit is a ribbed, ellipsoid capsule releasing dust-like seeds.

Dendrobium is among the largest orchid genera, and D. heterocarpum belongs to section Dendrobium, characterised by deciduous-leaved, nodally flowering canes. Long valued in horticulture for its sweetly scented, durable flowers, the species is collected from the wild across parts of its range, and like most epiphytic orchids it is listed under CITES Appendix II to regulate international trade. Its pollination depends on deceptive attraction of bees to the showy, nectarless labellum.

Author: Wall. ex Lindl. · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of China (Orchidaceae), The Genus Dendrobium (Lavarack, Harris & Stocker)

Orchideaceae

Dendrobium hookerianum

by GP Jürgens

Lindl.

Bhutan2012 439
Bhutan Wangdi 2500m, September
Bhutan2012 1256
Bhutan Trashigang 2000m, October
Bhutan2012 1257
Bhutan Trashigang 2000m, October

Description

Dendrobium hookerianum, Hooker's dendrobium, is an eastern Himalayan epiphytic orchid known from China, India, Bhutan, Myanmar and Nepal, with 127 GBIF occurrences concentrated in the moist mid-montane forests of the region. It grows on tree trunks and branches in humid temperate broadleaved and conifer forest, broadly between about 1500 and 2500 m. The illustrated plants were recorded in Bhutan at Wangdi (Wangdue) at 2500 m in September and at Trashigang at 2000 m in October, autumn-flowering populations in mist-laden forest where cool nights and high humidity prevail.

The species forms long, pendent or arching, slender stems clothed in tubular sheaths and bearing many distichous, lanceolate, thin-textured leaves. From the upper nodes arise lateral racemes carrying several large, golden-yellow flowers. The spreading, elliptic sepals and broader petals are clear yellow, and the broad, suborbicular, fringed labellum is conspicuously marked with two deep maroon to blackish blotches on the disc and edged with a dense marginal fringe. The mentum is short, the column with a prominent foot, and the pollinia waxy.

Named in honour of Sir Joseph Dalton Hooker, the species belongs to Dendrobium section Dendrobium and is prized among Himalayan orchids for its showy fringed lip. Its restricted eastern Himalayan range, autumn flowering and ornamental appeal make it a target for collectors, and combined with ongoing forest clearance this renders wild populations vulnerable. International trade in the genus is regulated under CITES Appendix II.

Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Orchids of Bhutan, Dendrobium and its Relatives (Lavarack et al.)

Orchideaceae

Dendrobium jenkinsii

by GP Jürgens

Wall. ex Lindl.

Bhutan2014 716
Bhutan Wangdi Phodrang 2280m, June
Bh2008 454 P712
Bhutan Tsang-Chu, 1520m April

Description

Dendrobium jenkinsii is a small epiphytic orchid distributed across the Eastern Himalaya, southern China and mainland Southeast Asia, with GBIF occurrences from China, Bhutan, India, Vietnam, Myanmar, Laos and Thailand among others. It grows as an epiphyte on tree trunks and large branches in open, well-lit montane and submontane forest, often on exposed boughs where it endures a marked seasonal alternation of monsoon moisture and a dry, cool resting period. It occurs at low to middle elevations; the Bhutanese records from Wangdue Phodrang at about 2280 m in June and from the Tsang-Chu valley at 1520 m in April bracket its altitudinal range and indicate spring to early-summer flowering.

The species forms small, clustered, ovoid to discoid pseudobulbs pressed against the substrate, each compressed, wrinkled when mature and bearing a single leathery apical leaf. The inflorescence is short and few-flowered, arising near the pseudobulb apex. The flowers are comparatively large for the plant's size and bright golden-yellow, with spreading, broadly elliptic sepals and petals. The labellum is the showiest part, broad, orbicular-reniform and conspicuously fringed or fimbriate at the margin, with a densely hairy or velvety disc; the short column bears a foot forming a mentum with the lateral sepals. The fruit is a small capsule.

D. jenkinsii belongs to Dendrobium section Densiflora and is closely allied to the larger D. lindleyi (D. aggregatum), from which it differs chiefly in its solitary or few-flowered inflorescences and smaller stature; the two have at times been confused or treated as conspecific. The species is much sought in horticulture, and wild collection compounds the pressures of forest loss across its range, making it a taxon of potential conservation concern despite a wide overall distribution.

Author: Wall. ex Lindl. · Sources: POWO (Kew), GBIF, Flora of China, The Orchids of Bhutan (Pearce & Cribb), Dendrobium and its Allies (Lavarack et al.)

Orchideaceae

Dendrobium longicornu

by GP Jürgens

Lindl.

Bhutan2015 453
Bhutan Trontsa 2300m, October
Bhutan2012 441
Bhutan Wangdi 2600m, September
Bhutan2012 1331
Bhutan Pemagatse 2600m, September

Description

Dendrobium longicornu is an epiphytic orchid widespread across the eastern Himalaya and Indo-Burmese region, with GBIF recording over 300 occurrences and native range spanning India, China, Nepal, Bhutan, Vietnam, Myanmar, Bangladesh and Thailand, besides cultivated records in Europe. It grows as an epiphyte on mossy trunks and branches in humid, temperate to subtropical broad-leaved forest, typically between about 1500 and 2700 m. Bhutanese material was photographed at Trontsa (2300 m), Wangdi and Pemagatse (both 2600 m) in September and October, flowering on shaded, moss-laden trees in cool montane woodland.

The plant forms tufted, slender, erect to pendulous stems clothed in black-hairy leaf sheaths, bearing thin, lanceolate leaves toward the apex. The flowers, borne singly or few together near the stem tips, are showy and predominantly white with a fringed labellum marked by orange to greenish veining in the throat. The narrow tepals are spreading; the diagnostic feature is the long, slender, horn-like spur (mentum) formed by the lateral sepals and column foot, from which the epithet "longicornu" derives. The column is short, the anther cap bearing waxy pollinia, and the fruit a ribbed capsule.

Within the large genus Dendrobium, this species belongs to the white-flowered Formosae (nigrohirsute) section, distinguished by the dark hairs on stems and sheaths. Although widespread, it is sought by orchid collectors and is affected by habitat loss and overharvesting; like all Dendrobium it is listed on CITES Appendix II, regulating international trade.

Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Orchids of Bhutan (Pearce & Cribb), CITES Appendix II listing

Orchideaceae

Dendrobium moniliforme

by GP Jürgens

(L.) Sw.

Bhutan2014 808
Bhutan Mo-Chu 1880m, June
Bhutan2014 809
Bhutan Mo-Chu 1880m, June
Sikkim2011 173
Sikkim Lachung 2660m, June

Description

Dendrobium moniliforme is one of the most widely distributed temperate dendrobiums, ranging from Japan, Korea, Taiwan and China westward through the Himalaya to Nepal, with GBIF documenting over a thousand occurrences across this broad East Asian and Himalayan span. It grows as an epiphyte on the trunks and branches of trees, and occasionally as a lithophyte on mossy rock, in cool, humid evergreen and mixed montane forest. The species experiences a pronounced cool, dry winter rest; the photographed material from the Mo-Chu valley in Bhutan at about 1880 m and from Lachung in Sikkim at 2660 m, both in June, illustrates its occupation of mid-elevation temperate forest and its early-summer flowering.

The plant produces tufted, slender, erect or arching cane-like stems that are conspicuously jointed and somewhat swollen at the nodes, giving the necklace-like appearance evoked by the epithet. The stems are leafy above, the leaves narrowly lanceolate, thin-textured and deciduous, leaving the older canes bare. The flowers are borne singly or in pairs from the nodes of leafless stems, fragrant, and variable in colour from white to pale pink, cream or yellowish. The sepals and petals are spreading; the trilobed labellum is often marked with reddish or greenish spots and bears a hairy or warty disc, while the short column has a foot forming a mentum. The fruit is a small ellipsoid capsule.

Highly polymorphic across its enormous range, D. moniliforme is placed in Dendrobium section Dendrobium and has accumulated extensive synonymy, with numerous regional forms and horticultural selections; the alternative name appearing on the source link reflects this nomenclatural complexity. Long cultivated in East Asia and esteemed for its fragrance and cold-hardiness, it remains widespread, but localised populations are reduced by collection and habitat loss.

Author: (L.) Sw. · Sources: POWO (Kew), GBIF, Flora of China, The Orchids of Bhutan (Pearce & Cribb), Dendrobium and its Allies (Lavarack et al.)

Orchideaceae

Dendrobium nobile

by GP Jürgens

Lindl.

Bhutan2014 170
Bhutan Trashiyangtse 2120m, May
Sikkim2004 441 G769
Sikkim/India Tista-Valley 2400m May
Sikkim2004 442 P770
Sikkim/India Tista-Valley 2400m May

Description

Dendrobium nobile is a widespread epiphytic orchid of the Himalaya and Indochina, native to China, India, Bhutan, Nepal, Myanmar, Vietnam and Laos, and now cultivated and naturalised far beyond, with records reported from many countries reflecting its enormous horticultural popularity. In the wild it grows as an epiphyte on mossy tree trunks and on shaded rocks in subtropical to warm-temperate broadleaved forest, chiefly between about 1000 and 2500 m. The plants documented here come from Trashiyangtse in eastern Bhutan at 2120 m and from the Tista Valley in Sikkim at 2400 m, both flowering in May at the close of the dry season.

The plant forms clustered, erect to pendulous, cane-like pseudobulbous stems that are fleshy, jointed and longitudinally grooved, bearing distichous, oblong-lanceolate leaves along their length; the leaves are usually deciduous before flowering. Inflorescences arise from the nodes of the leafless canes, each short raceme bearing one to three large, showy, fragrant flowers. The sepals and petals are white to rose-pink, deepening toward the tips, while the broad, rounded labellum is downy and conspicuously marked with a deep maroon-purple blotch in its throat ringed by paler margins. The column is short and the pollinia waxy; the fruit is an elongate dehiscent capsule releasing dust-like seeds.

As the nomenclatural type of section Dendrobium, this species is among the most important and intensively bred orchids in cultivation, with countless hybrids and named clones. Wild populations, however, have been heavily depleted by over-collection for horticulture and traditional medicine, and the species is listed on CITES Appendix II. Continued habitat loss across its native range makes in-situ conservation and sustainable trade regulation a significant concern.

Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of China, The Orchids of Bhutan (Pearce & Cribb), Flora of Bhutan, CITES Appendices, Dendrobium monograph

Hydrangeaceae

Deutzia staminea

by GP Jürgens

R.Br. ex Wall.

Nepal 97 304 P605
Nepal Honggaon 2360m, May

Description

Deutzia staminea is a deciduous shrub distributed across the western and central Himalayas, from Pakistan through northern India and Nepal to Bhutan, with populations extending into southwest China and northern Myanmar. GBIF records approximately 390 occurrences, with the majority from India and Nepal. The species occupies dry to mesic slopes, open forests, scrublands, and rocky hillsides at elevations of 1,500–3,200 m. At Honggaon in central Nepal at 2,360 m, it inhabits open Pinus–Quercus forests and rocky banks, where it flowers prolifically in May during the pre-monsoon season.
Deutzia staminea is a deciduous shrub reaching 1.5–4 m in height, with greyish-brown bark that exfoliates in thin flakes on older stems. Leaves are opposite, ovate to lanceolate, 3–8 cm long, with serrate margins and a rough texture from stellate trichomes on both surfaces. The inflorescence is a terminal corymb or panicle of 5–20 flowers. Flowers are pentamerous, 12–18 mm in diameter, with white petals that are oblong-elliptic and spreading. The stamens, 10 in number, are distinctive: the filaments are broadly winged and toothed at the apex, exceeding the petals — a character reflected in the specific epithet 'staminea.' The fruit is a hemispheric capsule, 4–6 mm across, dehiscing by 3–4 valves and releasing numerous small seeds.
Deutzia staminea is the most widespread Himalayan representative of the genus and is distinguished from the closely related D. compacta by its prominently toothed stamen filaments and generally laxer inflorescences. The species serves as an important early-season nectar resource for pollinators in mid-elevation Himalayan landscapes, where relatively few shrubs are in flower during the pre-monsoon period. It is occasionally cultivated in European gardens and has been in cultivation since its introduction by Wallich in the early nineteenth century.

Author: R.Br. ex Wall. · Sources: POWO (Kew), GBIF, Flora of China Vol. 8, Flora of Pakistan Vol. 192, Polunin & Stainton: Flowers of the Himalaya (1984)

Ranunculaceae

Dichocarpum adiantifolium

by GP Jürgens

(Hook.f. & Thomson) W.T.Wang & P.K.Hsiao

Nepal 97 310 G614
Nepal Honggaon 2300m May
Sikkim 2006 33 2 ergebnis
India West-Bengal Tonglu 3200m, May

Description

Dichocarpum adiantifolium is a slender woodland buttercup relative of the Sino-Himalayan region, distributed through Taiwan, China, India, Nepal, Bhutan and Myanmar, with the comparatively rich total of about 286 GBIF records. It grows in cool, shaded, humus-rich situations: moist temperate forest floors, mossy rocks, ravine banks and streamsides, generally between about 2000 and 3500 m. The collections illustrated, from Honggaon in Nepal at around 2300 m and Tonglu in West Bengal at about 3200 m, both in May, represent its typical spring-flowering forest habitat.

It is a delicate, glabrous perennial herb arising from a short rhizome. The leaves are mostly basal, long-petiolate and compound, divided into numerous small, thin, fan-shaped to obovate leaflets that recall the fronds of a maidenhair fern (Adiantum), hence the epithet. Slender scapes bear loose, few-flowered cymes of small flowers, each with five white, petaloid sepals and small tubular or two-lipped nectary petals, numerous stamens and usually two carpels. The diagnostic fruit is a pair of divergent, flattened follicles spreading widely at maturity, a feature reflected in the generic name (from the Greek for divided fruit).

Dichocarpum is a small east Asian and Himalayan genus segregated from Isopyrum and allied to Thalictrum and Aquilegia within the Ranunculaceae; D. adiantifolium was originally described under Isopyrum and later transferred by Wang and Hsiao. The paired spreading follicles and ferny foliage make it readily recognisable. It is a fairly widespread forest-understorey species and is not regarded as threatened, though as a shade-demanding mesophyte it depends on intact, humid temperate forest and would be sensitive to logging and forest fragmentation.

Author: (Hook.f. & Thomson) W.T.Wang & P.K.Hsiao · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Wang & Hsiao Revision of the Genus Dichocarpum

Didymocarpinae

Didymocarpus oblongus

by G & P Jürgens

Wall.

Sikkim 2006 449 ergebnis
India West-Bengal, Tolung 2450m, May

Description

Didymocarpus oblongus is a relatively uncommon gesneriad endemic to the eastern Himalaya, recorded from Nepal, northeast India (Sikkim, Darjeeling, Assam), Bhutan, and adjacent parts of southern China (Xizang, Yunnan). It inhabits shaded, damp rock faces, mossy cliff ledges, and steep earth banks in montane broadleaved and mixed forests, typically at elevations between 1,800 and 3,000 m. The species has been documented from the Tolung area of West Bengal at approximately 2,450 m, where it grows in the moist understorey of temperate forests during the spring season.
The plant is a perennial herb with a short, erect stem 5–15 cm tall, arising from a fleshy rootstock. Leaves are arranged in an opposite, often crowded rosette-like cluster near the stem apex; they are oblanceolate to oblong, 5–15 cm long and 2–5 cm wide, with a crenate to serrate margin, the upper surface dark green and sparsely pilose, the lower surface paler and more densely pubescent. The inflorescence is a lax cyme of 2–6 flowers borne on a slender peduncle 5–10 cm long. The calyx is tubular, five-lobed. The corolla is tubular-funnelform, 2–3 cm long, typically pale purple to lavender with darker markings in the throat. Stamens are two, with the filaments inserted at mid-tube; the anthers are coherent face to face. The fruit is a slender, elongate capsule 2–4 cm long, dehiscing loculicidally.
Didymocarpus is a genus of approximately 100 species centred in mainland Asia, with the Himalayan region representing a significant centre of diversity. D. oblongus is distinguished from allied species by its oblong leaf shape, relatively long peduncles, and high-elevation habitat preference. With only 88 occurrence records in GBIF and a restricted distribution along the eastern Himalayan arc, the species warrants conservation attention, particularly as its cliff-face and forest-understorey habitats are sensitive to deforestation and landslide disturbance.

Author: Wall. · Sources: POWO (Kew), GBIF, Flora of Bhutan Vol. 2, Flora of China Vol. 18, Möller & Clark: Gesneriaceae classification (2013)