Tag:

Bhutan

Flowers of Bhutan — 1326 plant species documented across the Bhutanese Himalaya, from dense broadleaf and conifer forests to alpine scrub and meadows. Bhutan’s largely intact wilderness shelters an exceptional diversity of orchids, rhododendrons, primulas and Himalayan poppies, many of them regional endemics. Each species page includes a botanical description, distribution, habitat and flowering time, with the original photograph and its recorded altitude and locality.

Ranunculaceae

Thalictrum javanicum

by GP Jürgens

Blume

Bhutan2012 407
Bhutan Wangdi 2500m, June

Description

Thalictrum javanicum Blume is a widespread meadow-rue ranging across tropical and subtropical Asia. GBIF documents some 1366 occurrences from India, Sri Lanka, Nepal, Bhutan, Myanmar and southern China through Taiwan, Japan and into the Malesian uplands of Indonesia. It occupies moist, shaded habitats: streamsides, forest floors, damp ravines, clearings and grassy banks, mainly at middle elevations between roughly 1500 and 3000 m, descending lower in the tropics. The plant photographed near Wangdi in Bhutan at 2500 m in June, during the early monsoon, reflects its association with the cool, humid broad-leaved and conifer forest belt of the Himalaya.

It is a glabrous perennial herb forming erect stems 30-100 cm tall from a short rhizome. The leaves are two- to four-times ternately compound, the ultimate leaflets obovate to suborbicular, three-lobed and crenate at the apex, thin in texture, with conspicuous stipels at the divisions of the petiole. The inflorescence is a lax terminal panicle of small, apetalous flowers; the perianth consists of inconspicuous, caducous greenish sepals, the floral display provided instead by the numerous spreading stamens with slender filaments and oblong anthers. The fruit is a cluster of sessile to shortly stipitate, ribbed, ellipsoid achenes tipped by a short curved beak.

Thalictrum is a large, taxonomically intricate genus characterised by reduced, wind- and generalist-insect-pollinated flowers and considerable variation in stamen and achene morphology, generating a complex synonymy across its broad range. T. javanicum is among the most ecologically plastic species, tolerating a wide altitudinal and geographic span, which accounts for its abundant collection record. It is a common, unthreatened component of Asian montane forest understoreys, and several Thalictrum species, including this one, contain isoquinoline alkaloids used in regional ethnomedicine.

Author: Blume · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Flora of Java, Annotated Checklist of the Flowering Plants of Nepal

Ranunculaceae

Thalictrum leuconotum

by GP Jürgens

Franch.

BhutanPG2011 817 01 01
Bhutan Chele-La, 3700m July

Also: Iris Clarkei Hook.f.

Description

Thalictrum leuconotum is an alpine meadow rue distributed across the eastern Himalaya and adjacent Sino-Himalayan ranges, with verified records from China, Nepal and Bhutan (GBIF documents some 152 occurrences). It inhabits subalpine and alpine meadows, open grassy slopes, forest margins and the rocky banks of seasonal streams, typically between about 3000 and 4200 m. The species was photographed on the Chele-La in western Bhutan at 3700 m in July, a high pass where it flowers among dwarf rhododendron scrub and herbaceous turf during the brief growing season.

The plant is an erect perennial herb arising from a short, fibrous-rooted rhizome, the stems glabrous to minutely pubescent and branched in the upper part. The leaves are several times ternately compound, the ultimate leaflets thin, obovate to suborbicular and shallowly lobed or crenate, often glaucous and conspicuously whitish beneath, a feature alluded to in the epithet "leuconotum" (white-backed). The inflorescence is a lax, spreading panicle of small apetalous flowers; the showy parts are the numerous pendulous stamens with slender filaments, while the four caducous sepals are greenish to purplish. The fruit is a cluster of small, ribbed, stipitate achenes.

Within Thalictrum, a large and taxonomically intricate genus, T. leuconotum belongs to the broad assemblage of Sino-Himalayan species characterised by reduced perianths and reliance on wind pollination. Its glaucous, white-backed foliage and montane ecology distinguish it from sympatric congeners. As a widespread high-elevation herb of relatively undisturbed alpine pastures, it is not considered threatened, though localised grazing pressure and habitat change may affect populations across its range.

Author: Franch. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Annotated Checklist of the Flowering Plants of Nepal, Monograph of Thalictrum (Boivin)

Ranunculaceae

Thalictrum reniforme

by G & P Jürgens

Wall.

Garw 2005 277 ergebnis
India Garhwal Kunol 2650m, October

Description

Thalictrum reniforme is a perennial herb distributed across the Himalayan arc from northern India through Nepal and Bhutan to southwestern China (Yunnan, Xizang, Sichuan). It occurs in moist, shaded habitats including forest margins, thickets, stream banks, and damp meadows at elevations of 1,800–3,500 m. The species is well represented in the western Himalayan foothills, as demonstrated by collections from Kunol in the Garhwal region of Uttarakhand, India, at 2,650 m, where plants have been observed in fruit as late as October.
The plant produces erect to ascending stems 30–80 cm tall from a short, fibrous-rooted rhizome. The leaves are bi- to triternately compound; the leaflets are distinctive for the genus, being reniform to orbicular, 1–3 cm wide, with a crenate to shallowly lobed margin. The leaflet surfaces are thin-textured and often glaucous beneath. The inflorescence is a lax, terminal panicle bearing numerous small, apetalous flowers. The sepals are four, ovate, greenish to purplish, caducous. The stamens are pendulous, with slender filaments and oblong anthers. The achenes are few per flower, stipitate, fusiform to obliquely ovoid, ribbed longitudinally, 3–5 mm long including the stipe.
Thalictrum reniforme is readily distinguished from most congeners by its conspicuously reniform leaflets, a character that inspired Wallich's specific epithet. The species belongs to a taxonomically challenging genus in which species boundaries are often obscured by morphological plasticity and hybridisation. With approximately 248 occurrence records in GBIF spanning India, Nepal, Bhutan, and China, it is moderately well collected. Ecologically, it contributes to the herbaceous understorey diversity of Himalayan temperate forests. No specific conservation concerns have been raised, though continued monitoring of its forest-dependent habitats remains advisable given ongoing pressures from logging and agricultural encroachment.

Author: Wall. · Sources: POWO (Kew), GBIF, Flora of China Vol. 6, Flora of Bhutan Vol. 1, Tamura: Thalictrum in Die Natürlichen Pflanzenfamilien (1995)

Ranunculaceae

Thalictrum rostellatum

by G & P Jürgens

Hook.f. et Thomson

BhutanPG2011 73

Description

Thalictrum rostellatum is a meadow-rue of the temperate to subalpine Himalaya and adjacent China, recorded from China, Nepal, India, Bhutan and Myanmar, with some 258 occurrences aggregated in GBIF. It favours shaded, humus-rich slopes, the margins of forest, scrub and streamsides, and damp grassy banks within the broad-leaved and conifer forest belt of the Eastern Himalaya. Across its range it ascends through the montane and lower subalpine zones, where it grows in the dappled understorey alongside other moisture-loving herbs, flowering through the summer monsoon months.

It is a slender, glabrous perennial herb with a thin, creeping rhizome and erect, sparingly branched stems. The leaves are ternately decompound, the ultimate leaflets thin and membranous, obovate to broadly cuneate and shallowly lobed or toothed at the apex, often glaucous beneath. The inflorescence is a lax, few-flowered panicle of small, nodding flowers; as in the genus, the four pale sepals are caducous and petals are wanting, the floral display reduced to the pendulous stamens with filiform filaments and delicate anthers. The carpels are few and stipitate, ripening into small, stipitate achenes that bear a conspicuous slender beak, the rostellum from which the epithet derives.

The markedly beaked, stalked achenes are the principal character separating T. rostellatum from related Himalayan meadow-rues such as T. virgatum and T. reniforme. Like most Thalictrum it is anemophilous, the reduced, scentless flowers and exserted stamens reflecting wind pollination. Widespread and locally frequent through the Eastern Himalaya, it is of no particular conservation concern, though as a forest-understorey element its persistence depends on intact montane woodland.

Author: Hook.f. et Thomson · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Boivin's revisionary studies of Thalictrum

Ranunculaceae

Thalictrum virgatum 

by G & P Jürgens

Hook. f. & Thomson

Nepal 99 893 ergebnis
West-Nepal Suli-Khola 2800m, July

Description

Thalictrum virgatum Hook.f. & Thomson is a widespread Sino-Himalayan meadow rue ranging from the Himalaya of Nepal, India and Bhutan eastward into south-western and central China; the comparatively large GBIF dataset of 498 occurrences attests to its abundance across the temperate Himalayan belt. It favours moist, shaded forest floors, streamsides, scrub margins and grassy slopes within the temperate to subalpine zone, broadly between 2400 and 4000 m. The photographed plant along the Suli-Khola in West Nepal at about 2800 m, flowering in July, is typical of its monsoon-season anthesis in the cool, humid, well-watered understorey of the moist temperate forest.

The species is a slender, erect, glabrous perennial herb with wiry, virgate stems arising from a short rootstock. The leaves are alternate and two- to three-pinnately compound, the ultimate leaflets small, thin, obovate to orbicular and shallowly three-lobed or crenate. The inflorescence is a lax, few-flowered, diffusely branched panicle or raceme; the small, pendulous flowers lack petals and instead bear four to five petaloid, caducous sepals that are whitish, pink-tinged or purplish. The numerous stamens have slender filaments and conspicuous anthers, giving the open flowers a delicate, dangling aspect. The fruit is a small cluster of stipitate, ribbed achenes.

Thalictrum is a large north-temperate genus of wind- and insect-pollinated petal-less Ranunculaceae, and T. virgatum belongs to the slender-stemmed, lax-panicled assemblage of the Sino-Himalaya. Its delicate habit and nodding pink-tinted flowers have brought it into specialist cultivation as a woodland ornamental. Being widespread, ecologically tolerant and locally common throughout the moist temperate Himalaya, it is of no conservation concern, and like many congeners it contains benzylisoquinoline alkaloids of pharmacological interest.

Author: Hook. f. & Thomson · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, B. A. Lecoyer — Monographie du genre Thalictrum

Fabaceae

Thermopsis barbata

by GP Jürgens

Benth.

Sikkim2011 151
Sikkim Kalep 3670m, June
Nepal 99 452 ergebnis
West-Nepal Naphukana 3080m, June

Description

Thermopsis barbata Benth. is a distinctive legume of the high Himalaya, occurring across China, India, Nepal and Bhutan. It is documented from Sikkim at Kalep around 3670 m and from West-Nepal at Naphukana near 3080 m, both flowering in June, within the subalpine to alpine belt. The species favours open stony slopes, dry grassy hillsides, gravelly pastures and the margins of alpine scrub, typically between 3000 and 4500 m, on well-drained, often disturbed substrates exposed to strong sun and seasonal aridity. Its roughly 606 GBIF records indicate a widespread but characteristically montane Himalayan range.

The plant is a robust perennial herb arising from a stout rootstock, the erect stems and foliage conspicuously clothed in long, soft, silky to villous hairs that give the epithet barbata. The leaves are palmately trifoliolate with elliptic to obovate leaflets and large persistent stipules. The flowers are arranged in a dense terminal raceme and are notably large for the genus, the papilionaceous corolla a deep purple to violet-maroon rather than the yellow usual in Thermopsis, subtended by hairy bracts and an enlarged calyx. The fruit is a hairy, flattened, several-seeded legume.

Thermopsis barbata is exceptional within its predominantly yellow-flowered, north-temperate genus for its dark purple corolla and dense pubescence, traits interpreted as adaptations to the cold, high-radiation alpine environment. Like many genistoid legumes it contains quinolizidine alkaloids that deter herbivores. Widespread and locally frequent across its range, it is not regarded as threatened, though high-altitude grazing and pasture degradation may locally affect populations.

Author: Benth. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Nepal, Flora of British India, Legumes of the World (Lewis et al.)

Asparagaceae

Theropogon pallidus

by GP Jürgens

(Wall. ex Kunth) Maxim.

Bh09 218 G366
Bhutan Wangdi 2250m, June
Nepal 99 897 ergebnis
West-Nepal Sepka 2760m, July
Sikkim 2006 453 ergebnis
India West-Bengal, Tolung 2200m, May

Description

Theropogon pallidus is the sole species of its genus, a rhizomatous woodland herb distributed along the Himalaya from Nepal through northern India, Bhutan and south-western China into Myanmar and Thailand. GBIF lists some 264 occurrences concentrated in Nepal, China, India and Bhutan, with outliers in Myanmar and Thailand. It grows in shaded, humus-rich soils of temperate broad-leaved and mixed forest, on mossy banks, ravine sides and beneath shrubbery, broadly between about 1800 and 3000 m. The accompanying images span its range, from Bhutan at Wangdi (2250 m, June) and West Nepal at Sepka (2760 m, July) to West Bengal at Tolung (2200 m, May), illustrating its early-summer flowering across the mid-montane forest belt.

The plant arises from a short, creeping rhizome and forms tufts of narrowly linear, grass-like basal leaves that are channelled, arching and somewhat fleshy. The flowering scape is erect and leafless, bearing a lax, secund raceme of pendulous, bell-shaped flowers; each flower is subtended by a membranous bract and hangs on a slender, jointed pedicel. The perianth is white to pale pink, the six tepals fused below into a campanulate tube with recurved lobes, enclosing six stamens with short filaments. The ovary is superior and trilocular, maturing into a globose, fleshy berry that ripens red, containing few rounded seeds.

Theropogon is a monotypic genus of the Asparagaceae (formerly Convallariaceae or Liliaceae sensu lato), morphologically intermediate between Ophiopogon and Convallaria and allied to the lily-of-the-valley group by its nodding campanulate flowers and berry fruit. Its disjunct, narrowly montane distribution makes it of biogeographic interest as a relict of Sino-Himalayan forest flora. The species is locally frequent and faces no broad conservation concern, though it depends on intact shaded forest understorey.

Author: (Wall. ex Kunth) Maxim. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, An Annotated Checklist of the Flowering Plants of Nepal, Genera of Convallariaceae

Cucurbitaceae

Thladiantha cordifolia

by GP Jürgens

(Blume) Cogn.

Bhutan2012 476
Bhutan Wangdi, 2500m September
Bhutan2015 63
Bhutan Wangdi, 2500m September
Bh09 229 P385
Bhutan Wangdi, 1600m June

Description

Thladiantha cordifolia is a climbing cucurbit distributed across the Sino-Himalayan and Indomalayan region, from Nepal, India, Bhutan and Bangladesh through Myanmar, Thailand, Vietnam, Laos and Malaysia into southern China, Indonesia and the Philippines; cultivated and casual records (ES, AU, JP, RO, DE, HU) inflate its GBIF country list, which rests on about 1,084 occurrences. The plants shown come from western Bhutan near Wangdue Phodrang, recorded at 1,600 m in June and 2,500 m in September, illustrating its altitudinal spread. It is a vine of forest margins, thickets, hedgerows and disturbed slopes in warm-temperate to subtropical country, typically between about 1,000 and 2,800 m, scrambling over shrubs and into the lower canopy.

It is a herbaceous to somewhat woody perennial climber arising from a tuberous rootstock, the stems angular and hispid and bearing simple or two-branched tendrils opposite the leaves. The leaves are cordate-ovate with a deeply cordate base, an acuminate apex and a denticulate margin, scabrid on both surfaces. The plant is dioecious; the male flowers are borne in axillary racemes and the females usually solitary, both yellow and campanulate with five-lobed corollas, the male flowers with the reduced stamen complement typical of the genus and the female with an inferior ovary. The fruit is an ovoid to oblong fleshy berry, often longitudinally ribbed and red at maturity, containing numerous flattened seeds.

Thladiantha is an Asian genus of the tribe Sicyoeae distinguished by its tuberous habit, dioecy and characteristic stamen arrangement. Its tubers and fruits have local food and medicinal uses. As a vigorous and widespread plant of secondary vegetation, T. cordifolia is not of conservation concern; indeed several Thladiantha species behave as garden escapes in temperate regions.

Author: (Blume) Cogn. · Sources: POWO (Kew), Flora of China Vol. 19, Flora of Bhutan Vol. 2, GBIF, Jeffrey: A review of the Cucurbitaceae

Acanthaceae

Thunbergia coccinea

by GP Jürgens

Wall. ex. D.Don.

Bhutan2012 363
Bhutan Wangdi 2500m, September

Description

Thunbergia coccinea Wall. ex D.Don is a vigorous woody climber of the eastern Himalaya and Indo-Burmese region, with GBIF documenting nearly 692 occurrences across India, China, Nepal, Bhutan, Myanmar, Thailand, Laos, Sri Lanka and Bangladesh, alongside numerous cultivated records in tropical and subtropical gardens worldwide. In the wild it scrambles through the canopy of moist broadleaved and subtropical forest, along streamsides and forest margins, flowering in the post-monsoon months. The illustrated plant from Wangdi (Wangdue Phodrang) in western Bhutan at 2500 m in September captures it at the upper edge of its altitudinal range, twining over shrubs and trees in humid hill forest.

The species is a perennial liana with twining stems and opposite, petiolate leaves that are ovate to cordate, acuminate, with toothed to entire margins and palmate basal venation. The flowers hang in long, pendulous, many-flowered racemes; each scarlet to brick-red corolla is tubular and curved with a slightly oblique, shortly five-lobed limb, subtended by paired bracteoles, and contains four didynamous stamens. The fruit is the characteristic acanthaceous capsule, beaked and explosively dehiscent, ejecting a few flattened seeds borne on retinacula.

Thunbergia, sometimes segregated in Thunbergiaceae but generally placed in Acanthaceae, comprises Old World tropical climbers and shrubs, several grown ornamentally; T. coccinea is valued in horticulture for its dramatic drooping red flower chains. Its bird- and insect-visited blooms point to a mixed pollination syndrome. The species is widespread and not of conservation concern, though as a forest liana it depends on the persistence of intact moist montane and submontane woodland.

Author: Wall. ex. D.Don. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Acanthaceae of the Indian Subcontinent, Bremekamp studies on Thunbergia

Saxifragaceae

Tiarella polyphylla

by GP Jürgens

D. Don

Bhutan2014 588
Bhutan Phobjika 2810m, May
Nepal 97 128 G222
Nepal Mewa-Khole 2500m April
Nepal 1994 194 ergebnis
Ost-Nepal Mewa-Khola 2100m April
Nepal 2001 252 ergebnis ergebnis
Nepal (Gorkha) Niuli Kharka 2700m, May

Description

Tiarella polyphylla is a perennial herb with a wide East Asian and Himalayan distribution, recorded from China, Japan, Korea, Taiwan, Nepal, India, Bhutan and Myanmar, and reliably documented by over 4300 GBIF occurrences. It is a plant of cool, shaded, humid forests, growing in moist humus-rich soil along streamsides, on mossy banks and in the understorey of broadleaved and mixed forest, generally between about 1500 and 3500 m. The photographed populations span Bhutan (Phobjika, 2810 m, May) and eastern and central Nepal (Mewa Khola 2100-2500 m, and Gorkha at Niuli Kharka 2700 m), flowering through the spring months.

The plant grows from a short rhizome and produces a basal rosette of long-petioled leaves; the lamina is cordate-orbicular, shallowly three- to five-lobed, with toothed margins and scattered hairs. The slender, erect flowering stem bears a few reduced cauline leaves and terminates in a narrow, elongate raceme of small flowers. Each flower has five white to greenish, narrow petals and conspicuously exserted stamens, giving the inflorescence a delicate, foamy appearance. The fruit is a distinctive two-valved capsule with markedly unequal valves, splitting to release the small seeds.

Tiarella is a small genus of the Saxifragaceae, and T. polyphylla is the principal Asian representative, the remaining species being North American; this disjunction is a classic example of the eastern Asian-North American floristic link. The plant is shade-tolerant and clonal, often forming loose colonies on forest floors. Though not threatened across its broad range, it depends on intact moist forest and is locally sensitive to logging and disturbance of streamside habitats.

Author: D. Don · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Saxifragaceae monograph