Tag:

Summer

Asteraceae

Tanacetum atkinsonii

by GP Jürgens

(C.B.Clarke) Kitam.

Sikkim2003 135 P183
India Sikkim Dzongri 4000m, August

Description

Tanacetum atkinsonii is an aromatic alpine composite of the Himalaya, recorded from Nepal, India, Bhutan and southern China, with GBIF holding around 102 occurrences across this range. It grows on open, stony alpine slopes, rocky pastures, screes and dry grassy banks in the high alpine zone, generally between about 3500 and 4500 m, where it tolerates strong insolation, cold and free-draining substrates. The illustrated plant from Dzongri in Sikkim at 4000 m, flowering in August, is characteristic of these exposed high-altitude habitats and of its late-summer flowering after the monsoon.

It is a perennial, aromatic herb with a woody rootstock producing erect to ascending stems and finely divided, pinnately dissected or bipinnatisect leaves that are grey-green and often hairy, releasing a tansy-like scent when crushed. The capitula (flower heads) are borne in a terminal corymb; each head has an involucre of imbricate, scarious-margined bracts and the typical Tanacetum structure of yellow disc florets, with the marginal florets reduced or shortly rayed rather than conspicuously ligulate. The fruit is a small, ribbed, glandular cypsela, usually with a short membranous corona rather than a true pappus.

Transferred to Tanacetum by Kitamura from an original placement under Chrysanthemum/Pyrethrum by C.B. Clarke, the species sits within the taxonomically fluid tansy group of the tribe Anthemideae, distinguished by its dissected aromatic foliage and reduced ray florets. A widespread high-Himalayan element, it is of no particular conservation concern.

Author: (C.B.Clarke) Kitam. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Compositae of the Himalaya (specialist treatments)

Asteraceae

Taraxacum sikkimense

by G & P Jürgens

Hand.-Mazz.

Sikkim2003 512 G712 2 ergebnis
Sikkim Yumedzandong 4500m, August

Description

Taraxacum sikkimense is a high-alpine dandelion of the Himalaya and Tibetan Plateau margins, recorded from China, India, Nepal, Bhutan and Pakistan, with a modest set of records (c. 128 in GBIF) reflecting its restricted high-elevation range. It occupies alpine meadows, turfy slopes, moist gravelly ground and the surrounds of snowmelt flushes, typically between about 4000 and 4800 m. The photographed plant from Yumedzandong in Sikkim, at 4500 m and flowering in August, exemplifies the species in its short alpine growing season, when warmth and meltwater briefly permit growth and flowering near the upper limit of vascular plant life.

The plant is a small, acaulescent, rosette-forming perennial herb with a thick, often blackened taproot and a milky white latex characteristic of the tribe Cichorieae. The leaves are all basal, runcinate to pinnatifid or shallowly toothed, sometimes nearly entire in dwarfed alpine forms. The flowering scapes are short, each bearing a single capitulum subtended by an involucre of imbricate phyllaries, the outer often appressed or recurved with a coloured margin. The capitulum is homogamous, composed entirely of yellow ligulate (ray) florets; the fruit is a ribbed, spinulose-muricate cypsela narrowed above into a slender beak that bears a pappus of simple white bristles, dispersed by wind.

Taraxacum is a taxonomically formidable genus owing to widespread apomixis (agamospermy) and polyploidy, which generate innumerable stable microspecies; the Himalayan high-elevation taxa form a distinctive assemblage that remains incompletely revised. Taraxacum sikkimense belongs to this alpine radiation. As a specialised high-altitude plant with a naturally fragmented distribution, it is potentially sensitive to alpine habitat change, though it has not been formally assessed.

Author: Hand.-Mazz. · Sources: POWO (Kew), GBIF, Flora of China (Asteraceae), Flora of Bhutan, Taraxacum: A monograph (Richards)

Loranthaceae

Taxillus kaempferi

by GP Jürgens

(DC.) Danser

Bh09 415 P653
Bhutan Paro, 2400m June

Description

Taxillus kaempferi is a stem-hemiparasitic mistletoe ranging from Japan and Taiwan across China to the eastern Himalaya, with GBIF records from Japan, China, Taiwan, Bhutan and India. It parasitises the branches of trees and shrubs, particularly conifers such as Pinus and Tsuga as well as various broad-leaved hosts, in temperate montane forest generally between 1,500 and 2,800 m. The photographed plant grows near Paro in western Bhutan at about 2,400 m in June, representing the species at the western limit of its distribution in the Himalayan conifer belt.

The plant forms a pendent to spreading shrub attached to the host branch by a haustorial union and often by epicortical runners. The young branchlets, leaf undersides and inflorescences are clothed in a dense rusty to reddish stellate or dendritic tomentum, a key generic feature. The leaves are leathery, alternate to subopposite, ovate to elliptic with entire margins. The flowers are borne in short axillary umbels or racemes; each has a tubular, four-merous corolla that is reddish to orange and curved, splitting into recurved lobes at anthesis to expose the stamens, and is pollinated chiefly by birds. The fruit is a one-seeded berry with viscid pulp, dispersed by frugivorous birds that wipe the sticky seed onto new branches.

Taxillus belongs to the Loranthaceae, the showy aerial-parasite family, and is distinguished from related genera by its tomentum, umbellate inflorescence and floral structure. As a hemiparasite it retains chlorophyll while drawing water and minerals from the host. Though it can locally affect host vigour, T. kaempferi is a natural and widespread forest element, ecologically valuable as a nectar and fruit resource, and is not of conservation concern.

Author: (DC.) Danser · Sources: POWO (Kew), GBIF, Flora of China Vol. 5 (Loranthaceae), Grierson & Long: Flora of Bhutan Vol. 1, Barlow: Loranthaceae of Asia (taxonomic revisions)

Apiaceae

Tetrataenium nepalense

by GP Jürgens

(D.Don) Manden.

Bh09 71 P123
Bhutan Jili-La 3600m, June

Description

Tetrataenium nepalense is a tall Himalayan umbellifer distributed from Nepal and northern India through Bhutan into south-western China and Myanmar. Its 266 GBIF records lie within this native arc, indicating a widespread montane species of the Eastern and Central Himalaya. It occupies subalpine and alpine meadows, open slopes, forest margins and clearings, generally between about 3000 and 4000 m, where it is a characteristic robust herb of moist high-altitude grassland. The plant photographed at Jili-La in Bhutan at about 3600 m in June illustrates the species at its early-summer flowering on these damp, herb-rich montane slopes.

It is a stout, erect biennial or perennial herb arising from a thick taproot, with hollow, ridged, often pubescent stems. The large leaves are pinnate to ternately compound, the broad leaflets ovate, lobed and toothed, the lower leaves long-petiolate with conspicuous sheathing bases. The inflorescence is a large terminal compound umbel with numerous rays; the small white flowers are often radiant, the marginal petals of the outer flowers enlarged. The fruit is a flattened, broadly ovate to obovate, dorsally compressed schizocarp with conspicuous oil ducts (vittae) and narrowly winged lateral ribs.

Long known as Heracleum nepalense (a name preserved in its WordPress URL), the species was transferred to the segregate genus Tetrataenium, distinguished from Heracleum by features of the vittae and fruit. Its hogweed-like habit and large radiant umbels are typical of the group. Widespread and locally common across its range, T. nepalense is not considered threatened and is a prominent component of high Himalayan meadow vegetation.

Author: (D.Don) Manden. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Pimenov & Kljuykov Umbelliferae revision

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 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