Tag:

Montane (1500-2500 m)

Combretaceae

Terminalia myriocarpa

by GP Jürgens

Van Heurck & Müll. Arg.

Bhutan2015 170
Bhutan Zhemgang 950m, October
Bhutan2012 783
Bhutan Zemgang 1800m, October

Description

Terminalia myriocarpa Van Heurck & Mull.Arg. is a large evergreen tree of the Combretaceae, distributed across the eastern Himalaya and Indo-Burmese region, ranging from northeastern India, Nepal and Bhutan through Myanmar, Thailand, Laos and Vietnam to southwestern China (GBIF: c. 454 occurrences). It is a canopy tree of subtropical and tropical moist evergreen forests, favouring deep, moist soils along streams and in foothill valleys, generally below about 1,500 m though ascending higher locally. The photographed trees from Zhemgang in central Bhutan, recorded at about 950 m and 1,800 m in October, illustrate its presence in the warm, humid forests of the southern foothills.

The tree is tall, reaching 30 m or more, frequently developing prominent buttresses at the base. The leaves are opposite or subopposite, oblong-elliptic, with an acuminate apex and entire to crenulate margins, and often bear a pair of glands near the base of the petiole. The flowers are small, numerous and bisexual, borne in large, much-branched terminal and axillary panicles, giving rise to the species epithet "myriocarpa" ("many-fruited"). The fruit is a small, two-winged, samaroid nutlet that turns pink to crimson in dense masses, a striking feature that aids wind dispersal.

Terminalia belongs to the pantropical Combretaceae and includes many ecologically and economically important timber trees. Terminalia myriocarpa yields a useful general-purpose hardwood and is a significant component of lowland evergreen forest. Although locally common over a wide range and not globally threatened, its lowland forest habitat is under pressure from logging and land conversion across parts of its distribution.

Author: Van Heurck & Müll. Arg. · Sources: POWO (Kew), Flora of China Vol. 13, Flora of Bhutan Vol. 2, Flora of Nepal, GBIF, Exell: Combretaceae revisions

Trochodendraceae

Tetracentron sinense

by GP Jürgens

Oliv.

Bhutan2015 34
Bhutan Thimphu 2200m, October
Bh2008 43 G76
Bhutan Thimphu 2200m, April
Bh09 209 P350
Bhutan Thimphu 2200m, April

Description

Tetracentron sinense is a deciduous tree of the eastern Himalaya and the mountains of central and southwestern China, recorded by GBIF from China, Nepal, Bhutan, India, Myanmar and Vietnam (with cultivated records in Europe and North America) across about 940 georeferenced occurrences. It is a tree of cool, moist temperate broadleaf and mixed forest, growing in valleys, on shaded slopes and along streamsides, generally between about 1,700 and 3,500 m. The cited records from Thimphu in western Bhutan at around 2,200 m, photographed in both April and October, span the leafing-out and the autumnal phases of its annual cycle and place it well within the temperate forest belt of the inner Himalaya, where it occurs scattered among other broadleaved trees.

The tree has a straight trunk and bears its leaves in two kinds of position: simple, alternate, long-petioled leaves on long shoots and solitary leaves terminating short spur shoots. The leaves are ovate to broadly ovate, cordate at the base, acuminate, finely serrate, and conspicuously palmately veined from the base. The minute, perfect flowers are densely crowded on slender, pendulous, catkin-like spikes; each tetramerous flower has four tepals, four stamens and a four-carpellate ovary. The fruit is a small four-locular capsule that splits to release tiny winged seeds. Anatomically the wood is remarkable for being vesselless, the water-conducting tissue consisting only of tracheids.

Tetracentron sinense is one of only two genera in the small, isolated family Trochodendraceae (the other being Trochodendron), an ancient and phylogenetically basal lineage of eudicots whose vesselless wood is regarded as a primitive or secondarily reduced condition of great interest to plant systematists and to studies of angiosperm wood evolution. As a relict species with a disjunct, fragmented distribution, it is of significant conservation concern: it is legally protected in China and assessed as near-threatened, its populations reduced by logging and habitat loss, making it an emblematic "living-fossil" tree of the East Asian temperate flora.

Author: Oliv. · Sources: POWO (Kew), GBIF, Flora of China Vol. 6, Flora of Bhutan Vol. 1, Flora of Nepal, Flora of Pakistan, Endress: systematics and floral morphology of Trochodendraceae

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

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

Cornaceae

Toricellia tiliifolia

by GP Jürgens

DC.

Bhutan2014 272
Bhutan Trithangebe 700m, May
Bh2008 541 G819
Bhutan Limbukha 2200m April

Description

Toricellia tiliifolia DC. is a small deciduous tree or large shrub of the Cornaceae (or the segregate family Toricelliaceae), restricted to the Himalaya and southwestern China. GBIF records, totalling 23 occurrences, place it in China, Nepal, Bhutan and India. The species grows on moist, often disturbed slopes, ravine margins, forest edges and streamsides through the subtropical to lower temperate belt, broadly from 700 to 2,300 m. The cited Bhutanese collections from Trithangebe at 700 m in May and from Limbukha at 2,200 m in April illustrate this altitudinal span across the southern Bhutanese foothills.

The plant is a soft-wooded tree with stout, somewhat pithy branchlets and conspicuous leaf scars. The leaves are alternate, long-petiolate, broadly ovate to orbicular with a cordate base, palmately veined and shallowly lobed with a serrate margin, recalling those of a lime (Tilia), hence the epithet; the petiole base is dilated and sheathing. The plant is functionally dioecious, the small greenish flowers borne in long, slender, pendulous panicles; staminate flowers have minute petals and stamens, while the pistillate flowers have a reduced perianth and an inferior ovary. The fruit is a small ovoid drupe crowned by the persistent styles.

Toricellia is a relictual, taxonomically isolated genus whose placement has shifted between Cornaceae, Araliaceae and its own family Toricelliaceae within the Apiales, reflecting an ambiguous combination of cornoid and aralioid characters. Its disjunct, narrow Sino-Himalayan distribution makes it of considerable biogeographic interest as a Tertiary relict, and although not formally assessed as threatened, its limited range warrants attention where lower-montane forests are being cleared.

Author: DC. · Sources: POWO (Kew), GBIF, Flora of China Vol. 14, Flora of Bhutan Vol. 2, Flora of Nepal, Eyde: Comparative anatomy and phylogeny of the Cornaceae

Asteraceae

Tragopogon gracilis

by G & P Jürgens

D.Don

Garh 07 34 ergebnis
India Garhwal Ransi at Mandakini 2000m, June

Description

Tragopogon gracilis is a slender goatsbeard of the western and central Asian mountains, distributed from Afghanistan (AF), Pakistan (PK) and the western Himalaya of India (IN) and Nepal (NP) through China (CN), Tajikistan (TJ), Kyrgyzstan (KG) and Iraq (IQ) into Russia (RU), with 312 GBIF occurrences. It grows on open grassy slopes, meadows, fields and disturbed ground in the temperate and subalpine zones. The illustrated plant was recorded in the Indian Garhwal Himalaya at Ransi above the Mandakini at about 2000 m in June, where it flowers in early summer.

It is an erect annual to biennial or short-lived perennial herb with milky latex and a slender, often sparingly branched stem. The leaves are linear to linear-lanceolate, grass-like, sheathing at the base and tapering to a fine point. The capitula are solitary and terminal, subtended by a single row of lanceolate involucral bracts that frequently exceed the ligules; all florets are ligulate (the head homogamous), yellow and sometimes purple-tinged on the outer face. The fruit is a long, beaked cypsela bearing a feathery, plumose pappus of plumose bristles that forms the conspicuous spherical seed-head typical of the genus.

Tragopogon belongs to tribe Cichorieae of Asteraceae, a group characterised by latex and ligulate florets. The genus is well known to botanists for recurrent allopolyploid speciation, and its Central Asian and Irano-Turanian species, including T. gracilis, form part of the steppe and mountain-meadow flora at the Himalayan range margin, of biogeographic interest as a western element extending into the high Himalaya.

Author: D.Don · Sources: POWO (Kew), GBIF, Flora of Pakistan, Flora of China, Flora Iranica, Monograph of the genus Tragopogon

Araliaceae

Trevesia palmata

by GP Jürgens

(Roxb. ex Lindl.) Vis.

Bhutan2015 591
Bhutan Mo-Chu 1900m, October
Sikkim 2006 308 ergebnis
India West-Bengal, Chaana 1750m, May

Description

Trevesia palmata, the snowflake tree, is a tropical and subtropical Asian aralioid ranging from the Himalaya of Nepal, India and Bhutan through Bangladesh, Myanmar, Thailand, Laos, Cambodia, Vietnam, southern China and into Malaysia, with more than 700 GBIF occurrences including many from cultivation in botanic gardens worldwide. It grows in warm, humid broadleaved forest, in ravines, along streams, on shaded slopes and in clearings on moist, fertile soils. The localities illustrated, the Mo Chu valley in Bhutan at about 1900 m in October and Chaana in West Bengal at 1750 m in May, are typical of its lower-montane belt of roughly 500-2000 m in the eastern Himalaya.

It is a small, sparsely branched evergreen tree or treelet, often prickly on the trunk and petioles, with a stout pithy stem. The very large leaves are palmately lobed and again deeply incised, so that each is divided almost to the centre into spreading, toothed segments arranged like a snowflake, borne on long prickly petioles and clustered toward the stem apex. The numerous small flowers are creamy to greenish-white and grouped in dense globose umbels arranged along a large, branched terminal panicle. Each flower has a fleshy disc and an inferior ovary of several carpels, and the fruit is a small, somewhat ribbed, fleshy drupe containing several seeds.

Trevesia is a small genus of the ivy family centred on tropical Asia, and T. palmata is its most familiar and widespread species. The dramatically dissected juvenile foliage makes it a popular ornamental and conservatory plant, which explains the many cultivated records far outside its native range. In its forest habitat it is an understorey to mid-canopy element pollinated by insects, and its fruits are dispersed by birds and other animals.

Author: (Roxb. ex Lindl.) Vis. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Frodin & Govaerts World Checklist of Araliaceae, Hooker Flora of British India

Asteraceae

Tricholepis furcata

by GP Jürgens

DC.

Bhutan2015 462
Bhutan Trongsa 2100m, October
Bhutan2012 1326
Bhutan Pemagatse 1900m, October

Description

Tricholepis furcata is a thistle-like composite of the Himalaya and adjacent regions, recorded from India, Nepal, Bhutan, Pakistan and China, with 148 georeferenced occurrences. It is a plant of open, sunny, often dry situations, occupying grassy hill slopes, scrub, rocky banks, roadsides and disturbed ground in the subtropical to lower temperate zone, typically between about 1000 and 2500 m. It was photographed near Trongsa at 2100 m and Pemagatse at 1900 m in Bhutan in October, flowering at the close of the monsoon when many montane composites reach their peak on warm, well-drained slopes.

It is an erect, branched perennial or biennial herb, the slender striate stems often forking (furcate) above and bearing alternate, narrow, entire to pinnately divided leaves that are roughly hairy and frequently decurrent on the stem. The flower heads are solitary or few at the branch tips, with an ovoid involucre of many imbricate bracts whose tips are characteristically fringed or laciniate, a diagnostic feature of the genus Tricholepis. All florets are tubular (discoid) and pink to purple, the corolla deeply five-lobed. The fruit is a small obovoid cypsela crowned by a pappus of barbellate or plumose bristles.

The genus Tricholepis belongs to tribe Cardueae (the thistle tribe) and is centred on the Indian subcontinent and Iran, allied to Centaurea and Saussurea. The fimbriate phyllary tips that give the genus its name ("hairy scale") separate it from related cardueoid genera. Ecologically the species is a coloniser of open and disturbed slopes and contributes to autumn-flowering grassland communities. It is widespread and common, of no conservation concern.

Author: DC. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of Pakistan, Compositae monograph (Cardueae, in The Families and Genera of Vascular Plants)

Melanthiaceae

Trillium tschonoskii

by GP Jürgens

Maxim.

Bh2008 35 P57
Bhutan Doch-La, 3000m April
Bh09 212 G355
Bhutan Paro, 2400m June

Description

Trillium tschonoskii is a wide-ranging woodland herb of temperate East and South Asia, distributed from Japan, Korea and Taiwan through eastern and central China and into the Himalaya, reaching India, Bhutan and Nepal, with records also from the Russian Far East. With more than two thousand GBIF occurrences it is by far the most widespread Asian trillium, though it thins markedly toward its western Himalayan limit. It is a plant of cool, shaded, humus-rich broadleaved and conifer forest, favouring moist slopes and stream banks, generally between about 2300 and 3600 m in the Himalaya. The Bhutanese material illustrated, from Doch-La at 3000 m in April and from Paro at 2400 m in June, spans the species' flowering season as it tracks elevation, emerging soon after snowmelt in the deep shade of the forest floor.

The plant is a glabrous perennial arising from a short, thick, horizontal rhizome, producing a single erect stem that bears at its summit a single whorl of three broadly rhombic to ovate, net-veined, sessile or short-stalked leaves. Above this whorl a solitary flower is borne on a short erect pedicel. The flower is trimerous, with three green, lanceolate sepals and three white (sometimes ageing pinkish) ovate petals; six stamens with prominent anthers surround a superior, three-locular ovary topped by three recurved stigmas. The fruit is a fleshy, ovoid, reddish to dark berry-like capsule containing numerous seeds, each bearing an oily elaiosome that promotes dispersal by ants.

Trillium, now placed in the Melanthiaceae, is a classic component of the temperate deciduous forest flora of the Northern Hemisphere, and T. tschonoskii is the principal Asian representative reaching the Himalaya, exemplifying the floristic links between East Asian and Sino-Himalayan woodlands. Its slow growth, dependence on undisturbed forest humus and ant-mediated seed dispersal make it sensitive to habitat disturbance, and like many trilliums it has horticultural appeal and some traditional medicinal use of the rhizome, which can drive local collection. Although broadly distributed and not globally threatened, its peripheral Himalayan populations warrant monitoring as forest cover and microclimate change.

Author: Maxim. · Sources: POWO (Kew), GBIF, Flora of China Vol. 24, Flora of Bhutan Vol. 3 Part 1, Flora of Nepal, Trillium (Frederick W. Case and Roberta B. Case)