Tag:

Autumn

Ranunculaceae

Thalictrum chelidonii

by GP Jürgens

DC.

BhutanPG2011 384
Bhutan Shele-La, 3600m September
Bhutan2012 33
Bhutan Shele-La, 3600m September
Bhutan2012 325
Bhutan Dochu-La, 3600m September
Nepal 95 137 P230 ergebnis
Nepal South of Rupina La 3650m October

Description

Thalictrum chelidonii is a Himalayan meadow-rue distributed through Nepal, north-east India, Bhutan and south-west China, with 178 georeferenced occurrences. It grows in moist, often partly shaded sites along forest margins, in subalpine scrub, on grassy and rocky slopes and beside streams in the upper temperate to subalpine zones. The cited collections at Shele-La and Dochu-La in Bhutan (both about 3600 m, September) and south of Rupina La in Nepal (3650 m, October) reflect its typical altitudinal range of roughly 2700-4000 m, where it flowers and fruits late in the growing season.

It is an erect perennial herb with slender, branching, often glaucous stems and large, two- to three-times ternately or pinnately compound leaves; the leaflets are rounded to obovate, lobed and toothed, recalling those of Aquilegia. Unlike many wind-pollinated meadow-rues, T. chelidonii has conspicuous flowers in which the four or five petaloid sepals are well developed, lilac to rose-purple, surrounding numerous spreading stamens with slender filaments. The carpels are several and free, ripening into a cluster of stipitate, longitudinally ribbed achenes that hang on slender stalks.

Within Ranunculaceae the genus Thalictrum is distinctive for its apetalous flowers in which sepals and stamens provide the floral display; the showy coloured sepals of this species point to insect rather than purely wind pollination. The pendent, winged-ribbed achenes aid dispersal. Widespread and locally common across the central and eastern Himalaya, the species is of no conservation concern, and like several relatives it contains isoquinoline alkaloids of ethnomedicinal interest.

Author: DC. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Flora of Nepal, Tamura Ranunculaceae treatment (Die natürlichen Pflanzenfamilien)

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)

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

Linderniaceae

Torenia violacea

by GP Jürgens

(Azaola) Pennell

Bhutan2012 1338 ergebnis
Bhutan Pemagatsel 300m, October

Description

Torenia violacea is a small annual herb widely distributed across tropical and subtropical Asia, recorded by GBIF, with over a thousand occurrences, from India, Nepal, Bhutan and Bangladesh through China, Taiwan and Japan to Myanmar, Thailand, Laos, Cambodia, Vietnam, the Philippines, Malaysia, Singapore, Brunei, Indonesia and Papua New Guinea. It is a plant of warm, humid lowland and lower montane situations, growing on moist, shaded ground in rice-field margins, ditches, streamsides, damp roadside banks, forest paths and other disturbed wet places, mostly at low elevations. The photographed plant from Pemagatsel in southeastern Bhutan, at about 300 m and flowering in October, exemplifies this low-altitude, monsoon-influenced habitat, where the species flowers into the post-monsoon autumn in the warm foothill zone.

It is a slender, erect to ascending or somewhat decumbent annual with quadrangular, narrowly winged stems that branch from the base. The leaves are opposite, ovate to ovate-lanceolate, with a serrate margin, an acute apex and a rounded to broadly cuneate base, borne on short petioles. The flowers are axillary or in terminal racemes, each subtended by a tubular, five-winged (ridged) calyx. The corolla is two-lipped and violet to pale lilac, often with a yellow throat, the lower lip three-lobed and the tube curved; the four didynamous stamens are a diagnostic feature, the anterior filaments often bearing a slender appendage at the base. The fruit is a narrow, oblong, septicidal capsule enclosed by the persistent winged calyx and releasing numerous minute seeds.

Long placed in Scrophulariaceae and later in Veronicaceae or Plantaginaceae, Torenia is now assigned to the segregate family Linderniaceae, recognised on molecular grounds, alongside Lindernia and Vandellia, to which several species formerly called Torenia have been transferred. T. violacea, based on Azaola's name and recombined by Pennell, is distinguished within the genus by its five-winged calyx and violet corolla. The species is a self-compatible weedy annual of disturbed wet ground, abundant and adaptable across its very large range, and is of no conservation concern; ornamental relatives in the genus (the "wishbone flowers") are popular bedding plants.

Author: (Azaola) Pennell · Sources: POWO (Kew), GBIF, Flora of China Vol. 18, Flora of Bhutan Vol. 2, Flora of Nepal, Flora of Pakistan, Fischer's revision of Linderniaceae

Anacardiaceae

Toxicodendron hookeri

by GP Jürgens

(K.C.Sahni & Bahadur) C.Y.Wu & T.L.Ming

Bhutan2015 212
Bhutan Zhemgang 1000m, October

Description

Toxicodendron hookeri is a Himalayan and southwest Chinese sumac distributed through Nepal, the Indian Himalaya, Bhutan, southern China and into Thailand, with about 104 GBIF occurrences. It is a tree of warm subtropical and lower temperate broadleaved forest, growing along forest margins, on open slopes, in secondary woodland and in ravines on well-drained soils. The plant photographed at Zhemgang in central Bhutan at about 1000 m in October is representative of its preferred lower-montane belt of roughly 800-2500 m, where the autumn collection captures the foliage as it turns brilliant red, the leaves reddening before they fall.

It is a deciduous shrub or small to medium tree with greyish bark and stout, glabrescent twigs exuding an irritant resinous sap. The leaves are alternate and pinnately compound with several pairs of opposite, ovate to oblong-lanceolate, entire leaflets and a terminal one, the rachis sometimes narrowly winged, the whole turning vivid scarlet in autumn. The small, greenish-yellow, functionally unisexual flowers are borne in axillary panicles, with a five-parted calyx and corolla and a single-loculed ovary. The fruit is a small, dry, somewhat compressed drupe with a hard endocarp, ripening pale and persisting on the bare branches.

The plant's legacy link refers to it under the name Rhus succedanea, reflecting the former placement of these taxa in a broad Rhus; modern treatments segregate the lacquer-sap species into Toxicodendron, of which T. hookeri is one. As in poison ivy and the lacquer tree, the sap contains urushiol-type alkylcatechols that cause severe contact dermatitis. The species belongs to the resin-yielding, wax-producing group long valued in eastern Asia, and its bright autumnal colour makes it conspicuous in the Himalayan forest.

Author: (K.C.Sahni & Bahadur) C.Y.Wu & T.L.Ming · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Min & Barfod Anacardiaceae account, Gillis revision of Toxicodendron

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 elongata 

by G & P Jürgens

DC.

Garw 2005 274 ergebnis
India Garhwal Kunol 2550m, September

Description

Tricholepis elongata is a thistle-like composite of the Himalaya and adjacent regions, with roughly 120 GBIF occurrences recorded chiefly from India, Nepal and Pakistan. It is a plant of warm to cool temperate slopes, favouring open, sunny, often dry and somewhat rocky or grassy ground, scrub margins, banks and disturbed sites in the montane zone. The specimen photographed at Kunol in Garhwal, India, at about 2550 m in September was recorded toward the close of the monsoon, the late-summer to autumn flowering period when many montane thistle relatives in this elevational band come into bloom.

It is an erect, branched perennial or biennial herb, the stems slender and elongate as the epithet suggests, bearing alternate leaves that are linear to lanceolate, entire to toothed or somewhat divided, and frequently roughened. The capitula are solitary or few at the branch tips and are homogamous, composed wholly of slender tubular disc florets, pink to purple in colour. The involucral bracts (phyllaries) are numerous, narrow and tapering, often with finely fringed or hair-tipped margins, a feature reflected in the generic name. The fruit is a small cypsela crowned by a pappus of fine bristles or scales that promotes wind dispersal.

Tricholepis belongs to tribe Cardueae, the thistle tribe, and is distinguished by its finely dissected or ciliate phyllary appendages and bristly pappus. The genus is centred on the Indian subcontinent and the Himalaya. As a species of open and frequently disturbed montane habitats, T. elongata is not of conservation concern; such thistle-relatives provide nectar and pollen to a range of insect pollinators and contribute to the herbaceous flora of dry temperate slopes.

Author: DC. · Sources: POWO (Kew), GBIF, Flora of Pakistan, Hooker Flora of British India, Flora of Nepal, Susanna & Garcia-Jacas Cardueae systematics

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)

Cucurbitaceae

Trichosanthes costata

by G & P Jürgens

Blume

Bhutan2015 160
Bhutan, Zhemgang 910m, October

Description

Trichosanthes costata Blume is a climbing cucurbit widely distributed across tropical and subtropical Asia, recorded by GBIF from China, Indonesia, Thailand, Taiwan, India, Malaysia, Vietnam, Cambodia, the Philippines, Myanmar, Laos and Bhutan, with over 600 occurrences. It grows in lowland to lower montane forest, secondary growth and thickets, scrambling over shrubs by tendrils. The Bhutanese material from Zhemgang at 910 m in October reflects its preference for the warm subtropical foothills and its autumn fruiting, when the ribbed fruits that give the epithet mature.

It is a slender, herbaceous to somewhat woody climbing vine with angular or ribbed stems and axillary tendrils. The leaves are alternate, broadly ovate to suborbicular, often three- to five-lobed, cordate at the base, with a dentate margin and palmate venation. The plants are monoecious or dioecious, the white flowers with the fringed corolla lobes characteristic of Trichosanthes, the males in racemes and the solitary females with an inferior ovary. The fruit is a small ellipsoid berry, conspicuously ribbed or costate, ripening red to orange, with several compressed seeds dispersed by frugivores.

Trichosanthes costata, sometimes treated under the segregate name Gymnopetalum but here accepted in the broader Trichosanthes, belongs to a large Old World genus of forest lianas distinguished by their fringed corollas, thought to attract nocturnal hawkmoth pollinators. Its wide Indo-Malesian to Sino-Himalayan range and tolerance of disturbance make it common in secondary forest, and several relatives are economically or medicinally important. It is not considered threatened, reflecting its colonising habit.

Author: Blume · Sources: POWO (Kew), GBIF, Flora of China Vol. 19, Flora of Bhutan Vol. 2, Flora of Nepal, de Wilde & Duyfjes revisions of Asian Cucurbitaceae (Trichosanthes)