Tag:

Subtropical (<1500 m)

Malvaceae

Urena lobata

by GP Jürgens

L.

Bhutan2012 458
Bhutan Zhemgang 1200m, October

Description

Urena lobata is a pantropical subshrub of remarkably wide distribution, with GBIF recording over 31000 occurrences spanning the Americas, Africa, Asia and Australasia, including the United States, Brazil, China, Australia, India, Indonesia, Madagascar, the Philippines and many other countries. A vigorous colonist of open, disturbed and seasonally moist ground, it grows along roadsides, in waste places, fallow fields, forest margins and grassland, mostly at low to middle elevations. The plant photographed at Zhemgang in southern Bhutan at about 1200 m, in October, occupies the warm subtropical foothill habitat where it is a common weed of cleared and cultivated land.

The plant is an erect, woody-based perennial herb or subshrub clothed throughout in stellate, often stinging-rough hairs. The leaves are alternate, variable, the lower ones rounded and shallowly three- to five-lobed or angled, the upper narrower, with toothed margins and conspicuous nectaries on the principal veins beneath. The flowers are solitary or clustered in the leaf axils, with an epicalyx of five bracteoles, five free pink to rose petals, and the stamens united into a staminal column typical of the Malvaceae. The fruit is a depressed schizocarp splitting into five indehiscent mericarps, each densely covered in glochidiate (hooked) spines that cling to fur and clothing, ensuring epizoochorous dispersal.

Urena lobata is economically significant as a bast-fibre plant, cultivated and gathered as "Congo jute" or "aramina", and the hooked fruits make it both an effective long-distance disperser and an aggressive weed in many warm regions, where it is sometimes regarded as invasive. Its enormous global range and tolerance of disturbance place it well outside any conservation concern. The species exemplifies a successful pantropical weed whose burr-like fruits have carried it, often with human aid, across the tropics and subtropics of both hemispheres.

Author: L. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Flora of Tropical East Africa (Malvaceae), Borssum Waalkes revision of Malesian Malvaceae

Apocynaceae

Vallaris solanacea

by GP Jürgens

(Roth) Kuntze

Bhutan2014 231 1
Bhutan Karu-Chu 1800m, May
Bhutan2014 234
Bhutan Karu-Chu 1800m, May
Nepal 97 28 P45
Nepal Dhoban 735m April

Description

Vallaris solanacea is a woody climber of tropical and subtropical Asia, broadly distributed from the Indian subcontinent and the Himalayan foothills through Indochina, southern China and the Malesian region (gbif_countries: IN, TH, CN, NP, MM, US, ZZ, LK, MY, GP, KH, LA, BD, BT, VN, ID, PK, SC), with GBIF documenting some 536 occurrences. It grows in lowland and submontane forests, thickets, riverine scrub and forest margins, often scrambling over shrubs and small trees. The illustrated gatherings range from Dhoban in Nepal at about 735 m, flowering in April, up to Karu-Chu in Bhutan near 1800 m in May, reflecting its preference for warm, humid lower hill country.

The plant is a glabrous to finely pubescent liana with milky latex and opposite, elliptic to ovate leaves that are entire, pinnately veined and shortly petiolate. The flowers are borne in axillary or terminal cymes and are fragrant, with a white, rotate to broadly campanulate corolla bearing five spreading lobes, the throat marked with hairy appendages; the floral form recalls a Solanum, the resemblance enshrined in the epithet. The androecium consists of five stamens with connivent anthers adhering to the stigmatic head, and the fruit is a pair of slender, spreading follicles releasing comose seeds adapted to wind dispersal.

A member of subfamily Apocynoideae, Vallaris is a small Indomalayan genus of latex-bearing twiners. V. solanacea is locally valued as an ornamental for its sweetly scented blossoms and is used in traditional medicine, while its latex and tissues, like those of many Apocynaceae, contain bioactive compounds. Widespread and adaptable, it is of no conservation concern across its extensive range.

Author: (Roth) Kuntze · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of China, Flora of British India, Flora Malesiana account of Apocynaceae

Orchideaceae

Vanda griffithii

by GP Jürgens

Lindl.

Bhutan2014 269
Bhutan Trithangebe near a farmhouse 700m, May

Description

Vanda griffithii is an epiphytic orchid of the eastern Himalaya, documented in GBIF from Bhutan, India and Nepal across a modest 19 occurrences, reflecting both its localised distribution and the under-collection of canopy epiphytes. It inhabits warm to cool broad-leaved forest, growing on tree trunks and branches at low to mid elevations, roughly 700-1800 m. The photographed plant was recorded in Bhutan at Trithangebe, perched near a farmhouse at about 700 m in May, illustrating its tolerance of disturbed and semi-cultivated settings where suitable phorophytes persist.

It is a monopodial epiphyte with a short to elongate stem clothed in distichous, ligulate, leathery leaves that are channelled and obliquely praemorse (toothed) at the apex, with stout aerial roots anchoring the plant. The inflorescence is a short axillary raceme of a few fleshy, long-lived flowers; the sepals and petals are subequal, spreading, typically greenish-yellow to brownish and often barred or tessellated, while the small three-lobed labellum bears a saccate or shortly spurred base characteristic of the genus. The column is short and footless, with a beaked anther cap and waxy pollinia, and fertilised flowers develop into an elongate, ribbed capsule releasing dust-like seeds.

Vanda (Orchidaceae, subtribe Aeridinae) is a horticulturally celebrated genus of monopodial epiphytes, and like all orchids it is listed on CITES Appendix II, regulating international trade. Reproduction depends on specific pollinators and mycorrhizal fungi for seed germination. Its narrow Himalayan range and reliance on intact forest canopy render it vulnerable to deforestation and over-collection for the ornamental trade.

Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of Bhutan, The Orchids of Bhutan, CITES Appendix II listing, Genera Orchidacearum

Rubiaceae

Wendlandia heynei

by GP Jürgens

(Schult.) Santapau & Merchant

Nepal 97 42 P62
Nepal Mewa-Khola 1050m April
Nepal 97 43 P63
Nepal Mewa-Khola 1050m April
Sikkim 2006 273 ergebnis
India West-Bengal, Lingza 1300m, May

Description

Wendlandia heynei is a shrub or small tree of the Indian subcontinent and its Himalayan foothills, recorded from India, Nepal, Bhutan and Pakistan. GBIF holds some 179 occurrences, the bulk across peninsular and north-eastern India and the lower Himalaya. It is a plant of warm-temperate to subtropical broad-leaved forest, forest margins, ravines and secondary scrub on hill slopes, typically from the plains up to roughly 1500 m. The populations imaged in eastern Nepal at Mewa-Khola (1050 m, April) and in the Darjeeling region of Indian West Bengal at Lingza (1300 m, May) illustrate its place in the moist hill forests of the eastern Himalayan tract, flowering as the pre-monsoon season advances.

The plant is evergreen to semi-deciduous, with terete, often puberulous young branchlets. The leaves are opposite or sometimes ternate, elliptic to oblong-lanceolate, entire and acuminate, with interpetiolar stipules typical of the Rubiaceae. The small flowers are crowded in large, much-branched terminal panicles or thyrses that give the tree a frothy, plumose appearance. Each flower has a short-lobed calyx, a white, funnel- to salver-shaped corolla with a slender tube and five spreading lobes, and five included or shortly exserted stamens; the ovary is inferior and bilocular. The fruit is a minute, globose, septicidal capsule containing numerous small angular seeds.

Wendlandia (tribe Wendlandieae) is a genus of around ninety species centred on tropical and subtropical Asia, distinguished by its dense paniculate inflorescences and small capsular fruits. The epithet honours Heyne, and the species has accumulated several synonyms reflecting its wide variability across the subcontinent. As a common, adaptable component of disturbed and secondary hill forest it is not of conservation concern; locally its wood and bark have minor uses.

Author: (Schult.) Santapau & Merchant · Sources: POWO (Kew), GBIF, Flora of British India, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, revision of the genus Wendlandia (Cowan)

Lythraceae

Woodfordia fruticosa

by GP Jürgens

Kurz

Bhutan2014 147
Bhutan Trashigang 1470m, May
Nepal 2001 461 ergebnis ergebnis
Nepal (Gorkha) Gunda 1700m, May

Description

Woodfordia fruticosa is a widespread Old World shrub ranging from the Indian subcontinent through China and Southeast Asia to Madagascar and tropical Africa, with GBIF documenting around 1657 occurrences across India, China, Madagascar, Nepal, Indonesia, Sri Lanka, Myanmar, Pakistan, Bhutan, Bangladesh and Thailand. It is a plant of warm, seasonally dry habitats, characteristically colonising open hill slopes, rocky outcrops, scrub, forest margins and disturbed ground from the lowlands into the lower hills. The plants recorded at Trashigang in Bhutan at about 1470 m and at Gunda in Gorkha, Nepal at about 1700 m, both in May, illustrate its presence in the subtropical mid-hill zone, where it flushes with bright flowers at the onset of the warm season.

It is a much-branched deciduous shrub with long, often arching or pendulous branches and grey-brown bark. The leaves are opposite or subopposite, sessile to subsessile, lanceolate to oblong-lanceolate, entire-margined, dull green above and densely whitish- or rusty-tomentose and gland-dotted beneath. The flowers are clustered in short axillary cymes and are conspicuously bright red to orange-red; each has a tubular, slightly curved, ribbed calyx (hypanthium) with short triangular lobes, minute or vestigial petals, and numerous long-exserted stamens, giving the inflorescence a brush-like appearance. The fruit is a small ellipsoid capsule enclosed within the persistent calyx tube, releasing numerous tiny seeds.

The tubular red flowers and copious nectar of W. fruticosa make it strongly ornithophilous, attracting sunbirds and other nectar-feeding birds that act as pollinators, while it is also valued by beekeepers. Dried flowers (known as dhataki) are widely used in traditional medicine and notably as a natural fermentation agent in Ayurvedic preparations, owing to abundant tannins and polyphenols. The sole or near-sole member of its genus, the species is robust, fast-colonising and locally abundant, and is not of conservation concern.

Author: Kurz · Sources: POWO (Kew), GBIF, Flora of China Vol. 13, Flora of Bhutan Vol. 2, Flora of Nepal, Graham Revision of the Lythraceae of the Indian Subcontinent

Apocynaceae

Wrightia arborea

by GP Jürgens

(Dennst.) Mabb.

Bhutan2014 261
Bhutan Trithangebe 700m, May
Nepal 97 564 P1097
Nepal Sabha-Khola 550m May

Description

Wrightia arborea is a small deciduous tree of the Indian subcontinent and Southeast Asia, distributed across India, Thailand, China, Sri Lanka, Myanmar, Nepal, Bhutan and much of the surrounding region, with about 709 georeferenced occurrences in GBIF. It grows in dry to moist deciduous forest, woodland and scrub, mainly in the warm subtropical lowlands and foothills. The trees illustrated were photographed at Trithangebe in Bhutan (700 m) and along the Sabha-Khola in Nepal (550 m) in May; across its range it typically occurs below about 1200 m on a variety of well-drained soils.

The species is a small tree exuding milky latex, with opposite, simple, elliptic to ovate leaves that are softly hairy, acuminate and pinnately veined. The flowers are borne in terminal cymes and are showy and fragrant, with a salverform white to creamy or pale yellow corolla ageing to pink or dull orange; a conspicuous fringed corona of scales surrounds the throat, a diagnostic feature of the genus. The fruit consists of two slender, elongate follicles that are united or cohering at the tip and split to release numerous flattened seeds, each bearing an apical tuft of silky hairs (coma) for wind dispersal.

Wrightia (Apocynaceae, subfamily Apocynoideae) is a genus of latex-bearing trees and shrubs notable for the ornate coronal scales of its flowers. W. arborea yields a fine, close-grained pale wood traditionally prized for carving and turnery, and various parts have been used in folk medicine and as a source of dye. Adaptable and widely distributed, the species is common across its range and is not considered to be of conservation concern, though local populations depend on the persistence of deciduous forest and woodland habitat.

Author: (Dennst.) Mabb. · Sources: POWO (Kew), GBIF, Flora of China, Flora of British India, Flora of Bhutan, Ngan Revision of the Genus Wrightia

Amaryllidaceae

Zephyranthes candida

by G & P Jürgens

(Lindl.) Herb.

Bhutan2012 1104
Bhutan Khoma 950m, October

Description

Zephyranthes candida is native to the marshlands and riverbanks of the Río de la Plata region in Argentina and Uruguay, but has become one of the most widely naturalised bulbous plants in tropical and subtropical Asia, Africa, and Oceania. GBIF documents over 2,810 occurrences spanning more than 20 countries, with substantial records from the United States, Japan, India, China, and Australia. In the eastern Himalayas, it occurs as a naturalised garden escape in warm valleys and lowland settlements at elevations below 1,500 m. At Khoma in eastern Bhutan at 950 m, it grows along roadsides, field margins, and around homesteads, flowering abundantly in October during the late monsoon and post-monsoon period.
Zephyranthes candida is a bulbous perennial herb. The bulb is ovoid, 2–3 cm in diameter, with a dark brown tunic. Leaves are basal, linear, rushlike, 15–30 cm long and 2–4 mm wide, dark green, semi-erect, and persistent through much of the year. The scape is slender, hollow, 15–25 cm tall, bearing a single erect flower subtended by a tubular spathe. The flower is actinomorphic, crocus-like, 3–5 cm across, with six white tepals that are broadly elliptic and slightly tinged green at the base externally. Stamens are six, subequal, with yellow anthers. The ovary is inferior, trilocular; the fruit is a depressed-globose capsule containing flattened black seeds.
Despite its alien origin, Zephyranthes candida has become thoroughly established across warm regions of the Himalayan foothills and is now a familiar element of the naturalised flora of Bhutan, Nepal, and northeast India. Its rapid vegetative spread via daughter bulbs, tolerance of a wide range of soil moisture conditions, and prolific seed production contribute to its success as a coloniser of disturbed habitats. The species is taxonomically placed in Zephyranthes sensu lato; some recent molecular treatments have subsumed it within an expanded Habranthus, though most regional Floras retain the traditional placement.

Author: (Lindl.) Herb. · Sources: POWO (Kew), GBIF, Flora of China Vol. 24, Flora of Bhutan Vol. 3, Meerow & Snijman: Amaryllidaceae in Kubitzki: Families and Genera of Vascular Plants Vol. 3 (1998)

Amaryllidaceae

Zephyranthes carinata

by GP Jürgens

Herb.

Nepal 1994 323 ergebnis
Ost-Nepal Chainpur 1300m May 
Nepal 2001 60 ergebnis ergebnis
East-Nepal Mulkharka 1920m, April

Description

Zephyranthes carinata, the rosepink rain lily, is native to Mexico and Central America but is now pantropically naturalised, GBIF recording some 1370 occurrences across the Americas, southern Africa, South and East Asia and Australasia. In the Himalaya it is a widespread garden escape, recorded across Nepal and northern India where it colonises grassy banks, roadsides, lawns and disturbed moist ground at low to middle elevations. The eastern Nepalese populations at Chainpur (1300 m, May) and Mulkharka (1920 m, April) show its spread into hill cultivation, where it flowers gregariously after the first rains.

It is a small bulbous geophyte with a tunicated, ovoid bulb bearing a few narrowly linear, somewhat keeled basal leaves (the epithet carinata referring to the carinate blade). The solitary flowers are borne on a hollow scape, each subtended by a tubular spathaceous bract. The perianth is funnel-shaped and erect, rose-pink to rose-purple fading paler, of six subequal tepals fused below into a short tube; within are six stamens in two series and an inferior trilocular ovary with a slender, shortly trifid style. The fruit is a depressed-globose loculicidal capsule with numerous flattened black seeds, though much spread is clonal through bulb offsets.

Zephyranthes belongs to tribe Hippeastreae of Amaryllidaceae, characterised by solitary, scapose, rain-triggered flowers. Z. carinata has long been confused with Z. grandiflora, the names variously applied in horticulture; current treatments accept Z. carinata as correct for the common pink rain lily. A hardy, free-flowering ornamental of no conservation concern, its readiness to naturalise makes it a minor weed of lawns and grasslands across its adopted Asian range.

Author: Herb. · Sources: POWO (Kew), GBIF, Flora of China Vol. 24, Flora of Pakistan, Annotated Checklist of the Flowering Plants of Nepal, Meerow and Snijman revision of Amaryllidaceae genera

Orchideaceae

Zeuxine goodyeroides

by GP Jürgens

Lindl.

Bhutan2012 1024
Bhutan Trithangebe 900m, October
Bhutan2012 1025
Bhutan Trithangebe 900m, October

Description

Zeuxine goodyeroides is a terrestrial orchid of shaded forest floors in the eastern Himalaya and adjoining mountains of China (including Yunnan and Tibet), India, Nepal, Bhutan, Myanmar and Sri Lanka, with around 56 documented occurrences indicating a scattered but wide distribution. It grows in leaf litter and humus-rich soils of subtropical to lower-temperate broad-leaved and mixed forest, generally between about 800 and 2000 m. The photographed plant was recorded at Trithangebe in Bhutan at 900 m, flowering in October, when the post-monsoon humidity favours the development of these inconspicuous ground orchids.

The species is a small herb arising from a creeping, fleshy rhizome that roots at the nodes, the erect stem bearing several spirally arranged leaves toward the base. The leaves are ovate-lanceolate, somewhat fleshy, often with a pale midrib, recalling the genus Goodyera to which the epithet alludes. The inflorescence is a slender, pubescent terminal raceme of numerous small, non-resupinate-appearing white to greenish flowers; the sepals are pubescent dorsally, the petals adhere to the dorsal sepal forming a hood, and the diagnostic labellum is saccate at the base with two basal glands and bears a transversely dilated, bilobed epichile. The fruit is a small dehiscent capsule with dust-like seeds.

Zeuxine belongs to subtribe Goodyerinae of the Orchidaceae (here spelled Orchideaceae as supplied), the jewel-orchid alliance, distinguished by the spurless, basally pouched labellum bearing internal glands. Easily overlooked owing to its small stature, it depends like most terrestrial Goodyerinae on mycorrhizal associations in undisturbed forest humus. It is not formally assessed but is sensitive to forest-floor disturbance.

Author: Lindl. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, The Genera Orchidacearum (Pridgeon et al.)