Author

GP Jürgens

Lamiaceae

Stachys melissifolia

by GP Jürgens

Benth.

BhutanPG2011 841
Bhutan Paro-Chu, 2400m July
Nepal 99 587 ergebnis
West-Nepal Garpung-Khola 3300m, July

Description

Stachys melissifolia is a perennial mint-family herb of the Himalaya and adjacent mountains, recorded from Nepal, China, India, Bhutan and Pakistan, with around 146 occurrences in GBIF; under its current treatment the name is accepted for the Himalayan plant. It occupies forest margins, moist shaded banks, shrubberies and grassy slopes of the temperate and lower subalpine belt, broadly between 2000 and 3500 m. The photographs from the Paro Chu in Bhutan at about 2400 m and from the Garpung Khola in West Nepal at about 3300 m, both in July, show the species in flower during the summer monsoon in its typical mid-montane woodland-edge habitat.

The plant is an erect to ascending perennial with the quadrangular stems characteristic of the Lamiaceae, usually softly hairy. The leaves are opposite, ovate to oblong with a cordate to rounded base, crenate-serrate margins and a rugose, wrinkled surface, somewhat resembling those of balm (Melissa), as the epithet melissifolia denotes. The flowers are borne in distinct whorls (verticillasters) forming an interrupted terminal spike; the calyx is tubular-campanulate with five subequal teeth, and the bilabiate corolla is pinkish to purple with a short, erect upper lip and a spreading three-lobed lower lip. The fruit comprises four small ovoid nutlets enclosed in the persistent calyx.

Stachys is a large, cosmopolitan genus of the Lamiaceae subfamily Lamioideae, and its Himalayan members have been subject to repeated nomenclatural revision, several names having passed in and out of synonymy. The verticillate inflorescence and bilabiate corolla are adapted to pollination by bees and other long-tongued insects. Widely distributed through the temperate Himalaya, S. melissifolia is common and of no conservation concern.

Author: Benth. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Harley et al. Labiatae in The Families and Genera of Vascular Plants

Stachyuraceae

Stachyurus himalaicus

by GP Jürgens

Hook.f. & Thomson ex. Benth.

Bh2008 17 P30
Bhutan Thimphu-Chu, 2800m April
Nepal 97 125 G217
Nepal Mewa-Khola 2470m April

Description

Stachyurus himalaicus is a Sino-Himalayan shrub distributed from Nepal and northern India through Bhutan, northern Myanmar and southern China to Taiwan, with around 4100 GBIF occurrences and a peripheral introduced presence in Japan, Korea and cultivation in Belgium. It grows in moist broad-leaved and mixed evergreen forest, along streamsides, forest margins and shrubby slopes in the warm-temperate to lower cool-temperate belt, roughly 1500 to 3000 m. The plants recorded along the Thimphu-Chu in Bhutan at 2800 m and at Mewa-Khola in Nepal at 2470 m, both flowering in April before leaf expansion, exemplify its precocious early-spring display on humid montane slopes.

It is a deciduous shrub or small tree with reddish-brown, glabrous, lenticellate branchlets. The leaves are alternate, ovate-lanceolate to oblong, acuminate, with serrate to serrulate margins and a slender petiole, the young foliage sometimes flushed reddish. Its diagnostic feature is the inflorescence: stiff, pendent, spike-like racemes produced from the leafless nodes, each bearing numerous small, shortly pedicellate, bell-shaped pale yellow flowers with four sepals, four petals and eight stamens. The superior ovary develops into a small, globose, leathery to fleshy berry containing many minute seeds embedded in pulp.

Stachyurus is the sole genus of the small family Stachyuraceae, an isolated lineage within the Crossosomatales, and S. himalaicus is its principal Himalayan representative, distinguished from the Chinese S. chinensis by leaf and inflorescence characters. The pre-foliar flowering exploits an open canopy and attracts early-season bees, while the berries are bird-dispersed. The species is common and not of conservation concern.

Author: Hook.f. & Thomson ex. Benth. · Sources: POWO (Kew), GBIF, Flora of China Vol. 13, Flora of Bhutan Vol. 2, Flora of Nepal, A Revision of the Genus Stachyurus (Stachyuraceae)

Caryophyllaceae

Stellaria vestita

by GP Jürgens

Kurz

Bhutan2014 1072
Bhutan Paro 2400m, May

Description

Stellaria vestita is a widespread chickweed of tropical and subtropical Asia, ranging from the Himalaya through southern China and Taiwan to Indochina, the Malesian archipelago, the Philippines and New Guinea, and eastward to Japan and Korea; GBIF records over 2,000 occurrences. It grows in open forest, scrub, grassy slopes, hedgerows and disturbed ground, generally from low elevations to about 2,800 m. The individual photographed near Paro in western Bhutan at 2,400 m in May reflects its presence in the temperate mid-montane belt of the eastern Himalaya, on moist, partially shaded banks and forest margins.

It is a perennial herb with weak, ascending to straggling stems 30-90 cm long, terete and densely clothed throughout with spreading white hairs, hence the epithet vestita ('clothed'). The leaves are opposite, sessile or shortly petiolate, ovate to ovate-lanceolate, 1-4 cm long, acuminate and pubescent on both surfaces. The inflorescence is a lax, dichasial cyme of several flowers on slender pedicels. Each flower has five lanceolate, pubescent sepals and five white petals deeply cleft nearly to the base into two lobes, the petals about equalling the calyx; there are typically ten stamens and three styles. The fruit is an ovoid capsule dehiscing by six valves and containing several reniform, tuberculate seeds.

Within the large and taxonomically complex genus Stellaria, S. vestita is recognised by its dense indumentum, deeply bifid petals and pantropical Asian distribution, features separating it from the S. media group and from glabrous montane species. The deeply two-lobed white petals are typical of the genus and aid pollination by small insects, while the many-seeded capsules favour effective local dispersal. As a common, weedy and ecologically tolerant species occupying a wide range of habitats and elevations, it is of least concern and faces no recognised conservation threat.

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

Thymelaeaceae

Stellera chamaejasme

by GP Jürgens

L.

Nepal 1989 65
Nepal Bhatang 2915m, April
Nepal 99 362 ergebnis
West-Nepal Kalomura 3600m, June

Description

Stellera chamaejasme is a widespread perennial herb of the dry uplands of Central and East Asia, recorded by GBIF from China, Russia, Mongolia, Nepal, India, Bhutan, Kazakhstan, Korea, Iran and Turkey, among others, across some 3,400 georeferenced occurrences. It is characteristic of arid and semi-arid grasslands, alpine and subalpine meadows, sunny rocky slopes and overgrazed pastures on the Tibetan Plateau and throughout the trans-Himalaya, generally between about 2,600 and 4,500 m. The cited Nepalese records, from Bhatang at 2,915 m in April and from Kalomura in West Nepal at 3,600 m in June, span its lower temperate and upper subalpine occurrences and bracket its long spring-to-summer flowering season. It thrives on poor, dry soils where grazing has reduced competing vegetation.

The plant grows from a thick, woody, deep-seated taproot and rootstock, producing numerous erect, slender, unbranched leafy stems in a dense tuft. The leaves are numerous, alternate, crowded, narrowly lanceolate to elliptic, sessile and entire. The flowers are borne in a dense terminal capitate head; each flower lacks petals but has a showy, petaloid, tubular calyx whose five spreading lobes are commonly white above and flushed rose-red to purplish in bud on the outside, producing a striking bicoloured head. There are typically ten stamens in two whorls within the calyx tube, and the fruit is a small dry achene-like nutlet enclosed in the persistent base of the perianth.

Stellera chamaejasme is the best-known species of its genus within Thymelaeaceae and is notorious as a toxic, unpalatable indicator of rangeland degradation; its expansion is regarded across Tibet and Mongolia as a sign of overgrazing, since livestock avoid the poisonous foliage and roots. The plant is rich in bioactive diterpenoids and lignans and has a long history in Tibetan and Chinese traditional medicine, while its tough bast fibres have been used in papermaking. Though abundant and in no way threatened, it is ecologically significant as both a grassland weed and a chemically defended species of considerable pharmacological interest.

Author: L. · Sources: POWO (Kew), GBIF, Flora of China Vol. 13, Flora of Bhutan Vol. 2, Flora of Nepal, Flora of Pakistan, Tan & Wang: revision of Asian Thymelaeaceae and the Stellera complex

Asteraceae

Stenoseris graciliflora

by GP Jürgens

(Wall. ex DC.) C.Shih

Bhutan2012 428
Bhutan Wangdi 3300m, June

Description

Stenoseris graciliflora is a slender herbaceous composite of the temperate to subalpine Himalaya, ranging through China, India, Nepal, Myanmar and Bhutan, with 160 GBIF records tracing its distribution along the moist montane forest belt and adjoining clearings. It typically grows in forest margins, shrubberies and grassy openings on humus-rich soils between roughly 2500 and 3800 m. The illustrated plant was collected near Wangdi in western Bhutan at about 3300 m in June, in the upper temperate zone where the monsoon supports a tall-herb flora amid fir and rhododendron forest.

In GBIF the name is treated as a synonym, with Stenoseris graciliflora maintained as the accepted name for this entity. The plant is an erect perennial with slender, often leafy and branching stems exuding milky latex when broken, as is typical of the lettuce tribe. The leaves are thin, the lower ones often lyrate-pinnatifid and narrowing to a winged petiole, the upper smaller and clasping. The inflorescence is a lax, narrow panicle of small, few-flowered capitula, each enclosed by a cylindrical involucre of imbricate phyllaries; the florets are all ligulate and pale blue to lilac. The fruit is a flattened, ribbed cypsela bearing a soft white pappus of fine bristles.

Stenoseris is a small genus of the tribe Cichorieae (Lactuceae), segregated from Cicerbita and Lactuca on the basis of its slender capitula, achene morphology and pappus characters. The basionym authority (Wall. ex DC.) C.Shih reflects the species' long taxonomic passage among these closely allied genera. As a widespread montane herb it is not regarded as threatened, though it serves as a useful indicator of intact, humid temperate forest understorey.

Author: (Wall. ex DC.) C.Shih · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Compositae of the Himalaya (Cichorieae monographs)

Malvaceae

Sterculia lanceolata var. coccinea

by GP Jürgens

(Jack) Phengklai

Bhutan2015 230
Bhutan Zhemgang 950m, October

Description

Sterculia lanceolata var. coccinea is a tree of tropical and subtropical Asia, ranging from the Indian subcontinent (India, Nepal, Sri Lanka) through Myanmar, Thailand, Indochina (Vietnam, Laos, Cambodia) and southern China into Malesia (Malaysia, Indonesia, Singapore, Brunei, Philippines), as reflected in the 322 GBIF records. It occurs in evergreen and semi-evergreen lowland to lower-montane forest, along streams and forest margins, typically below about 1500 m. The photographed tree from Zhemgang in central Bhutan at around 950 m, fruiting in October, sits at the warm-temperate northern edge of the species' range, where the bright fruiting display is conspicuous in autumn.

The variety is a small to medium tree with a slender bole and spreading crown. The leaves are alternate, simple, elliptic-lanceolate to oblong, entire, glabrescent and pinnately veined, on slender petioles — the lanceolate blade distinguishing this species from the palmately lobed S. villosa. The small flowers are apetalous with a campanulate, lobed calyx and are borne in axillary panicles; the variety coccinea is named for its scarlet colouring. The fruit is the diagnostic cluster of woody, beaked follicles that ripen a vivid red ('coccineus') and split open to reveal glossy black seeds against the crimson inner wall.

Now classified in Malvaceae subfamily Sterculioideae (formerly Sterculiaceae), Sterculia lanceolata is a variable species, and this variety, based on the basionym described by Jack and recombined by Phengklai, segregates the scarlet-fruited Malesian-Indochinese populations. The boldly coloured dehisced follicles are bird-dispersed, the contrasting red and black serving as a visual lure. Widespread and occurring in both primary and secondary forest, the taxon is not regarded as threatened.

Author: (Jack) Phengklai · Sources: POWO (Kew), GBIF, Flora of Thailand, Flora of China, Flora of British India, Kostermans Sterculiaceae monograph

Malvaceae

Sterculia villosa

by GP Jürgens

Roxb.

Bhutan2014 253
Bhutan Karu-Chu 1800m, May
Bhutan2014 264
Bhutan Karu-Chu 1800m, May

Description

Sterculia villosa is a deciduous tree widely distributed across tropical and subtropical Asia, from India, Nepal, Bangladesh, Bhutan and Sri Lanka eastward through Myanmar, Thailand, Vietnam, southern China and into Malesia (Malaysia, Indonesia), with the 452 GBIF records reflecting both this native range and cultivated or naturalised occurrences elsewhere. It is a tree of monsoon and deciduous forest, riverine valleys and disturbed slopes at low to moderate elevations, generally below about 1500 m though reaching higher in warm valleys. The photographed individual from the Karu-Chu valley in Bhutan at around 1800 m, flowering in May before or with the new leaves, marks the upper, warm-temperate edge of its range.

The tree has a straight bole, grey bark and stout branches, the young parts densely clad in soft tawny villous hairs from which the epithet derives. The large, alternate leaves are palmately lobed with 5-7 broad lobes, cordate at the base and long-petioled, hairy beneath. The flowers, borne in much-branched velvety panicles, are apetalous, with a campanulate, lobed, reddish to greenish-yellow calyx; the species is andromonoecious with a central androgynophore. The fruit is the characteristic sterculiaceous group of large, woody, beaked, velvety follicles that dehisce to expose black seeds against a red interior.

Formerly placed in Sterculiaceae, the genus Sterculia is now treated within an enlarged Malvaceae (subfamily Sterculioideae), as adopted here. S. villosa is economically valued for its strong bast fibre, used for ropes and cordage, and yields a gum; its bark and seeds feature in local medicine. As a fast-growing, light-demanding species of disturbed and secondary forest it is widespread and not of conservation concern, though it is locally significant in agroforestry and as a host for lac and silk insects.

Author: Roxb. · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of British India, Flora of China, Kostermans Sterculiaceae monograph

Acanthaceae

Strobilanthes echinata

by GP Jürgens

Nees

BhutanPG2011 806 01 01
Bhutan Chele-La, 3800m July

Description

Strobilanthes echinata Nees is a shrubby herb of the acanthus family widely distributed through tropical and subtropical Asia, with GBIF documenting 319 occurrences from India (IN), Bhutan (BT), China (CN), Myanmar (MM), Thailand (TH), Vietnam (VN), Indonesia (ID), Malaysia (MY), Laos, Cambodia and Bangladesh. It is a plant of moist forest understorey, shaded slopes, ravines and clearings ranging from the warm lowlands to high temperate elevations. It was photographed in Bhutan on the Chele-La at 3800 m in July, near the upper limit of its range, where it grows in the cool, humid forest belt. The source URL references Strobilanthes wallichii, indicating a synonymous or closely allied treatment.

The plant is a perennial herb or soft shrub with quadrangular, often anisophyllous-leaved stems. The leaves are opposite and decussate, ovate to elliptic, acuminate and toothed, with cystoliths visible as fine streaks, the paired leaves of a node frequently unequal in size as is characteristic of the genus. The flowers are borne in dense, often spiciform or capitate inflorescences subtended by conspicuous, sometimes spiny-tipped or bristly bracts, the epithet echinata alluding to this prickly aspect. The corolla is tubular and curved, five-lobed and blue to violet or pale lilac. The fruit is an elongate, two-valved, explosively dehiscent capsule bearing a few flattened seeds.

Strobilanthes is a large and taxonomically difficult Asian genus famous for its mass-flowering, plietesial life cycle in which whole populations bloom synchronously after several years and then die. Its centre of diversity lies in the Indo-Burmese and Sino-Himalayan region, making it an important element of Asian forest floras. The bird- and insect-pollinated flowers and explosively dispersed seeds aid colonisation of forest gaps. While many species are narrow endemics of conservation concern, S. echinata is comparatively widespread.

Author: Nees · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Strobilanthes monograph (Y. F. Deng & J. R. I. Wood revision)

Acanthaceae

Strobilanthes hamiltoniana

by GP Jürgens

(Steud.) Bosser & Heine

Bhutan2012 992
Bhutan Trithangebe 1100m, October
Bhutan2012 993
Bhutan Trithangebe 1100m, October

Description

Strobilanthes hamiltoniana (Steud.) Bosser & Heine is a shrubby Acanthaceae of the eastern Himalaya and Indo-Burmese region, native to India, Bhutan, Nepal, Myanmar and China, but widely naturalised and cultivated, as reflected in its GBIF total of nearly 779 occurrences spanning many tropical islands and the Americas. In its native range it grows along forest margins, streamsides, ravines and shaded roadbanks in the warm subtropical hill zone, flowering in the late monsoon and autumn. The illustrated plant from Trithangebe in Bhutan at 1100 m in October shows it in its characteristic low-elevation forest-edge habitat at the onset of its flowering season.

The species is an erect, much-branched perennial shrub with four-angled stems and opposite, petiolate, ovate-lanceolate leaves that are acuminate and finely toothed, the pairs typically anisophyllous. The inflorescences are slender, lax, often drooping panicles bearing numerous flowers; each corolla is tubular and gracefully curved, pale violet to mauve-blue with a paler tube, the limb shortly five-lobed, and the androecium of four stamens. The fruit is the typical acanthaceous club-shaped capsule that dehisces explosively to disperse the seeds, which are borne on hooked retinacula.

Strobilanthes is a large and taxonomically difficult Asian genus famed for the gregarious, mast (plietesial) flowering of many species, in which whole populations bloom synchronously after a span of years and then die. S. hamiltoniana is popular in ornamental horticulture for its arching sprays of bloom and consequently appears far beyond its native limits. It is not of conservation concern, being common and readily cultivated.

Author: (Steud.) Bosser & Heine · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Acanthaceae of the Indian Subcontinent, Carine & Scotland revision of Strobilanthes

Styracaceae

Styrax serrulatus

by GP Jürgens

Roxb.

Nepal 97 399 P770
Nepal Arun-Valley 1750m April
Nepal 97 400 P771
Nepal Arun-Valley 1750m April

Description

Styrax serrulatus is a small tree or shrub of the eastern Himalaya and mainland Southeast Asia, distributed from India and Nepal through Bhutan, Bangladesh, Myanmar, Thailand, Laos, Vietnam and southern China to Malaysia and Indonesia, with around 395 GBIF records (the few from Korea and the United States reflecting cultivation). It grows in subtropical to lower-temperate broad-leaved evergreen and mixed forest, forest margins and along streams, generally between about 1,000 and 2,400 m. The plant photographed in the Arun Valley of eastern Nepal at 1,750 m, flowering in April, exemplifies its spring anthesis in the warm, humid mid-elevation forests of the eastern Himalaya.

The plant is a deciduous to semi-evergreen shrub or small tree, the young branchlets, buds and lower leaf surfaces clothed in characteristic stellate hairs. The leaves are alternate, simple, elliptic to ovate-oblong with finely serrulate margins (as the epithet indicates), shortly petiolate and acuminate. The flowers are borne in short axillary or terminal racemes; each is white and fragrant, with a five-lobed campanulate calyx and a five-lobed, deeply divided corolla, the ten stamens united at the base into a short tube. The fruit is a subglobose, dry to leathery drupe-like capsule, often crowned by the persistent calyx, containing one or few seeds.

Styrax is the principal genus of the family Styracaceae, several species of which yield aromatic resins (benzoin). The genus has a notable disjunct distribution between eastern Asia and the Americas, and S. serrulatus belongs to its species-rich Asian assemblage. Widespread and occurring in both primary and secondary forest, it is not considered threatened.

Author: Roxb. · Sources: POWO (Kew), Flora of China Vol. 15, Flora of Bhutan Vol. 2, GBIF, Hwang & Grimes: Styracaceae monographic treatments