Tag:

Spring

Saxifragaceae

Saxifraga vacillans

by G & P Jürgens

Harry Sm.

Bhutan2014 929
Bhutan Chele-La 4100m, May
Bhutan2014 928
Bhutan Chele-La 4100m, May

Description

Saxifraga vacillans Harry Sm. is a high-alpine cushion- to mat-forming saxifrage of the eastern Himalaya, known from only a handful of georeferenced collections, all from Bhutan. It is a plant of the upper alpine zone, growing among rocks, on stabilised scree, in moist turf and in the crevices of cliffs and moraines well above the treeline. The single documented locality at Chele-La, photographed at 4,100 m in May, is characteristic of its narrow elevational preference for sites between about 3,800 and 4,500 m, where it endures intense insolation, freeze-thaw cycles and a short snow-free growing season.

The species forms low, compact tufts or loose cushions from a branched, somewhat woody caudex. The leaves are small, crowded into basal rosettes, narrowly spathulate to oblong and entire or obscurely toothed, often slightly fleshy and ciliate at the margins, adaptations reducing water loss in the desiccating alpine environment. Flowering stems are short and few-flowered, bearing solitary or few yellow flowers; each flower has five spreading petals, often dotted with orange near the base, ten stamens, and a bicarpellate, partly inferior ovary maturing into a capsule that releases numerous minute seeds.

Saxifraga vacillans belongs to the large and taxonomically complex genus Saxifraga, the yellow-flowered Himalayan members of which (section Ciliatae and allies) form a notoriously difficult species complex. Its apparent rarity and restriction to Bhutan may partly reflect under-collection in remote alpine terrain rather than genuine narrow endemism. Nonetheless, as a specialised high-elevation taxon it is potentially vulnerable to upslope habitat compression driven by climate warming, underscoring the value of continued botanical survey in the Bhutanese high passes.

Author: Harry Sm. · Sources: POWO (Kew), GBIF, Flora of Bhutan Vol. 1, Flora of China Vol. 8, Pan et al.: Monograph of Saxifraga (Saxifragaceae)

Theaceae

Schima wallichii

by GP Jürgens

()DC.) Choisy

Bhutan2014 769
Bhutan Wangdi Punaka 1400m, May
Bhutan2014 769
Bhutan Wangdi Punaka 1400m, May
Nepal 1994 322 ergebnis
Ost-Nepal Chainpur 1300m May 

Description

Schima wallichii is a large evergreen tree distributed across the eastern Himalaya and Southeast Asia, with GBIF records from China, Indonesia, Malaysia, Thailand, India, Nepal, Myanmar, Vietnam, Laos, Bhutan, the Philippines, Cambodia and Bangladesh among others, totalling around 3706 occurrences. It is a dominant or co-dominant canopy element of subtropical and lower montane broadleaved forest, frequently a pioneer that colonises forest gaps, secondary woodland and abandoned cultivation on humid hill slopes. The trees photographed at Wangdi-Punakha in Bhutan at about 1400 m and at Chainpur in eastern Nepal at about 1300 m, both in May, illustrate its prevalence in the warm subtropical mid-hill forests of the southern Himalayan front, where it often forms extensive stands with oaks and laurels.

It is an evergreen tree with grey, longitudinally fissured bark and reddish young shoots. The leaves are alternate, coriaceous, elliptic to oblong-lanceolate, entire or obscurely serrate, glabrous and glossy above and somewhat paler beneath. The flowers are solitary or few in the upper leaf axils, large and showy, with five white petals surrounding a dense central mass of numerous yellow stamens, the whole subtended by silky sepals and bracteoles and emitting a sweet fragrance. The fruit is a woody, globose, loculicidal capsule that splits into valves to release flattened, broadly winged seeds adapted to wind dispersal.

A member of the tea family (Theaceae), Schima wallichii is an ecologically important successional and timber species, its hard wood widely used in construction, while the bark and other tissues contain irritant saponins. Its winged seeds and gap-colonising habit make it an effective coloniser of disturbed montane forest, contributing to forest regeneration and watershed protection. Broadly distributed and often abundant, the species is not of conservation concern; rather it is silviculturally valued and frequently retained or planted in mixed broadleaved forestry across its range.

Author: ()DC.) Choisy · Sources: POWO (Kew), GBIF, Flora of China Vol. 12, Flora of Bhutan Vol. 1, Flora of Nepal, Bloembergen A Critical Study in the Complex-Polymorphous Genus Schima (Theaceae)

Schisandraceae

Schisandra grandiflora

by GP Jürgens

(Wall.) Hook.f. & Thomson

Sikkim2011 189
Sikkim Lachung 2800m, June
Bh09 249 G417
Bhutan Pele-La, 3100m June
Sikkim 2006 7 ergebnis
India West-Bengal Maneybhajang 2000m, May

Description

Schisandra grandiflora (Wall.) Hook.f. & Thomson is a deciduous, woody climber of the eastern Himalaya, recorded by GBIF from China, India, Nepal, Bhutan and Myanmar. It is a plant of cool, humid temperate forest, growing in mixed broad-leaved and conifer woodland, along forest margins and ravines, where it scrambles over shrubs and into the canopy, generally between about 2,000 and 3,500 m. The cited collections span Lachung in Sikkim at 2,800 m and Pele-La in Bhutan at 3,100 m in June, and Maneybhajang in West Bengal at 2,000 m in May, illustrating its broad occurrence across the moist temperate forest belt of the eastern Himalayan arc.

The plant is a glabrous, twining liana with slender woody stems and alternate, simple leaves that are elliptic to obovate, with serrulate margins and an acuminate apex, borne on reddish petioles. As in all Schisandraceae the flowers are unisexual, the species being dioecious or monoecious; they are solitary and pendulous on slender pedicels, comparatively large for the genus (hence grandiflora), with several white to creamy or pink-tinged perianth segments not differentiated into sepals and petals. The numerous free carpels of the female flower, borne on an elongating receptacle, ripen into a pendent, spike-like aggregate of red, fleshy berries.

Schisandraceae, together with the related Illiciaceae, occupy a basal position among the angiosperms in the order Austrobaileyales, making the family of major significance in studies of early flowering-plant evolution. Several Schisandra species, notably S. chinensis, are renowned medicinal plants, and the aromatic fruits of S. grandiflora are likewise used locally. Its disjunct Sino-Himalayan distribution reflects the ancient, relictual biogeography characteristic of this lineage.

Author: (Wall.) Hook.f. & Thomson · Sources: POWO (Kew), GBIF, Flora of China Vol. 7, Flora of Bhutan Vol. 1, Saunders: Monograph of Schisandra (Systematic Botany Monographs)

Schoepfiaceae

Schoepfia griffithii

by GP Jürgens

Tiegh. ex Steenis

Bh2008 527 P803
Bhutan Limbukha 1400m, May
Bh2008 528 P804
Bhutan Limbukha 1400m, May

Description

Schoepfia griffithii is a small tree or shrub of the family Schoepfiaceae, a hemiparasitic member of the sandalwood order Santalales. Its GBIF records are confined to Bhutan, India, China and Myanmar, indicating a restricted eastern Himalayan to northern Indochinese distribution. It occurs in subtropical and warm-temperate broad-leaved forest, on hill slopes, ridges and forest margins, typically between about 1,000 and 1,800 m. The collection illustrated from Limbukha in western Bhutan at around 1,400 m in May is representative of this mid-elevation evergreen forest, where the plant flowers in spring.

The species is a slender, much-branched shrub or small tree with smooth bark and glabrous twigs. The leaves are alternate, simple and entire, ovate to elliptic, leathery and shortly petiolate, with a somewhat acuminate apex. The flowers are small and borne in short axillary racemes or fascicles; the corolla is tubular to campanulate, usually creamy to greenish-yellow, with a small number of lobes and stamens inserted opposite the lobes, set on a partly inferior ovary surrounded by a small disk. The fruit is a small ovoid drupe-like structure enclosed by the persistent, accrescent perianth and receptacle, ripening to a coloured fleshy body attractive to birds.

As a root hemiparasite Schoepfia attaches to the roots of neighbouring trees through haustoria while remaining photosynthetic, a habit shared across the Santalales. The segregation of Schoepfiaceae from the older broadly circumscribed Olacaceae follows molecular phylogenetic studies that resolved the order into more natural families. With a narrow range and a habitat under pressure from forest clearance, S. griffithii is of biogeographic interest as a relatively poorly known component of the eastern Himalayan parasitic flora.

Author: Tiegh. ex Steenis · Sources: POWO (Kew), GBIF, Flora of China Vol. 5, Flora of Bhutan Vol. 1, Nickrent: Phylogeny of Santalales, Flora of Bhutan supplementary checklist

Rubiaceae

Scleromitrion verticillatum

by G & P Jürgens

(L.) R.J.Wang

Sikkim 2006 280 ergebnis
India West-Bengal, Chaana 1650m, May

Description

Scleromitrion verticillatum is a widespread herb of tropical and subtropical Asia, with 629 GBIF occurrences spanning India, Nepal, China, Taiwan, Japan and a broad swathe of Southeast Asia from Myanmar and Vietnam through Malaysia, Indonesia and the Philippines. It grows as a weedy annual or short-lived perennial of open, disturbed and seasonally moist ground, including roadsides, grassy banks and waste places from the lowlands into the lower hills. The plant recorded at Chaana in West Bengal at 1650 m in May reflects its presence in the eastern Himalayan foothills, where it flowers with the onset of the warm, pre-monsoon season.

The species is an erect to ascending herb with quadrangular, often scabrid stems that may be roughened on the angles. The leaves are opposite, sessile or nearly so, linear-lanceolate to lanceolate, with entire, frequently scabrid margins and interpetiolar stipules bearing setae characteristic of the tribe Spermacoceae. The small white flowers are borne in dense axillary clusters or verticillate glomerules, each with a four-lobed calyx, a tubular four-lobed corolla, four epipetalous stamens and a bifid style. The fruit is a small, subglobose to ellipsoid capsule that dehidces septicidally to release numerous minute, angular seeds.

Scleromitrion was segregated from the broadly circumscribed Hedyotis-Oldenlandia complex on the basis of molecular and capsular characters, and S. verticillatum was formerly placed in Hedyotis and Oldenlandia. The genus belongs to the tribe Spermacoceae within Rubioideae. As a ruderal coloniser of open habitats, the species is ecologically successful and locally common, posing no conservation concern across its extensive range.

Author: (L.) R.J.Wang · Sources: POWO (Kew), GBIF, Flora of China Vol. 19, Flora of Bhutan Vol. 2, Flora of Nepal, Flora of Pakistan, Wang's revision of Scleromitrion and Spermacoceae

Loranthaceae

Scurrula elata

by GP Jürgens

Danser

Bhutan2012 994
Bhutan Trithangebe 1000m, October
Bhutan2012 995
Bhutan Trithangebe 1000m, October
Nepal 97 307 P610
Nepal Honggaon 2360m May
Nepal 97 308 P611
Nepal Honggaon 2360m May

Description

Scurrula elata is a hemiparasitic mistletoe of the eastern and central Himalaya, recorded from Nepal, China, Bhutan and India, with around 200 occurrences in GBIF. As an obligate stem parasite it occurs wherever suitable woody host trees grow in subtropical to warm temperate broad-leaved forest, hill forest and forest edges, drawing water and minerals from its host through a haustorial connection while photosynthesising in its own leaves. Its altitudinal spread is shown by the cited material from Trithangebe in Bhutan at 1000 m, in flower in October, and from Honggaon in Nepal at 2360 m in May, indicating a range across the lower and mid montane forest belt where host diversity is high.

The plant forms a pendent to spreading parasitic shrublet attached to host branches by a swollen haustorial union. The young stems and foliage are clothed in a brownish to rusty stellate or dendritic tomentum. The leaves are opposite or subopposite, ovate to elliptic, entire and shortly petiolate. The flowers are arranged in short axillary racemes and are characteristically zygomorphic, with a slender, curved, tubular corolla that splits along one side as it opens, ranging from greenish to reddish in colour; the calyx is borne on an elongate, club-shaped receptacle. The fruit is a small, club-shaped (turbinate) berry, narrowed below, containing a single viscin-coated seed adapted for bird dispersal and adhesion to new host branches.

Scurrula is a genus of the showy mistletoe family Loranthaceae, distinguished within the family by its pear- or club-shaped fruit and curved, one-sided corolla, and centred on tropical and subtropical Asia. As with other loranths, its flowers are typically pollinated by birds, and its seeds are spread by frugivorous birds such as flowerpeckers that wipe the sticky seeds onto branches. Heavy infestation can damage host trees, but the species is a natural component of Himalayan forest canopies, is widespread within its range and is not considered threatened.

Author: Danser · Sources: POWO (Kew), GBIF, Flora of China Vol. 5, Flora of Bhutan Vol. 1, Flora of Nepal, The Loranthaceae of the Indomalayan Region (Danser)

Crassulaceae

Sedum triactina

by GP Jürgens

A. Berger

Bhutan2012 328
Bhutan Dochu-La 3200m, September
Bhutan2014 35
Bhutan Trashigang 1570m, May

Description

Sedum triactina is a succulent herb of the eastern Himalaya and Sino-Himalayan region, recorded from China, Nepal, India and Bhutan; its c. 329 georeferenced records span a wide temperate to subalpine altitudinal range. It grows on damp rocks, mossy banks, cliff ledges, stream margins and forest floor, generally between 1500 and 3500 m. The two Bhutanese localities documented in the image, Dochu-La at 3200 m in September and Trashigang at 1570 m in May, illustrate the species' broad ecological tolerance, occurring both in cool subalpine forest passes and warmer mid-elevation valleys.

It is a small, fleshy perennial herb with slender, often decumbent to ascending stems rising from a delicate creeping base, sometimes rooting at the nodes. The leaves are succulent, alternate, oblong to spathulate, entire and rather flat, glabrous and somewhat glaucous. The inflorescence is a lax, few-flowered terminal cyme. The flowers are typically pentamerous (the epithet "triactina" alluding to a three-rayed or three-parted character in some flowers), with narrow, spreading, pale yellow to greenish-yellow or whitish petals, ten stamens, and free or basally connate carpels. The fruit comprises several spreading, many-seeded follicles releasing minute seeds.

Described by A. Berger, S. triactina belongs to the large genus Sedum of the stonecrop family Crassulaceae, a group employing CAM photosynthesis as an adaptation to the desiccating conditions of rock and cliff microhabitats. Its small flowers are visited by generalist insects, and vegetative fragmentation supplements seed reproduction. The species is widespread and locally common across its montane range, with no recognised conservation concern, persisting readily on disturbed rocky and roadside substrates.

Author: A. Berger · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Flora of Nepal, 't Hart & Bleij's account of Sedum (Crassulaceae)

Dipterocarpaceae

Shorea robusta

by GP Jürgens

C.F.Gaertn.

Nepal 97 35 P54
Nepal Dhoban 800m April
Nepal 97 37 P56
Nepal Dhoban 800m April
Nepal 1994 33 ergebnis
Ost-Nepal Simbhuwa Kola 
1000m April

Description

Shorea robusta, the sal tree, is a large, often gregarious dipterocarp dominating extensive lowland and submontane forests of the Indian subcontinent, documented by GBIF (596 occurrences) from India, Nepal, Bangladesh, Bhutan and adjacent regions. It forms the characteristic sal forest of the outer Himalayan foothills, terai and plains, on deep, well-drained alluvial and lateritic soils, typically below about 1200 m. The gatherings from Dhoban at 800 m and the Simbhuwa Kola in East Nepal at 1000 m, both in April, capture its phenology in the foothill belt, where it flushes new leaves and flowers in the hot pre-monsoon season.

The tree is large and may exceed 30 m, with a straight bole, thick longitudinally fissured bark and a dense, spreading crown; in moist sites it is nearly evergreen, briefly leaf-exchanging in the dry season. The leaves are simple, alternate, ovate-oblong, glabrous, shining and acuminate. The fragrant, pale yellow flowers are borne in axillary and terminal panicles, each with five sepals, five petals and numerous stamens. The fruit is a single-seeded nut crowned by the persistent, accrescent calyx, three lobes of which enlarge into elongate, wing-like sepals that aid wind dispersal.

A keystone of the Dipterocarpaceae in South Asia, sal is renowned for its durable timber, its dammar resin and its periodic mast-flowering, in which whole stands fruit synchronously. Ecologically it is a strong dominant forming nearly monospecific canopies and supporting a distinctive forest fauna and flora. Although heavily exploited and locally reduced by clearance, the species remains widespread and is not globally threatened, while being central to forestry and conservation in the region.

Author: C.F.Gaertn. · Sources: POWO (Kew), GBIF, Flora of Bhutan Vol. 1, Flora of Nepal, Flora of Pakistan, Ashton Dipterocarpaceae monograph (Flora Malesiana)

Iridaceae

Sisyrinchium angustifolium

by GP Jürgens

Mill.

Bhutan2014 108
Bhutan Trashigang 1550m, May

Description

Sisyrinchium angustifolium, the narrow-leaved blue-eyed grass, is native to eastern North America (US, CA) but is widely naturalised, with more than 15,000 GBIF occurrences extending across western Europe (FR, ES, IE, GB, DE, BE), eastern Asia (KR, JP) and elsewhere. In the Himalaya it occurs as an introduced and locally established plant of damp meadows, lawns, ditches and grassy roadsides. The individual recorded at Trashigang in eastern Bhutan at 1550 m in May reflects its naturalisation in moist, open, subtropical to warm-temperate grassland, where it flowers in spring on seasonally moist ground.

Despite the common name it is no grass but a tufted perennial of the Iridaceae, forming clumps of narrow, linear, equitant leaves arising in two ranks from a short rhizome. The flowering stems are markedly flattened and conspicuously winged, often branched, and bear terminal clusters of flowers subtended by paired green spathes. Each ephemeral flower has six spreading blue to violet tepals abruptly apiculate with a small terminal mucro, contrasting with a yellow centre; the three stamens have filaments united into a tube around the style. The fruit is a small globose to obovoid loculicidal capsule containing numerous black, rounded seeds.

The species belongs to the large American genus Sisyrinchium and is taxonomically complex, with several allied microspecies and frequent confusion with S. montanum and S. bermudiana. Its flowers open only in sunshine and are bee-pollinated, while prolific seed favours self-establishment in mown swards. Outside its native range it behaves as a benign garden escape.

Author: Mill. · Sources: POWO (Kew), GBIF, Flora of Bhutan Vol. 3, Flora of Nepal, Flora of China Vol. 24, The Genus Sisyrinchium (Iridaceae) Monograph

Rutaceae

Skimmia multinervia

by GP Jürgens

C.C. Huang

Bhutan2014 596
Bhutan Phobjika 2400m, May
Nepal 1994 84 ergebnis
Ost-Nepal Jaljale Himal
3000m April

Description

Skimmia multinervia is an evergreen shrub of the eastern Himalaya and adjacent China, with GBIF records (about 294) confined to China and Bhutan but its wider native range extending along the Himalaya into Nepal and northeastern India. It occupies the cool, humid montane and subalpine forest zone, as shown by collections at Phobjika in Bhutan around 2400 m in May and on the Jaljale Himal in eastern Nepal near 3000 m in April. There it grows in the shaded understorey of broad-leaved and conifer forest, among rhododendrons and on mossy slopes, favouring moist, organic-rich, well-drained soils.

The plant is a compact, much-branched aromatic shrub whose foliage releases a pungent citrus scent when crushed, owing to the translucent oil glands typical of Rutaceae. The leaves are alternate, often crowded toward the branch tips, elliptic to oblanceolate, leathery and entire, with the numerous lateral veins to which the epithet refers. The species is functionally dioecious, bearing small whitish to cream flowers in terminal panicles with four to five petals; male and female plants must grow together for fruit to set. The fruit is a fleshy, bright red drupe persisting through the colder months and dispersed by birds.

Skimmia is a small Asian genus within the citrus family, distinguished by its evergreen aromatic habit, dioecy and red drupaceous fruits; its species, including S. multinervia, are valued in temperate horticulture for winter colour. As a forest-understorey shrub dependent on intact, moist montane woodland, it is sensitive to forest clearance and grazing, though across its range it remains locally frequent and is not regarded as globally threatened.

Author: C.C. Huang · Sources: POWO (Kew), GBIF, Flora of China Vol. 11, Flora of Bhutan Vol. 1, Flora of Nepal, A Monograph of the Genus Skimmia (Rutaceae)