Tag:

Summer

Hydrangeaceae

Hydrangea stylosa

by G & P Jürgens

Hook. f. & Thomson

Bhutan2012 692
Bhutan Galephu, 850m September
Bh09 216 G363
Bhutan Dochu-La, 3000m June
Bh09 217 P364 2
Bhutan Dochu-La, 3000m June

Description

Hydrangea stylosa Hook.f. & Thomson is a Sino-Himalayan shrub recorded by GBIF from China, Bhutan, India, Vietnam and Japan, with cultivated occurrences from Canada and New Zealand, totalling about 85 records. It occupies a broad altitudinal range in moist broad-leaved and mixed forest, thickets and forest margins, on shaded slopes and along ravines. The Bhutanese material spans this amplitude strikingly, with collections from Galephu at 850 m in September and from the Dochu-La at 3000 m in June, showing occurrence from low submontane forest up into the cool temperate zone.

It is a deciduous shrub with terete branches, the young growth often pubescent and the bark exfoliating on older stems. The leaves are opposite, ovate to oblong-lanceolate, with a serrate margin, an acuminate apex and pinnate venation, pilose along the veins beneath. The inflorescence is a terminal corymbose cyme bearing two kinds of flowers: numerous small fertile flowers with minute petals, and a marginal ring of showy sterile flowers whose enlarged, petaloid white to pinkish sepals attract pollinators. The fertile flowers are notable for their elongate, persistent styles, emphasised by the epithet stylosa; the fruit is a small ribbed capsule opening between the styles.

Within Hydrangea, H. stylosa belongs to the lacecap-type species, in which marginal sterile flowers advertise the fertile centre to insects. Its distribution forms part of the eastern Himalayan to Sino-Japanese floristic continuum, and the species is of horticultural interest, accounting for the cultivated records beyond its native range. As a forest understorey shrub it depends on humid montane woodland.

Author: Hook. f. & Thomson · Sources: POWO (Kew), GBIF, Flora of Bhutan Vol. 1, Flora of China Vol. 8, McClintock monograph of the genus Hydrangea, Flora of Nepal

Apiaceae

Hymenidium benthamii

by GP Jürgens

(Wall. ex DC.) C.B. Clarke

BhutanPG2011 365
Bhutan Jule-Tso 4150m, June
Sikkim2003 159 P212
Sikkim Dzongri 3900m, August
Sikkim2003 160 P213
Sikkim Dzongri 3900m, August

Description

Hymenidium benthamii is a robust alpine umbellifer of the high Himalaya, distributed through Nepal, China, India, Myanmar and Bhutan (gbif_countries: NP, CN, IN, MM, BT), with about 181 GBIF occurrences. It grows in alpine meadows, damp grassy slopes, rocky pastures and streamside flushes above the treeline, where it is a characteristic herb of the moist eastern Himalayan uplands. The illustrated collections span Jule-Tso in Bhutan at about 4150 m, flowering in June, and Dzongri in Sikkim at about 3900 m in August, documenting its occupation of the cool subalpine to alpine zone through the monsoon season.

The plant is a stout perennial arising from a thickened taproot and crown, with erect, ribbed, often hollow stems. The leaves are largely basal, long-petiolate and two- to three-times pinnately divided into toothed or further-dissected segments, the petioles sheathing at the base. The inflorescence is a large, flat-topped compound umbel subtended by a conspicuous involucre of broad, often membranous-margined bracts, a feature recalling the genus name Hymenidium; the small flowers are white to pinkish with five petals. The fruit is a dry schizocarp splitting into two ribbed mericarps, the ridges and oil-canals (vittae) providing key taxonomic characters.

Long known under Pleurospermum benthamii, the species, as the wp_link itself preserves, has been transferred to Hymenidium following revisionary work that dismembered the broadly construed Pleurospermum on molecular grounds. It belongs to the conspicuous-bracted alpine Apiaceae of the Sino-Himalaya, a group much used in regional ethnomedicine. Widespread across its montane range, it is of no conservation concern.

Author: (Wall. ex DC.) C.B. Clarke · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of China, Annotated Checklist of the Flowering Plants of Nepal, Pimenov & Kljuykov revision of Pleurospermum and allied genera

Hypericaceae

Hypericum choisianum

by GP Jürgens

Wall. ex N.Robson

BhutanPG2011 824 01 01
Bhutan Luksor, 2800m July
BhutanPG2011 695 01 01
Bhutan Luksor, 2800m July
Sikkim2003 378 P531
Sikkim Tista valley 3400m August

Description

Hypericum choisianum (correctly H. choisyanum) is a handsome shrubby St John's wort of the Himalaya, distributed from Nepal eastward through India, Sikkim, Bhutan and into southwestern China, with outlying records from Myanmar; cultivated and naturalised material accounts for occurrences in Britain, Ireland and Vietnam, contributing to a GBIF total of over two hundred records. It inhabits open temperate forest, forest margins, scrub, banks and rocky slopes, typically between about 1800 and 3600 m. The plants documented from Luksor in Bhutan at 2800 m in July and from the Tista valley in Sikkim at 3400 m in August reflect both its broad elevational tolerance and its mid-to-late summer flowering, when the large golden blooms are conspicuous along forest edges and clearings throughout the monsoon season.

The plant is an evergreen or semi-evergreen shrub of one to two metres, with arching reddish branches and opposite, ovate to oblong-lanceolate, sessile or clasping leaves that are slightly glaucous beneath and dotted with translucent glands. The flowers are large and showy, solitary or few in terminal cymes, with five broad, bright golden-yellow petals that are often somewhat incurved to give a cupped, almost globose bloom. The numerous stamens are united into five fascicles, and the styles are five, free and spreading. The superior, five-locular ovary develops into a leathery to slightly fleshy capsule that dehisces to release many small seeds; the glandular tissue throughout the plant contains the characteristic hypericin and related compounds.

Hypericum, here placed in the Hypericaceae (sometimes treated within a broadly defined Clusiaceae), reaches notable diversity in the Sino-Himalaya, and H. choisyanum belongs to the large-flowered shrubby section Ascyreia, several members of which are valued as garden ornamentals for their bold yellow flowers and hardiness. Described by N. Robson, who monographed the genus, it is part of a closely allied complex of Himalayan shrubs distinguished by subtle differences in leaf shape, stamen fascicles and capsule form. As a common, ecologically adaptable species spanning a wide range and elevation, it is of no conservation concern, and its frequency along disturbed forest margins reflects considerable tolerance of moderate human modification.

Author: Wall. ex N.Robson · Sources: POWO (Kew), GBIF, Flora of China Vol. 13, Flora of Bhutan Vol. 1 Part 2, Flora of Nepal, Studies in the genus Hypericum (Norman Robson, Bulletin of the British Museum)

Hypericaceae

Hypericum oblongifolium

by G & P Jürgens

Choisy

Garh 07 321JPG ergebnis
India Garhwal Maji 2650, June

Description

Hypericum oblongifolium is a shrubby St John's wort of the family Hypericaceae, native to the western and central Himalaya. GBIF records place it principally in India, Pakistan, Nepal and Afghanistan, with scattered records eastward to Bhutan and occurrences elsewhere representing cultivated plants. It grows on open, rocky hillsides, in scrub, along forest margins and on stream banks in the temperate zone, generally between about 1,500 and 3,000 m. The specimen illustrated from Maji in Garhwal, India, at around 2,650 m in June is typical of this sunny, well-drained mid-montane habitat where the shrub flowers in early summer.

The plant is a much-branched, evergreen to semi-evergreen shrub up to about 1–2 m, with reddish, arching, two-lined younger branches becoming terete with age. The leaves are opposite, sessile to subsessile, oblong to oblong-lanceolate, leathery, with translucent glandular dots, and somewhat glaucous beneath. The flowers are large and showy, golden-yellow, borne singly or in few-flowered terminal cymes; they have five spreading petals, numerous stamens grouped into bundles, and a superior ovary crowned by free styles, conforming to the characteristic Hypericum floral plan. The fruit is a septicidal capsule that splits to release numerous small seeds.

Within the large genus Hypericum the species belongs to the predominantly Asian section of woody, large-flowered shrubs and is closely allied to other Himalayan taxa such as H. hookerianum, from which it is separated by leaf shape, branch character and details of the styles. It is valued horticulturally for its abundant bright flowers and is used locally in folk medicine. Widespread and tolerant of disturbed, open ground, it is not considered threatened, and it readily colonises sunny banks and roadside scrub throughout the western Himalaya.

Author: Choisy · Sources: POWO (Kew), GBIF, Flora of Pakistan, Flora of Nepal, Flora of China Vol. 13, Robson: Studies in the genus Hypericum (Guttiferae)

Acanthaceae

Hypoestes triflora 

by GP Jürgens

(Forssk.) Roem. & Schult.

Nepal 99 997 ergebnis
West-Nepal Juphal 2600m, July

Description

Hypoestes triflora is a broadly distributed paleotropical herb ranging from tropical and southern Africa across the Arabian Peninsula to the Himalaya and southwestern China; its roughly 2040 GBIF records show a strong African centre in South Africa, Ethiopia, Tanzania, Kenya, Cameroon and the Congo basin, with Asian outliers in India, Nepal and China. In the western Himalaya it reaches the mid-montane zone, as in the collection near Juphal in West Nepal at about 2600 m in July, flowering during the monsoon. It grows in shaded, moist situations on forest floors and streambanks, as a soft-stemmed understorey herb of seasonally wet temperate and subtropical woodland.

The plant is an erect to straggling herb with four-angled, swollen-noded stems rooting at the lower joints. The opposite leaves are ovate to lanceolate, thin-textured and acuminate, with entire to obscurely toothed margins. The flowers are grouped in small axillary clusters, each subtended by bracts and typically containing three flowers, as the epithet records. The bilabiate corolla is pale pink to lilac or purplish, with a slender tube and deeply two-lipped limb. The fruit is an explosively dehiscent club-shaped capsule that ejects its seeds from retinacula-bearing placentae.

Within Acanthaceae, Hypoestes is allied to Justicia and recognised by its bracteate flower clusters and two-locular capsules; H. triflora is among the most wide-ranging species, its disjunct African-Asian distribution reflecting historical connections across the paleotropics. As a common woodland herb spanning many countries, it is of no particular conservation concern.

Author: (Forssk.) Roem. & Schult. · Sources: POWO (Kew), GBIF, Flora of China Vol. 19, Flora of Bhutan Vol. 2, Flora of Nepal, Flora of Tropical East Africa (Acanthaceae)

Hypoxidaceae

Hypoxis aurea

by GP Jürgens

Lour.

Nepal 97 491 P962
Nepal Num 1650m May
Nepal 99 198 ergebnis
West-Nepal Lara-Lake 2900m, June

Description

Hypoxis aurea Lour. is a small cormous geophyte of the Hypoxidaceae with a wide Asian and Pacific distribution, recorded from India, Nepal, Bhutan, Sri Lanka and China through Taiwan, Japan and Korea, across Southeast Asia (Myanmar, Thailand, Vietnam, Laos, Cambodia, Indonesia, the Philippines) to New Guinea, with around 1,240 georeferenced occurrences. It grows in open, well-lit grassy habitats: hill grassland, open pine and oak woodland, pasture, terrace banks and disturbed slopes, often in seasonally moist soils. The photographed plants from Num at about 1,650 m and from the Lara-Lake area of West Nepal at about 2,900 m, flowering in May and June, show its broad altitudinal span from subtropical foothills to the lower-temperate zone in the Himalaya.

It is a perennial herb arising from a small ovoid to tuberous corm. The leaves are all basal, several, narrowly linear and grass-like, often keeled and clothed (especially toward the base) in long soft hairs. The flowers are borne singly or few together on slender scapes shorter than or about equalling the leaves; each has six spreading yellow tepals, golden within and frequently greenish and hairy on the outer surface, with six stamens and an inferior, hairy ovary. The fruit is a small capsule opening to release numerous tiny black, often muricate seeds.

Hypoxis is a chiefly tropical and warm-temperate genus of grassland geophytes, and its members are well adapted to fire and seasonal drought through the perennating corm, which resprouts after burning or dry-season dormancy. The yellow, pollen-rich, nectarless flowers attract pollen-gathering insects. Widely distributed and frequently associated with grazed and disturbed grassland, H. aurea is common across its range and not considered threatened.

Author: Lour. · Sources: POWO (Kew), Flora of China Vol. 24, Flora of Bhutan Vol. 3, GBIF, Nordal: Hypoxidaceae (in Kubitzki, 1998)

Brassicaceae

Ianhedgea minutiflora

by G & P Jürgens

(Hook.f. & Thomson) Al-Shehbaz & O’Kane

Nepal 99 819 ergebnis
West-Nepal Baga-La-Phedi 4300m, July

Description

Ianhedgea minutiflora is a diminutive, high-alpine crucifer with a broadly Irano-Turanian to western Himalayan distribution, recorded from Afghanistan, Pakistan, northern India, Tajikistan and Iran, and extending eastward into western Nepal. It is a plant of open, stony and gravelly ground, scree slopes, glacial moraines and dry alpine meadows at high elevations, typically between about 3,500 and 4,800 m. The collection from Baga-La-Phedi in West Nepal at 4,300 m in July reflects its occurrence in the cold, well-drained, sparsely vegetated terrain of the upper alpine zone, where the short summer growing season governs its rapid flowering.

The plant is a small annual or short-lived herb with slender, simple to branched stems arising from a thin taproot. The leaves are entire to slightly toothed, oblanceolate to spathulate and mostly basal. The inflorescence is a lax, ebracteate raceme bearing minute, inconspicuous flowers with four whitish petals scarcely exceeding the sepals, giving the species its epithet. The fruit is a small, linear, terete to slightly compressed silique that is sessile or shortly stipitate, dehiscing to release tiny seeds arranged in a single row per locule.

The genus Ianhedgea was segregated by Al-Shehbaz and O'Kane and named in honour of the cruciferologist Ian Charleson Hedge; the species was formerly placed in Sisymbrium and related genera, its basionym attributed to Hooker f. and Thomson. The transfer reflects molecular and morphological reassessment of the tribe Sisymbrieae. As an inconspicuous, widespread high-mountain annual, it faces no recognised conservation threat but is poorly documented owing to its small size and remote habitat.

Author: (Hook.f. & Thomson) Al-Shehbaz & O'Kane · Sources: POWO (Kew), Flora of Pakistan, Annotated Checklist of the Flowering Plants of Nepal, GBIF, Al-Shehbaz: Cruciferae systematics

Balsaminaceae

Impatiens discolor

by GP Jürgens

DC.

Bh09 286 P469
Bhutan Tongtsa 2100m, June

Description

Impatiens discolor is an annual herb of the eastern Himalaya and adjoining ranges, documented by GBIF from Nepal, India, Bhutan, China, Thailand and Papua New Guinea across roughly 78 occurrences, several records being indeterminate as to country. It favours shaded, humid montane forest, growing along stream banks, in moist gullies and on seepage-fed roadside banks within evergreen and mixed broad-leaved woodland, typically at middle elevations. The photographed plant from Tongsa (Trongsa) in central Bhutan at about 2100 m, flowering in June with the onset of the monsoon, is typical of the warm, wet conditions that the genus exploits during the rainy season.

The plant has a succulent, translucent, often reddish stem that is erect or ascending and watery in texture, with swollen nodes. The leaves are alternate, ovate to elliptic, with a serrate or crenate-serrate margin and an acuminate apex, frequently glaucous or paler beneath, giving the discolorous appearance referenced by the epithet. The zygomorphic flowers are borne singly or in few-flowered axillary clusters; the lower sepal forms a saccate spur, and the showy yellow corolla (sometimes spotted) is built from a standard and two lateral united petals. The fruit is a fleshy, club-shaped capsule that dehisces explosively, the valves coiling abruptly to fling the seeds well away from the parent.

Balsaminaceae are notoriously taxonomically difficult, with Impatiens hyper-diverse and richly speciose in the Sino-Himalaya, where rapid radiation has produced many narrowly distributed, ecologically specialised taxa. Explosive seed dispersal and dependence on insect pollinators, together with a strictly annual life cycle, tie the species closely to seasonal monsoon moisture. While not formally assessed as threatened, the group's fine-scale habitat specificity makes individual populations sensitive to forest disturbance and altered rainfall regimes.

Author: DC. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Grey-Wilson "Impatiens of Africa" and Sino-Himalayan Impatiens monographic studies

Balsaminaceae

Impatiens falcifer 

by G & P Jürgens

Hook.f.

Sikkim2003 66 P89
Sikkim Choka 2900m, August

Description

Impatiens falcifer is an eastern Himalayan balsam with a restricted distribution spanning Nepal, Sikkim, Bhutan, and adjacent parts of southern China (Xizang). GBIF records list 67 occurrences, indicating a comparatively uncommon species. It is found in moist, sheltered habitats within temperate and subalpine forests, including shaded stream banks, mossy rock faces, and forest margins, at elevations of 2,200–3,500 m. The species frequently grows among ferns and other shade-tolerant herbaceous perennials in areas of high humidity.
Impatiens falcifer is an erect, succulent annual herb, 30–60 cm tall, with glabrous, translucent stems that are often reddish-tinged at the nodes. Leaves are alternate, elliptic to ovate-lanceolate, 5–12 cm long, with serrate margins bearing small glandular teeth; the petioles are slender, 1–3 cm long. Flowers are borne in few-flowered axillary racemes. The flowers are yellow, often with reddish spots in the throat, 2–3 cm long, with a deeply saccate lower sepal that narrows into a conspicuously curved or falcate spur — the defining character from which the epithet derives. The lateral united petals are bilobed, the upper lobe ovate, the lower lobe distinctly falcate. The fruit is a fusiform capsule that dehisces explosively when ripe, a characteristic of the genus.
Described by Joseph Dalton Hooker from Sikkim collections, Impatiens falcifer belongs to the large and taxonomically challenging eastern Himalayan radiation of the genus. The photographed specimen from Choka in Sikkim at 2,900 m represents a typical mid-elevation occurrence in cloud-forest habitat. The species can be distinguished from superficially similar yellow-flowered congeners such as I. urticifolia by the strongly curved spur and falcate petal lobes. Its narrow geographical range and dependence on intact moist forest habitats suggest potential vulnerability to deforestation and land-use change.

Author: Hook.f. · Sources: POWO (Kew), GBIF, Flora of British India Vol. 1 (Hooker 1875), Grey-Wilson: Impatiens of Africa (1980), Akiyama et al. (1993)

Balsaminaceae

Impatiens spirifer

by G & P Jürgens

Hook.f. et Thomson

Bhutan2015 60
Bhutan Wangdi Phodrang 2000m, October
Bhutan2015 59
Bhutan Wangdi Phodrang 2000m, October
BhutanPG2011 37
Bhutan Pele-La, 2800m June
Bhutan2012 1338
Bhutan Pemagatse, 2000m October

Description

Impatiens spirifer is an annual balsam of the eastern Himalaya, recorded by GBIF in some 52 occurrences from India, China, Bhutan and Nepal. It favours cool, shaded and humid situations such as forest margins, ravine banks, seepage slopes and roadside ditches in the temperate and upper-subtropical belt, broadly between 1800 and 3000 m. The accompanying images were taken in Bhutan at Wangdi Phodrang and Pemagatse (2000 m, October) and the Pele-La (2800 m, June), documenting a long flowering season that extends through the monsoon into autumn on moist, organic-rich soils where balsams thrive.

The plant is a succulent, glabrous herb with translucent, often reddish-tinged stems that are erect to ascending and somewhat swollen at the nodes. The leaves are alternate, ovate to elliptic, crenate-serrate with the lowermost teeth sometimes gland-tipped, narrowing to a petiole. The flowers are zygomorphic and resupinate, borne singly or in few-flowered axillary clusters; the lower sepal forms a navicular spur that is slender and incurved, while the lateral united petals are deeply two-lobed. The fruit is a fleshy, fusiform capsule that dehisces explosively, the valves coiling to fling out the small seeds.

Impatiens (Balsaminaceae) is among the largest angiosperm genera, exceptionally species-rich and rapidly radiating in the Sino-Himalayan region, where narrow endemism and floral micromorphology drive species delimitation. GBIF treats I. spirifer as accepted. Like many montane balsams it is closely tied to perennially moist microhabitats and is thus vulnerable to drainage, disturbance and shifts in monsoon reliability, although it remains locally frequent within suitable forest.

Author: Hook.f. et Thomson · Sources: POWO (Kew), GBIF, Flora of Bhutan, Flora of China, Grey-Wilson monograph of Impatiens (Balsaminaceae)