N.K.B. Robson (1973) Guttiferae. Flora of West Pakistan 32: 1-12.
Plants much branched shrubs, (0.45)1-2 m tall; stems arching to procumbent or ascending; branches 4-sided initially, soon becoming round in cross-section. Leaves sessile; blades 30-90 mm long, 10-32 mm wide, oblong or ovate-oblong to elliptic, venation more or less densely reticulate, bases cuneate to rounded, tips usually obtuse, rarely acute to apiculate or rounded. Inflorescences of 1-3(-6) flowered cymers. Flowers 3.5-7.5 cm in diameter; sepals 5-8 mm long, ovate to elliptic-oblong, erect in bud, spreading in fruit, margins entire, tips acute to rounded; petals narrowly obovate, 15-30 mm long about a third longer than the stamens; stamens about 30 per bundle; ovary 4-6 mm long; styles about twice as long, free erect or slightly outcurving. Capsules 9-17 mm long, ovoid to ovoid-conic, without oil tubes or vesicles (air-filled cells); seeds about 1 mm long, apiculate, narrowly keeled, seed coats very shallowly linear-foveolate to ribbed scalariform.
Hypericum hookerianum (which used to be known as Hypericumoblongifolium) is common on steep rocks and woodland banks. In Pakistan, it is known from the Salt Range, Hazara, Murree Hills, and Kashmir at 600-2100 m. Its range extends from Kurram in the Western Himalayas to Nepal. It flowers from March to August.
Plants of the World Online (POWO): Hypericum hookerianum. The distribution map shows where the taxon is considered native or introduced but now growing in the wild.
Global Biodiversity Information Facility (GBIF): Hypericum hookerianum. Records may be of cultivated specimens.