Derived from N.K.B. Robson (1980) Hypericaceae. Pp. 363-381
Plants 15-60 cm tall, usually pyramidal in outline; stems 15-55 cm long, erect or decumbent, rarely rooting. Leaves sessile, 2-ranked, amplexicaul, 3-20 mm long, usually triangular-lanceolate, rarely narrowly ovate to linear-oblong, surfaces with few or numerous medium-sized to small translucent dots and an intramarginal rove of black glands, margins undulate. Sepals oblong to ovate-oblong, entire or denticulate, surfaces without black dots, margins without glands, tips rounded or apiculate; anthers with a black glands. Capsules with oil-filled dots or tubes.
Hypericum triquetifolium grows mostly around the Mediterranean and in the Near East, but extends north to Switzerland and Bulgaria. (Based on records in GBIF 2020-08-19)