HELIOTROPIUM

Heliotropium Tourn. ex L., Sp. Pl. 130. 1753; Gen. Pl., ed. 5. 63. 1754; Clarke in Hook. f., Fl. Brit. Ind. 4: 148. 1885; Fl. China @ eFloras.org 16: 338; Nasir, Fl. Pak. @ eFloras org. p.18.

Annual or perennial, prostrate to erect herbs or undershrubs, pubescent to strigose, rarely scabrous or glabrous. Leaves alternate, simple, entire. Inflorescence usually of terminal or axillary scorpoid cyme. Flowers bisexual, actinomorphic, 5-merous, hypogynous, small, white, bracteate or not. Calyx usually 5-partite, lobes linear or lanceolate, persistent. Corolla white or light bluish-purple, less often yellow, 5-lobed, tubular to funnelform, hairy on outside, sometimes also within, lobes +/- erect or inflexed, obtuse to linear, with dentations or lobed between them or not. Stamens 5, free, included, inserted in corolla tube; anthers elongated, subsessile, sometimes apiculate. Ovary 4-lobed, 4-locular or incompletely 2-locular, ovules 4; style erect; stigma +/- conical or elongated; stigmatic disc usually present. Fruit nutlet like dry drupes (without evident mesocarp at maturity), endocarp bony, dividing into four 1-seeded or two 2-seeded mericarps. Seeds straight or curved.

250 species

Heliotropium europaeum

Heliotropium europaeum L., Sp. Pl. 1: 130. 1753; Fl. China @ eFloras.org; H. majus Garsault, Fig. Pl. Med. t. 299. 1764.

Herbs, annual, 20-65 cm tall. Stems erect, spreading or ascending, branched from base, branches green or greyish-green, dense white hairs from bulbous base, strigose or hirtellous. Leaves alternate, simple; petiole 1.5-3.5 cm long, hirtellous; leaf blade 3-5.5 cm x 2.5-4.0 cm, elliptic, ovate, elliptic-ovate, abaxially grey-green and densely hirtellous, adaxially green and sparsely hirtellous, base widely cuneate to rounded, apex obtuse to acute. Inflorescence terminal or axillary scorpoid cyme, 3.5-6.2 cm long, simple or dichotomously branched, with closely set biseriate flowers. Flowers sessile, bisexual, actinomorphic, 5-merous, hypogynous, ebracteate. Calyx 5-partite, lobes ovate-lanceolate, 1.5-2.5 mm x 1-1.5 mm, not enlarged in fruits, hirtellous outside, glabrous inside, persistent. Corolla white with yellow throat, 3.5-4.0 mm long, tubular with spreading limbs, base 1.5-2 mm wide, throat slightly constricted; limb 3-4 mm wide, lobes +/- orbicular, 1.2-1.5 mm x 1.2-1.5 mm, sinuses often with appends, short strigose outside and glabrous inside. Stamens 5, free, included, attached ca. 1 mm above base of corolla tube; anthers ovate-oblong, ca. 1 mm long; filaments none. Carpels 2, syncarpous; ovary globose, shortly strigillose, 4-lobed, 0.5-0.7 mm in diameter and 4- locular, each loculus with one ovule; style erect and short, ca. 0.5 mm; stigma long, conical, 1.2-1.5 mm long, simple, occasionally 2-cleft, ring-like portion above style glabrous, strigose above. Fruit 2.5-3 mm in diameter, nutlet like dry drupes, endocarp bony, dividing into 4 one-seeded mericarps; mericarps ovate, ca. 2 mm, +/- distinctly tuberculate, glabrous, brown.

Flowering and Fruiting: April to July
Common Names: : Common Heliotrope, Potato Weed, European Heliotrope, European Turn- sole; Caterpillar Weed