TRIBULUS

Tribulus L., Sp. Pl. 386. 1753; Gen. Pl. 5: 183. 1754; DC., Prodr. 1: 703. 1824; Benth. & Hook. f., Gen. Pl. 1: 264. 1862; Edgeworth & Hook. f. in Hook. f., Fl. Brit. India 1: 423. 1875; Engler in Engler & Prantl., Natur. Pflanzenfam. ed. 2, 19 a: 176. 1931; Hutch., Gen. Fl. Pl. 2: 618. 1968; Fl. China @ eFloras.org 11: 49; Fl. Pak. @ eFloras.org p. 21.

Annual to perennial, prostrate to decumbent, pubescent to glabrescent herbs. Leaves opposite, one of each alternating smaller, sometimes abortive, paripinnate; stipules lanceolate to subulate; leaflets 3-10 pairs, opposite, shortly petiolulate to sessile, oblique, oblong to ovate or elliptical. Flowers solitary axillary, pedicellate, actinomorphic, bisexual, 5-merous, hypogynous, yellow, rarely white. Sepals 5, free, imbricate, pubescent, caducous or persistent. Petals 5, free, spreading, obovate to oblong-obovate, fugacious. Stamens 10, in 2 whorls of 5 each; stamens of outer whorl slightly longer and are opposite the petals while stamens of inner whorl shorter and alternate with petals; rarely stamens 5; each of the inner whorl of 5 stamens subtended adaxially by intrastaminal gland and abaxially by extrastaminal gland; filaments unappendaged; anthers oblong. Disc annular, fleshy, 10-lobed. Carpels 5, syncarpous; ovary superior, sessile, ovoid or globose, beset with long silky hairs, 5-locular, each loculus with 2-5(-10) obliquely pendulous superposed ovules in axile placentation; style stout, 5-ridged; stigma 5-rayed. Fruit schizocarpic, winged, spinous or tubercled, pubescent, septicidally dehiscent into 5 triangular, indehiscent indurated, transversely locellate (split into secondary cells) 1-seeded mericarps. Seeds exalbuminous, cotyledons ovoid.

30 species

Tribulus terrestris

Tribulus terrestris L., Sp. Pl. 387. 1753; Boiss., Fl. Orient. 1: 902. 1867; Edgeworth & Hook. f. in Hook. f., Fl. Brit. India 1: 423. 1875; Trimen, Handb. Fl. Ceylon 1: 194. 1893; Cooke, Fl. Bomb. Pres. (Reprint ed.) 1: 170. 1958; Tutin in Tutin et al., Fl. Europ. 2: 205. 1968; Nair, Fl. Bashahr Himal.48. 1977; Sharma & Kachroo, Fl. Jammu (Illustr.) 2: t. 46. 1983; Dhaliwal & Sharma, Fl. Kullu Dist. 174. 1999; Kaur & Sharma, Fl. Sirmaur 182. 2004; Singh & Sharma, Fl. Chamba Dist. 206. 2006; Fl. China @ eFloras.org 11: 49; Fl. North Amer. @ eFloras.org vol. 12; Fl. Pak. @ eFloras.org p. 26.

Annual or biennial, prostrate, densely appressed whitish silky pubescent herb. Stem hirsute to setaceous, branches spreading. Leaves sessile or subsessile, paripinnate, 2.5-5 cm long, opposite, one of each alternating smaller; leaflets 3-8 pairs, subsessile, subequal, ovate to elliptic-oblong, 5-10(-12) mm x 3-8 mm, rounded or subcordate at base, apex acute or obtuse, mucronate, margin entire, white and adpressed hairy beneath. Flowers actinomorphic, bisexual, 5-merous, hypogynous, yellow, 6-8 mm long and 1-1.5 cm across, solitary, pseudoaxillary on peduncle shorter than leaves; pedicel up to 1.5(-2) cm long. Sepals 5, free, 5-6 mm x ca. 3 mm, ovate-lanceolate, acute, hairy, persistent. Petals 5, free, spreading, 6-8 mm x 3-4 mm, obovate, obtuse, fugacious. Stamens 10, free, in 2 whorls of 5 each, stamens of outer whorl slightly longer than of inner whorl, antipetalous, stamens of inner whorl alternipetalous; filaments ca. 3-5 mm long; anthers oblong and versatile; each of the inner whorl of 5 stamens subtended adaxially by intrastaminal gland and abaxially by extrastaminal gland. Stamens inserted at base of disc, disc annular and fleshy, lobed. Carpels 5, syncarpous; ovary superior, sessile, hirsute, 5-angled, 5-locular with 3 or 4 ovules per loculus, placentation axile; style stout, 5-ridged, ca. 1.5 mm long; stigma 5-rayed, decurrent (roughly equal branches). Fruit schizocarp, 4-8 mm long, up to 1 cm in diameter, septicidally dehiscent into 5 triangular indehiscent, indurated, transversely locellate (split into secondary cells), 1-seeded mericarps or cocci; mericarps densely pubescent and tuberculate on dorsal side, with 2 (4-6 mm long) patent and 2 short downwardly directed spines (lower 2 may be reduced to tubercles).

Flowering and Fruiting: Almost throughout the year
Common Names: Bullhead, Caltrop, Cat’s Head, Devil’s Eyelashes, Devil’s Thorn, Devil’s Weed, Puncture Plant, Puncture Vine, Tackweed, Tribulus; Gokhru, Tirkundi, Bhakkhra (Hindi)