Sida spinosa L.

Sida species annual, perennial herbs, undershrubs or shrubs. Stems erect or procumbent, stem and branches pubescent with stellate and glandular hairs or glabrous. Leaves alternate, simple rarely lobed, lanceolate-ovate to obovate-elliptic, base obtuse to cuneate, margins entire, serrate-dentate or lobed, apex acute to acuminate, petiolate, stipulate. Inflorescence usually axillary solitary, paired or terminal panicles or racemes, by the reduction of upper leaves. Flowers bisexual, pedicel slender, jointed above the middle, epicalyx absent, calyx 5 lobed or toothed, campanulate or cupular, usually plicate in bud, corolla showy, yellow, cream white, base connate, adnate to stamina column. Staminal column shorter than petals, glabrous or hairy, anthers basifixed, towards apex. Ovary 5-14 carpellate, ovules 1 per locule, style 1 per carpel, stigma capitate. Fruit indehiscent or partly dehiscent by middle dorsal line, rarely by lateral or basal walls when dried, schizocarp, oblate or discoid, minutely pubescent or glabrous, mericarps 5-10, reniform, smooth or reticulate, minutely stellate pubescent. Seed 1 in each mericarp, ovoid to reniform, glabrous or minutely hairy.

Flowering class: Dicot Habit: Shrub

Flowering and fruiting: March-December

Sida species flowers are complete, bisexual, i.e., with functional male (androecium) and female (gynoecium), including stamens, carpels and ovary. Pollination is entomophilous i.e., by insects, or cleistogamy i.e., by self or allogamy i.e., by cross pollination. Flowering/Fruiting: March—December.

Seeds may be dispersed by autochory i.e., self dispersal, anemochory i.e., wind dispersal, zoochory i.e., dispersal by birds or animals, anthropochory i.e., dispersal by humans.

Annual, perennial herbs or undershrubs, about 0.3-1 m tall. Stems erect or diffuse with 1-2 spine like emergences at the petiole bases, stems and branches pubescent with minute stellate hairs, ultimately glabrescent when mature. Leaves alternate, lanceolate-ovate to ovate-oblong, about 6-30 x 5-25 mm across, base obtuse, 3-5 veined, margins crenate-serrate, apex acute to obtuse, sparsely pubescent with minute stellate hairs above and beneath, sometimes glabrescent above, petiole hairy with minute stellate hairs, about 4-25 mm long, stipules linear subulate, filiform, 1 veined, about 3-6 mm long. Inflorescence usually axillary solitary, or 2-5 in terminal clusters, by the reduction of upper leaves. Flowers bisexual, pedicel pilose, jointed above middle, accrescent, about 2-8 mm long, epicalyx absent, calyx 5 lobed or 5 fid, campanulate, about 3-5 mm across, slightly accrescent, lobes triangular, base connate, apex acuminate, glabrous inside, pubescent with stellate and simple hairs inside, about 1 x 2 mm across, corolla showy, yellow, pale yellow, base connate, adnate to stamina column, petals almost or slightly longer than calyx lobes, obovate, margins ciliate, apex shallow emarginate. Staminal column shorter than petals, about 4 mm long, hairy with glandular hairs, anthers basifixed, towards apex. Ovary 5 carpellate, ovoid, about 1.5 mm across, ovules 1 per locule, style 1 per carpel, stigma capitate. Fruit indehiscent or partly dehiscent by middle dorsal line, rarely by lateral or basal walls when dried, schizocarp, oblate or discoid, enclosed by a persistent calyx, minutely pubescent, mericarps 5, reniform, dorsally reticulate, minutely stellate pubescent, about 3-4 mm long, awns about 1-1.5 mm long. Seed 1 in each mericarp, ovoid to reniform, about 1-1.5 mm across, glabrous or minutely hairy near hilium, blackish brown.

Sida species are susceptible to various insect pests, virus and fungi, affecting leaves, fruits and roots.

Notes: Roadsides in grassland or on bunds of fields

Wastelands

Along roadsides and waste places, pantropical.

Not evaluated (IUCN).

Used in Ayurvedic and Unani medicines.