Senna occidentalis is a pantropical plant species.
Vernacular names include ʻauʻaukoʻi in Hawaii, septicweed,coffee senna, coffeeweed, Mogdad coffee, negro-coffee, senna coffee, Stephanie coffee, stinkingweed or styptic weed.
The plant is locally called Bana Chakunda in Odisha, India.
The species was formerly placed in the genus Cassia.
Plant:- Annual undershrub, subglabrous, foetid, few feet high.
Leaves:- Alternate, compound, paripinnate; rachis channelled, presence of a gland at the base of the rachis; stipulate, stipules obliquely cordate, acuminate; leaflets 4–5 pairs, size (3.7 cm X 2 cm- 7 cm X 3.5 cm), obate to oblong- lanceolate; acuminate, margin ciliate, glabrous or pubescence.Inflorescence:- Axillary corymb and terminal panicle.
Flowers:- Complete, bisexual, slightly irregular, zygomorphic, pentamerous, hypogynous, pedicelate; bractate, bracts white with pinkish tinge, thin, ovate- acuminate, caducous; yellow.Calyх:- Sepals 5, gamosepalous, tube short, 5 lobed, obtuse, glabrous, imbricate, odd sepal is anterior.Corolla:- Petals 5, polypetalous, alternisepalous, sub-equal, with distinct claw, conspicuously veined, ascending imbricate, posterior petal is the innermost.Androecium:- Stamens 10, free, unequal in size, 7 perfect and 3 reduced to staminode, filaments unequal, anther dithecous, basifixed, introrse and dehiscing by terminal pores.
Gynoecium:- Carpel 1, ovary superiour, unilocular, many ovuled, marginal placentation; style simple; stigma terminate, capitate.
Fruit:- Pod, dehiscent, woody, 12.5 cm X 0.7 cm, glabrous, recurved, subcompressed, distinctly torulose, 23-30 seeded.