Shrub to 3 m tall. Leaves mostly 5-12 cm long, more or less oblong, pointed, glossy above. Flower cluster terminal or axillary. Flowers purple with a white eye, the tube 3-4 cm long. [B. calycina Benth., B. eximia (Schiedw.)]
B. eximia (Schiedw.) Bosse is a name that refers to a more compact floriferous variant of B. pauciflora and is sometimes used as a cultivar name.
B. americana L., Lady of the Night, from the WIndies is a summer-flowering shrub to 4 m or so tall. Leaves elliptic to obovate, mostly 5-10 cm long, 2-5 cm wide, papery. Calyx about 5 mm long in flower, the floral tube 4-7 cm long.
B. latifolia (Pohl) Benth. has leaves mostly more than 12 cm long and flowers violet with a white eye, fading with age; late winter to early spring.
Also occasionally available are B. undulata Sw., Rain Tree, from Jamaica, which has wavy white flowers yellowing with age and B. uniflora (Pohl) D. Don from South America, which has blue-violet flowers with a distinctive yellow throat.
Source: (2002). Solanaceae. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.