General description:- Herbs or shrubs.
Leaves:- Alternate or in basal rosettes, exstipulate.
Flowers:- Inflorescence usually cymose, often contracted into a capitulum, rarely spike-like. Flowers actinomorphic, 5-merous, usually in bracteate spikelets. Calyx tubular below, toothed (dentate) or lobed and at least slightly thin and dry (scarious) and often pleated (plicate) distally, persistent. Petals united (connate) only at the base, or the corolla with a usually short tube. Stamens united with the petals (epipetalous). Styles 5, or 1 with 5 stigma-lobes. Ovary superior, 1-locular.
Fruit:- Dry, membranous, 1-seeded, surrounded by calyx, not splitting open to release their seeds (indehiscent) or with circumscissile or irregular dehiscence.
PLUMBAGO
General description:- Shrubs or perennial herbs.
Leaves:- Alternate, simple.
Flowers:- Inflorescence of (2-)3-bracteate, 1-flowered spikelets grouped into terminal spikes. Calyx tubular, 5-ribbed, scarious; limb deeply 5-dentate. Corolla with narrow tube and rotate limb. Stamens free. Style 1, with 5 stigma-lobes.
Fruit:- Circumscissile near base, dehiscing upwards into 5 valves.
Key Features;-
1) Leaves not pungent; stigmas filiform or lobed; fruit dehiscent.
2) Calyx tubular; stamens free; style 1; fruit circum-scissile near base, dehiscing upwards by 5 valves.
3) Leaves auriculate-amplexicaul; corolla with narrow tube and rotate limb.