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.
ACANTHOLIMON
General description:- Spiny, cushion-forming shrubs.
Leaves:- Alternate, simple.
Flowers:- Inflorescence of 3-bracteate, 1-flowered spikelets grouped into a simple, spike-like panicle. Calyx funnel-shaped (infundibuliform); tube slender and 10-ribbed at base; limb thin and dry (scarious), pleated (plicate), shortly 5-dentate, with slightly excurrent ribs. Petals united (connate) at the base. Stamens free. Styles 5; stigmas capitate.
Fruit:- Indehiscent.
Key features:-
1) Stems leafy.
2) Leaves pungent.
3) Stigmas capitate.
4) Fruit indehiscent.
LIMONIASTRUM
General description:- Perennial, rarely annual, dwarf shrubs.
Leaves:- Simple, usually in a basal rosette, but densely leafy branches sometimes present; leaves often absent when in full flower (anthesis).
Flowers:- Inflorescence a corymbose panicle, with terminal, secund spikes, often with non-flowering branches, usually with a reddish scale at the base of each branch. Spikes of 3-bracteate, 1- to 5-flowered spikelets; inner and outer bracts external to the spikelet, the middle one internal and often inconspicuous. Calyx funnel-shaped (infundibuliform); limb scarious, usually coloured, sometimes shortly dentate between the lobes. Corolla-tube about as long as the lobes, or the petals connate only at the base. Stamens inserted at the base of the corolla. Styles 5, glabrous, connate in basal half; stigmas thread-like (filiform).
Fruit:-
1) Calyx infundibuliform.
2) Stamens inserted in base of corolla.
3) Styles 5, free or connate in basal half;
4) Fruit circumscissile towards apex or with irregular dehiscence.
5) Corolla-tube about as long as lobes.
6) Spikes secund, the terminal not distinctly larger.
7) Stigmas filiform.
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.