Capitula heterogamous bilabiate-inner florets functionally male, outer florets female; corollas bilabiate, in the Flora Zambesiaca area the inner corollas are all equally 2-lipped, while the outer corollas are of 2 kinds, i) 2–3 series of submarginal corollas equally 2-lipped, ii) a marginal series in which the corolla outer lip is strap-shaped (apparently radiate) and the inner lip smaller and 2-lobed (eg. Gerbera, Tab. 9). Occasionally all florets male or all female (plants monoecious or dioecious), or the disk-florets functionally female and the ray-florets functionally male
Style of hermaphrodite or functionally male florets elongating within the anther tube, shallowly to deeply bifid, occasionally undivided in functionally male florets, style arms with stigmatic areas on their inner sides and acute rounded or truncate at the apex, or the arms produced beyond the stigmatic surfaces as triangular, subulate or clavate appendages, variously papillate or hairy, usually with a brush of collecting hairs that sweep the pollen from the anther tube; style of female florets simpler, with acute to rounded style arms and without sweeping hairs
Annual, biennial or perennial herbs (often suffrutescent in the Flora Zambesiaca area with annual leafy stems or scapes from woody rootstocks and/or root tubers), or subshrubs, shrubs, or occasionally scramblers or lianes, sometimes trees, rarely aquatic or epiphytic, sometimes succulent, sometimes spinescent; tissues with schizogenous resin-ducts or articulated lacticifers
Corolla gamopetalous, of(3-)5 united petals, rarely absent; corolla ± regular and (3-)5-lobed (filiform or infundibuliform disk-florets), or bilabiate with a 2-lobed inner lip and a 3-dentate outer lip, or radiate with an abaxial strap-shaped limb (ray) 0–3(4)-dentate at the apex (ray-florets), or ligulate with a strap-shaped limb (ligule) 5-dentate at the apex
Capitula solitary and terminal on scapes or leafy stems, or few to very numerous in lax or ± clustered cymose, often corymbiform synflorescences, occasionally scorpioidly cymose (a reduced cymose arrangement in which the subtending bracts are alternate), or spicate, racemose or paniculate, or aggregated into secondary capitula (glomerules)
Calyx absent, represented by the pappus borne apically on the ovary; pappus consisting of persistent or caducous, 1-many-seriate hairs bristles awns or scales, or pappus elements ± fused to form an annular or ± cup-shaped or ear-shaped corona, or pappus absent; pappus setae barbellate or ± plumose
The floret sexual state, its corolla form, and the combination of floret types on the common receptacle distinguish capitula as follows:Capitula homogamous discoid-all florets of one sexual state, all hermaphrodite (or all female or functionally male); all corollas of the same form and ± regular
Stamens (3-)5, filaments free, inserted on the corolla tube, contractile; anthers introrse, usually apically appendaged, usually laterally connate into a cylinder around the style, thecae rounded sagittate or tailed at the base; pollen usually echinate, sometimes echinolophate or lophate
Flowers (florets) crowded into heads (capitula) surrounded by an involucre of one or more series of free or connate bracts; sometimes the heads compound with the capitula few-or single-flowered; receptacle paleate, setose, pitted or naked, usually convex, sometimes elongated or concave
Capitula heterogamous radiate-central florets hermaphrodite or female or functionally male, outer florets female or neuter, occasionally hermaphrodite; central floret corollas regular, outer or marginal floret corollas radiate, or occasionally bilabiate with a strap-shaped outer lip
Fruit unilocular, 1-seeded, indehiscent (usually an achene), rarely fleshy with the single seed enclosed in a hard endocarp (drupe), sometimes produced apically into a beak (rostrum), crowned by the persistent or caducous pappus, or epappose; endosperm absent or vestigial
Flowers (florets) small, 1–500 or more per capitulum, hermaphrodite or unisexual (female, male or functionally male), or neuter (sterile); ovary inferior, of 2 united carpels, unilocular with 1 erect basal ovule; perianth epigynous
Leaves cauline and alternate or opposite, sometimes whorled, or radical and rosulate, exstipulate or sometimes with stipuliform appendages, sessile or petiolate, usually simple, entire, toothed, lobed or variously dissected
Phyllaries in 2-many series, free and imbricate or ± connate, or sometimes 1-seriate and united or with cohering overlapping margins, persistent or rarely caducous, occasionally accrescent, sometimes apically appendaged
Florets of one or two kinds in each capitulum, hermaphrodite, unisexual or neuter, rarely dioecious, the outer ones often ligulate (ray-florets), the inner ones tubular (disk-florets), or all tubular, or all ligulate
Ovary inferior, 1-locular, 1-ovuled; style of the hermaphrodite or female florets mostly 2-fid, the style-arms smooth, papillose or hairy, tapered, rounded, deltoid or truncate, with or without a terminal appendage
Common receptacle with scales (paleae) or setae subtending the florets, or epaleate and the surface smooth areolate or shallowly to deeply honeycombed (alveolate); alveolae often fimbriate or setose
Capitula heterogamous disciform-florets of 2(3) sexual states, the inner florets hermaphrodite or functionally male and the outer ones filiform and female; all corollas regular
Stamens 5, rarely 4, epipetalous; filaments free; anthers connate into a tube, rarely free, 2-locular, opening lengthwise, often appendaged at the apex and tailed at the base
Inflorescence a capitulum with individual flowers ± sessile and aggregated on a common receptacle and surrounded by an involucre of 1-many series of bracts (phyllaries)
Capitula heterogamous radiant-inner florets hermaphrodite or functionally male, marginal florets larger and neuter; all corollas regular
Corolla sympetalous, 4-5-fid (actinomorphic disk-florets), filiform, ligulate or rarely bilabiate (zygomorphic ray-florets)
Calyx epigynous, reduced to a pappus of persistent or caducous hairs, bristles or scales, or absent
Capitula homogamous ligulate-all florets hermaphrodite; all corollas ligulate
Leaves alternate or opposite, simple or variously divided; stipules absent
Seed without endosperm; embryo straight with plano-convex cotyledons
Herbs, shrubs or rarely small trees or climbers
Fruit (achene) sessile, sometimes beaked
Ovule erect from the base