Flora of North America species comparison

usually erect, branched distally or throughout, (leafy).

basal and/or cauline; alternate; ± petiolate or sessile; (leaf bases often decurrent on stems) margins usually lobed to dissected, sometimes dentate or entire (usually spiny).

basal and cauline or all cauline;

basal and proximal cauline winged-petiolate, distal cauline sessile, sometimes clasping;

blade margins dentate to pinnately lobed, ± spiny, faces glabrous or ± glandlar and/or ± tomentose.

ovoid, constricted distally.

flat to convex, usually epaleate (often pitted and often bristly-setose or densely hairy).

convex to conic, epaleate, bearing subulate scales.

15–60+;

corollas yellow to red or ± purple, tubes very slender, throats gradually or abruptly expanded, ± cylindric or short-campanulate, lobes linear;

anther bases short-tailed, apical appendages oblong;

style branches: fused portions with slightly swollen basal nodes minutely hairy, distally minutely papillate, distinct portions very short.

0 (corollas of peripheral florets in radiant heads often notably enlarged, usually 5-lobed, sometimes zygomorphic and raylike or ± 2-lipped).

0 or (in disciform heads) in 1–3+ series;

corollas (usually present) usually yellow, sometimes ochroleucous or cyanic.

bisexual and fertile (rarely functionally staminate);

corollas yellow, cyanic, or white, usually actinomorphic, lobes 5, usually narrowly triangular to ± linear, seldom deltate (sometimes unequal, corollas then ± zygomorphic);

anther bases ± tailed, apical appendages usually oblong (filaments sometimes papillate to pilose; connate in Silybum);

styles (bisexual, fertile florets) distally enlarged or swollen, usually dilated and/or with rings of hairs at or near point of bifurcation, abaxially smooth or papillate to hairy (at least distally, sometimes ± throughout), “branches” often connate, adaxially continuously stigmatic ± to tips, apices rounded to acute, appendages essentially none.

usually persistent [readily falling], in (1–)3–5+ series, usually distinct, usually unequal, usually herbaceous (sometimes fleshy), margins (entire or denticulate to pectinate, sometimes spiny) and apices seldom notably scarious (apices often spinose or ± expanded into distinct, often fimbriate-fringed, pectinate, and/or spiny appendages).

many in 4–5 series, linear to ovate (at least outer ± leaflike), bases appressed, apical appendages more herbaceous, prominently veiny, spiny-dentate or -lobed, spine-tipped.

0 (involucres sometimes closely subtended by leaflike peduncle bracts).

mostly homogamous (usually discoid, sometimes disciform or radiant, then peripheral florets usually pistillate or neuter, sometimes bisexual or with staminodes), borne singly or in corymbiform, paniculiform, or racemiform arrays (heads with 1 floret each aggregated into second-order heads in Echinops).

discoid, borne singly or in few-headed cymiform arrays.

usually monomorphic within heads (often thick-walled, hard, nutlike, receptacular attachments basal or lateral, bases sometimes each with an elaiosome), usually ellipsoid, obovoid, or ovoid, sometimes rounded-prismatic, terete, 4–5-angled, or ± compressed, rarely beaked, bodies usually smooth, sometimes rugose or 10- or 20-nerved (glabrous or puberulent to villous; often with apical umbo and/or crown in addition to pappus);

pappi (rarely 0) readily falling or persistent, usually of fine to coarse, barbellate to plumose bristles, sometimes of scales, sometimes both bristles and scales.

oblong to obpyramidal, ± 4-angled, apices with smooth or dentate rims, faces usually ± roughened (outer) or smooth (inner), glabrous, attachment scars lateral;

pappi 0 or (usually only inner cypselae) ± persistent, of many, usually unequal, narrow scales overlapping in several series.

= 10, 12.