Krigia cespitosa (Raf.) K. L. Chambers (forma gracilis), opposite–leaved dwarf dandelion. Annual, taprooted, rosetted, several–stemmed at base, with ascending to suberect inflorescences, in range < 25 cm tall; shoots with mostly basal and some cauline leaves, basal leaves mostly withered and broken at flowering, vegetative tissues glabrous; latex milky.
Stems cylindric, to 2 mm diameter, tinged reddish, smooth with scattered glandular hairs.
Leaves helically alternate (basal leaves) and opposite (cauline leaves), simple sometimes coarsely lobed (basal leaves), petiolate, without stipules; petiole of basal leaf 1/2 sheathing stem, thin and winged, indistinct from blade; oblong to narrowly oblong folded upward from midrib, to 100 mm long, winglike at stem to 4 mm wide, deeply lobed (basal leaves) to shallowly lobes and dentate on margins, acute at tip, pinnately veined with midrib strongly raised on lower surface.
Inflorescence heads, in cymelike array, head ligulate, to 26–flowered, bracteate; peduncle cylindric, having conspicuous, radiating, long glandular hairs with yellowish heads (to 0.8 mm long) especially approaching involucre; involucre bell–shaped, 2.5—3 mm diameter, phyllaries 5—8 in 1 series, fused at bases and overlapping, acuminate–ovate, 5—6 × 1.4—2.1 mm long, green with narrow colorless membranous margins, somewhat glaucous, rounded on back below midpoint, glabrous and lacking glandular hairs; receptacle hemispheroid, 2 mm across, lacking bractlets (paleae), glabrous.
Ligulate flower bilateral, ca. 2 mm across; calyx (pappus) absent (inconspicuous vestigial ring); corolla 5–lobed, 3.5—5 mm long, before anthesis inrolled as cylinder; tube narrowly funnel–shaped, 0.7 × 0.7 mm, colorless, with colorless papillate hairs; limb yellow, lobes (teeth) triangular, 0.5—0.6 × 0.35—0.4 mm; stamens 5, attached to top of corolla tube; filaments 0.7 mm long, whitish; anthers fused into cylinder surrounding style, basifixed, dithecal, ± 1 mm long, yellow longitudinally dehiscent; pollen light yellow; pistil 1; ovary inferior, obovoid, 0.6—0.7 mm long, green, ± 15–ribbed, 1–chambered with 1 ovule; style 2.5—2.8 mm long, yellow, minutely barbed above midpoint, 2–branched near tip.
Fruits cypselae (achenes), obovoid truncate at top, 1.5—1.8 × 0.8—0.9 mm, brown to reddish brown, with ± 15 lengthwise ribs and 5 dimples near base, the ribs regularly and finely cut horizontally and shallowly cut in furrows; pappus absent (inconspicuous vestigial ring).
A. C. Gibson