2. Krigia cespitosa (Raf.) K.L. Chambers ssp. cespitosa (common dwarf dandelion)

Serinia cespitosa Raf.

S. oppositifolia (Raf.) Kuntze (not a valid name)

Pl. 257 f, g; Map 1073

Plants annual, with fibrous roots. Stems 1 to several, 5–45 cm long, erect to loosely ascending, sometimes from a spreading base, with few to several ascending branches, glabrous or rarely sparsely to moderately pubescent toward the branch tips with spreading, gland-tipped hairs, occasionally somewhat glaucous. Leaves basal and alternate along the stems, the uppermost few sometimes appearing opposite, the basal leaves often with short to long, winged petioles, the stem leaves mostly sessile with rounded, clasping bases. Leaf blades 1–15 cm long, linear to narrowly oblanceolate, the first rosette leaves sometimes ovate, entire, wavy, toothed, or shallowly to deeply pinnately lobed, the teeth or lobes spreading, oblong and rounded or triangular and pointed, the leaf tip rounded to more commonly pointed, the surfaces glabrous, occasionally somewhat glaucous. Involucral bracts 4–7(–9), 2–5 mm long, lanceolate to ovate or oblong-ovate, becoming somewhat keeled as the fruits mature, glabrous, persistently scalelike and remaining ascending with age. Ligulate florets 12–25(–35). Corollas 3–7 mm long, light yellow to yellow. Pappus absent. Fruits 1.4–1.7 mm long, narrowly obovoid, more or less circular in cross-section, with usually 15 ribs, these minutely roughened or barbed, reddish brown. 2n=8. April–June.

Scattered, mostly south of the Missouri River (eastern U.S. west to Nebraska and Texas; Mexico). Bottomland prairies, upland prairies, glades, fens, openings of mesic to dry upland forests, and margins of ponds, lakes, and sloughs; also pastures, fallow fields, old fields, banks of ditches, cemeteries, railroads, roadsides, and open, disturbed areas.

Steyermark and other earlier authors used the name Serinia oppositifolia (Raf.) Kuntze for this taxon. Shinners (1947), Vuilleumier (1973), Kim and Turner (1992), and Chambers (2004) all presented evidence that Serinia is merely a specialized kind of Krigia lacking a pappus. Chambers (1973, 2004) further noted that the nomenclatural basis for this name, K. oppositifolia Raf., was not validly published, because Rafinesque did not accept it as a valid name in his own publication. Also, because the species epithet originally was spelled K. cespitosa, the later variant K. caespitosa that is found in some botanical manuals (Barkley, 1986) currently is considered incorrect.

Some populations in Louisiana, Oklahoma, and Texas with slightly larger heads and slightly longer corollas have been called K. gracilis DC., K. cespitosa f. gracilis (DC.) K.-J. Kim, or K. cespitosa ssp. gracilis (DC.) K.L. Chambers.