Pentachaeta exilis
Proc. Amer. Acad. Arts 8: 633. 1873.
Plants 2–6 cm. Stems simple or branched, rarely with many branches from bases. Leaf-blades linear to filiform, 12–32 × 0.5–1 mm. Involucres turbinate to campanulate. Phyllaries in 2 (–3) series, elliptic to obovate, glabrous or sparsely and minutely glandular. Ray (or pistillate) florets 0 or 1–5; corollas white, laminae 0.8–2 mm, or 0, or apiculum 0.1–0.5 (–1) mm. Disc-florets 3–6 (–15); corollas yellowish to reddish, club-shaped, widened through limbs, abruptly contracted at lobes, lobes 5, (lobes and sometimes distalmost portion of limbs) yellow or purplish red at maturity, style-branches (0.7–) 1–2 mm, stigmatic portions 0.4–0.5 mm. Pappi 0, or of (3–) 5 bristles, not dilated at bases. 2n = 18.
Discussion
Subspecies 2 (2 in the flora).
Plants of Pentachaeta exilis with greatly reduced or completely absent pappi apparently are scattered over the range of the species. This feature is relatively constant within a population.
Selected References
None.
Key
| 1 | Ray (pistillate) corollas elaminate or with apiculum 0.1–0.5(–1) mm; disc florets 3–6(–15), corolla lobes red-purple, style branches (0.7–)1–2 mm, stigmatic portions 0.4–0.5 mm | Pentachaeta exilis subsp. exilis |
| 1 | Ray (pistillate) corollas laminate, laminae 0.8–2 mm; disc florets (7–)15–34, corolla lobes yellow, style branches 2–3 mm, stigmatic portions 0.6–1mm | Pentachaeta exilis subsp. aeolica |
"widened" is not a number.