Chamaechaenactis

Rydberg

Bull. Torrey Bot. Club 33: 155. 1906.

Common names: Fullstem
Etymology: Greek, chamae -, creeping, low, on the ground, and generic name Chaenactis
Treatment appears in FNA Volume 21. Treatment on page 395. Mentioned on page 364, 366.

Perennials, 2–7(–9) cm (to 10–20+ cm across). Stems mostly subterranean (caudices relatively thick, branched; aerial stems essentially peduncles). Leaves mostly basal; alternate; petiolate; blades (1- or 3-nerved) cordate, elliptic, ovate, or rounded, margins entire or distally ± crenate, revolute to ± plane, faces ± strigose and gland-dotted, adaxial sometimes glabrescent. Heads discoid, borne singly. Involucres ± obconic, 6–15 (10–23 pressed) mm diam. Phyllaries 11–15 in 2 series (± erect, sometimes spreading in senescence, oblong to oblanceolate, ± unequal, herbaceous, abaxially densely villous, obscurely glandular). Receptacles convex, knobby, epaleate. Ray florets 0. Disc florets 10–30+, bisexual, fertile; corollas white to pinkish, tubes shorter than ± cylindric throats, lobes 5, ± deltate (style branches stigmatic in 2 lines, appendages linear-oblong, blunt). Cypselae clavate, ± quadrangular with 8–12 obscure nerves, densely piloso-strigose, eglandular; pappi persistent, of 7–11, (distinct) oblanceolate to narrowly spatulate, erose scales in 2 series (midnerves prominent). x = 16.

Distribution

w North America.

Discussion

Species 1.

Chamaechaenactis has been considered a close relative of Chaenactis, which has superficially similar heads. Nuclear rDNA evidence (B. G. Baldwin et al. 2002) suggests closer relationship to Bartlettia, Hymenopappus, and other members of Bahiinae sensu Baldwin. Such a placement was also suggested by Rydberg when he segregated Chamaechaenactis from Chaenactis.

... more about "Chamaechaenactis"
James D. Morefield +
Rydberg +
Fullstem +
w North America. +
Greek, chamae -, creeping, low, on the ground, and generic name Chaenactis +
Bull. Torrey Bot. Club +
preece1953a +
Undefined (tribe Undefined) subtribe Bahiinae +  and Undefined (tribe Undefined) subtribe Palafoxiinae +
Chamaechaenactis +
Asteraceae (tribe Heliantheae) subtribe Chaenactidinae +