401. Sclerolepis Cassini, Bull. Sci. Soc. Philom. Paris. 1816: 198. 1816.
Bogbutton [Greek scleros, hard, and lepis, scale, alluding to pappus]
Eric E. Lamont
Perennials, 10–30(–60) cm (rhizomatous; aquatic to subaquatic). Stems decumbent or erect (sometimes floating), simple or branched distal to bases (terete, glabrous; internodes usually shorter than leaves). Leaves cauline; whorled (4–6 per node); sessile; blades 1-nerved, linear, margins entire (apices callus-tipped), faces glabrous or sparsely gland-dotted. Heads discoid, borne singly (peduncles ebracteate). Involucres campanulate to subhemispheric, ca. 10 mm diam. Phyllaries persistent, 22–30+ in 2–3+ series, not notably nerved, linear to broadly lanceolate, unequal to ± equal (glabrous). Receptacles conic or hemispheric, epaleate. Florets ca. 50; corollas pink-lavender to flesh-colored, throats funnelform (sparsely stipitate-glandular), lobes 5, deltate; styles: bases not enlarged, glabrous, branches filiform to linear-clavate. Cypselae prismatic, 5-ribbed, gland-dotted; pappi persistent, of 5 muticous scales. x = 15.
Species 1: e United States.
SELECTED REFERENCES
Crow, G. E. and C. B. Hellquist. 2000. Aquatic and Wetland Plants of Northeastern North America.... 2 vols. Madison. Vol. 1, pp. 414–415. Mehrhoff, L. J. 1983. Sclerolepis uniflora (Compositae) in New England. Rhodora 85: 433–438.
