Comprehensive DescriptionRead full entry
DescriptionDecumbent epilithic herbs rooting at proximal nodes, prostrate portions 5–20 cm long, with short internodes, mostly glabrous, ascending portions 15–30 cm tall, with few small hairs, with long basal internodes; stems narrowly fistulose. Leaves (Fig. 1A) opposite, petioles mostly 3–5 mm; blades deltate in outline, mostly 4–7 mm long and wide, 3-7-lobed with sinuses 1/3-1/2 to midvein, basal margin truncate or subtruncate, triplinervate at base, margins of lobes often slightly notched, sparsely pilose adaxially, paler and hairless with crowded glandular dots abaxially. Inflorescence (Fig. 1B) terminal on ascending portions, ascending parts not branched below, distally loosely branching with 3–10 capitula, with few minute opposite to subopposite bracteoles; peduncles mostly 0.5–1.8 cm long. Capitula discoid, broadly hemispherical, to 7 mm high and wide; involucres (Fig. 1C) eximbricate; bracts c. 16 in mostly 2 series, subequal, obovate, with obtuse to rounded tips, chartaceous-becoming more scarious distally, bicostate proximally, few shorter outer bracts, scarcely spreading at maturity, essentially glabrous; receptacle (Fig. 1C) high-conical, fistulose, epaleate, without evidence of fully developed florets born on distal part. Florets 20–23; corollas white, 2.2–2.3 mm long, mostly glabrous, sparse glandular dots on lobes, immediate base dilated, thickly ribbed, narrowed to a slender tube closely investing the style, limb abruptly ampliate, campanulate, lobes (Fig. 1D) deltate, with intermarginal ribs, cells projecting at distal ends on inner and outer surface; anther collars slender, with numerous annular thickenings that do not completely obscure transverse cell walls; anther thecae (Fig. 1E) c. 0.5 mm long; apical appendage slightly broader than long. Style base without expanded node, papillae or hairs, style appendages thickened, densely papillose. Cypsela (Fig. 2) 1.2–1.3 mm long, somewhat fusiform, 3–5 costate, with few scabrae on ribs; carpopodium (Fig. 1F) broadened, with distinct projecting upper rim, cells enlarged and elongate with moderately thickened walls; pappus iniserate (Fig. 2) with c. 10 persistent capillary bristles, reaching to approximately the base of corolla lobes, broadened but not contiguous at base, scabridulous, narrowed to apex. Pollen c. 18 μm in diam. in fluid.