Annuals, to 28 cm. Stems erect, branched distally, glabrous or ± hairy. Leaves linear, 10-80 × 1-2(-3+) mm, margins entire, faces glabrous or sparsely hairy. Involucres hemispheric, 5-7 mm. Phyllaries 8-14, ± deltate (distinct tips ± deltate), glabrous but for apices. Receptacles ± conic, warty, glabrous or sparsely hairy. Ray florets 6-10; (corollas lemon- or golden yellow) laminae narrowly oblong, 6-7 mm. Anther appendages deltate or broadly ovate. Cypselae black, strongly flattened, obovoid, 2-3 mm, margins ciliate (hairs white or stramineous, stiff, blunt, curved), faces glabrous or scabrous; pappi 0. 2n = 14.

Flowering Feb-Apr. Vernal pools and wet alkali flats; 0-100 m; Calif.

Lasthenia chrysantha has the narrowest ecologic range within Lasthenia sect. Hologymne and is mostly limited to alkali flats in the San Joaquin Valley.