Herbage glabrous or minutely hispidulous, stipitate-glandular. Leaf blades oblong-obovate, 10-25 mm, margins serrate to lobed (teeth or lobes in 3-5 even pairs, spinulose-aristate). Involucres 5-7 × 4-5 mm. Phyllary apices greenish, spinulose-aristate, densely and promently gland-dotted, glands often coalesced as small resin pockets. Florets 10-13; corollas 4-5 mm. Cypsela ribs not forming apical horns.

Flowering Aug-Oct. Low hills, alkaline and subsaline plains, alkali marshes, stream benches, grasslands, fencelines; of conservation concern; 0-20(-50) m; Calif.

Isocoma arguta is known only from Contra Costa and Solano counties.