Sowthistle Desertdandelion

Malacothrix sonchoides grows in California in the Mojave Desert (Los Angeles, Kern, San Bernardino, and Riverside counties), the Great Basin Desert (Inyo Mountains), and barely enters the northern margins of the Sonoran Desert. It also grows in the Intermountain Region in Arizona, Colorado, Nevada, New Mexico, Utah, and Wyoming.

Annuals, (5–)10–25(–50) cm. Stems 1–5, ascending to erect, branched near bases and distally, usually glabrous (sometimes glaucous), rarely stipitate-glandular. Cauline leaves: proximal narrowly oblong to elliptic, pinnately lobed (lobes 3–8+ pairs, oblong to triangular, ± equal, apices obtuse to acute), ± fleshy, ultimate margins dentate to denticulate, faces glabrous; distal reduced (narrowly triangular to linear, bases ± dilated, ± clasping). Calyculi of 8–12+, ovate to lanceolate bractlets, hyaline margins 0.05–0.3(–0.7) mm wide, usually glabrous (margins sometimes stipitate-glandular). Involucres ± campanulate to hemispheric, 7–13 × 4–6(–12+) mm. Receptacles bristly. Florets 75–115; corollas lemon yellow, 10–14(–16) mm; outer ligules exserted 6–10(–13) mm. Cypselae ± cylindro-fusiform to prismatic, 1.8–3 mm, ribs extending to apices, ± equal or 5 more prominent than others; pappi persistent, crenate crowns of 15–25+, blunt or rounded teeth. Pollen 70–100% 3-porate. 2. = 14.

Leptoseris sonchoides Nuttall, Trans. Amer. Philos. Soc., n. s. 7: 439. 1841; Malacothrix runcinata A. Nelson

Malacothrix sonchoides is a species of flowering plant in the aster family known by the common names sowthistle desertdandelion and yellow saucers. It is native to much of the western United States, where it grows in sandy substrates in habitat such as Joshua tree woodland, grassland, creosote bush scrub, and ephedra-blackbrush communities.

This species is an annual herb producing one or more hairless, branching stems usually up to about 25 centimeters tall, sometimes approaching 50 centimeters. The fleshy lower leaves have several lobes, while the upper leaves are smaller and simpler. The flower heads contain up to 115 bright yellow florets each just over a centimeter long.