sow-thistle desert-dandelion

Malacothrix sonchoides (Nutt.) Torr. & A.Gray

Malacothrix sonchoides, known as sow-thistle desert-dandelion, is a flowering plant in the Asteraceae family. It is native to the western United States, including California, Nevada, and Arizona, as well as parts of Mexico like Sonora. The plant grows in sandy soils within habitats such as Joshua tree woodland and creosote bush scrub. It is an annual herb with lemon-yellow corollas and distinctive cypselae with persistent pappi. Chromosome number is 2n = 14.

Description

Malacothrix sonchoides is an annual plant reaching 10-25 cm in height. It has one to five stems that are ascending to erect, typically glabrous, and branched at the base and upper parts. Leaves are narrowly oblong to elliptic, pinnately lobed, and glabrous, with distal leaves reduced and clasping. The involucres are campanulate to hemispheric, and the florets are lemon yellow, with outer ligules exserted 6-10 mm. Cypselae are prismatic, 1.8-3 mm long, with prominent ribs and a persistent pappus. It is adapted to arid environments and is found in sandy substrates across western North America.