Leaf blades (proximal) 3-10 cm × 2-8 mm. Phyllaries 3-5 mm. Disc corollas 3-4.5 mm. Cypselae 2.5-3.5 mm. 2n = 28. Flowering Jun-Oct. Banks and dry beds of streams and pools, often in rocky sites or alkaline clays; 30-600 m; Calif. Holozonia filipes is the only perennial, continental tarweed with white corollas or filiform peduncles and is unique among the perennials for occurring in low-elevation, summer-hot, interior habitats. Like most of the perennial, continental tarweeds, H. filipes is self-incompatible and has a geographic distribution marked by major disjunctions between some populations.