General: Fiveneedle Pricklyleaf (Thymophylla pentachaeta) is a low-growing, upright subshrub with thin, narrow, lobed green leaves and yellow daisy flowers that appear in the spring and fall. The solitary flowers stand atop a fairly long flowering stalk. Often this compact little shrub stands out as bright green when everything else is brown. After blooming, the leaves fall off and the plant seems to disappear.

Fiveneedle Pricklyleaf is a fairly common component of vegetation communities on well-drained sandy, gravelly, and rocky soils along washes and on upper bajadas and moderate slopes into the lower mountains in the Lower Sonoran (Creosote-Bursage Flats) and Upper Sonoran (Mojave Desert Scrub and Pinyon-Juniper Woodland) life zones.

Family: Sunflower (Asteraceae).

Other Names: Parralena, Five-needle Fetid Marigold, Thymophylla pentachaeta var. belenidium, Dyssodia belenidium, Dyssodia pentachaeta var. belenidium, Dyssodia thurberi

Plant Form: Tiny, upright shrub emerging from a single, stout taproot; stems sweep out and upward.

Height: Usually about ankle high (15 cm).

Bark: Light brown.

Stems: Thin, bending upward.

Leaves: Thread-like and dark green, but deeply divided into several thread-like segments. Immature leaves are unlobed, but the lobes develop as the leaf matures. It can be easier to determine leaf structure from old, dried leaves.

Flowers: Peduncle: (20-100 mm). Inflorescence: single composite flowerhead that stands above the leafy parts. Phyllaries gland dotted. Flowers: disk and ray flowers, yellow, usually about 1/2-inch diameter.

Seeds:

Habitat: Dry, well-drained sandy, gravelly, and rocky soils on upper bajadas and moderate slopes in the lower mountains.

Elevation: About 3,000 to 5,000 feet.

Distribution: California to Texas and south into South America.

Comments: Another rare species of Thymophylla occurs in the Las Vegas area. Pricklyleaf Dogweed (Thymophylla acerosa) looks similar, but the leaf blades are not lobed, and the flowers stand atop a short stalk (0-10 mm). At a casual glance, our common species appears to have non-lobed leaves because the leaves are so deeply incised as to appear as individual, non-lobed leaves. Careful inspection of the leaves with a hand-lens is helpful to confirm the rare species, especially when the flower stalk is short.