Duration: Annual

Nativity: Native

Lifeform: Forb/Herb

General: Herbaceous annuals, 2-9 cm tall, stems spreading to decumbent and branching from the base, stout, often shiny purple, especially near the base, plants arising from a taproot.

Leaves: Alternate, basal, elliptic to oblanceolate and 5-10 mm long, fleshy, margins entire to scalloped, surfaces hairy, bases narrowed to a wide, short petiole.

Flowers: White with deep purple tips and veins, corollas divided to the base, 2-lipped with 3 erect lobes above (adaxial) lobes ovate, to 0.5 mm long, with glabrous surfaces, the 2 lower (abaxial) lobes oblong, 0.4-0.5 mm long, with acute tips, sepals with the upper and middle sepals linear-elliptic and to 0.7 mm long, the 2 flanking abaxial sepals widely triangular and to 1.4 mm long, filaments declined, fused into a tube around the style tip, 1-1.5 mm long with curved tips and glabrous surfaces, also with a blunt appendage pad of wide cells near the base of the filaments, anthers 0.2-0.3 mm long, stigmas 2-lobed and papillate, ovary inferior in fruit, hypanthium to 1 mm long, subtending bracts of infloresences small and raceme-like with 1 bract per flower, 2-3 mm long and widely elliptic, spreading or reflexed, infloresence axis strongly zigzaged, pedicels thread-like and spreading, 5-12 mm long and to 0.2 mm in diameter, these straight or curving with age.

Fruits: Hemispheric to spindle-shaped (fusiform) capsules, 3-4 mm long, with pointed tips and oblique bases, capsules with 2 chambers. Seeds elliptic, 0.6-0.7 mm long, surfaces with wide zigzag ridges in alternate pitted rows.

Ecology: Found on sand or bare soil, from 700-8,000 ft (213-2438 m); flowering May-June.

Distribution: California, Idaho, Nevada, Oregon.

Notes: This small, reddish-purple stemmed annual enjoys rocky areas, and tends to be small and low-growing. Look to the small white flowers with purplish tips and the small, roundish and small, inflated capsules at stem tips to help identify this species. The fruits often turn very dark in color with age. This species is not currently reported as occurring in Arizona, New Mexico, or Texas, and cannot be found in Kearney and Peebles.

Ethnobotany: Unknown.

Synonyms: None

Editor: LCrumbacher2012

Etymology: Nemacladus comes from the Greek nemos, "thread," and clados, "branch," thus meaning having "thread-like branches", and rigidus means rigid, referring to the stiff leaves.