Plant: shrub or subshrub; to 0.5 m tall, often less; current growth often sparsely branched

Leaves: sessile, 1-3(-4) cm long, 0.2-1 cm wide, those of branches and main axis similar in size; blade linear to narrowly oblong or elliptic; margin entire, occasionally few-toothed

INFLORESCENCE: RACEMES to 10(-20) cm long, 1-2 cm wide. OUTER BRACT 5-11 mm long, 2-7 mm wide; margin crenate to entire; apex obtuse

Flowers: petals free, 2-5.5 mm long; stamens 3-7 mm long

Fruit: ACHENE 2-4 mm long; SEED subapical; testa non-sculptured; endosperm lacking

Misc: Rocky canyons to sandy washes and dunes; to ca. 1000 m (3200 ft); (Dec)Mar-Jun

REFERENCES: Christy, Charlotte M. 1998. Loasaceae. J. Ariz. - Nev. Acad. Sci. 30(2): 96.

Duration: Perennial

Nativity: Native

Lifeform: Subshrub

General: Herbaceous or shrubby perennials, to 50 cm tall, stems current growth often sparsely branched, herbage with minutely barbed hairs.

Leaves: Alternate, sessile or nearly so, linear to narrowly oblanceolate, to 25 mm long and 3-6 mm wide, with obtuse to acute tips, margins entire to irregularly toothed, surfaces with barbed hairs.

Flowers: White, with 5 free petals 2-5.5 mm long, sepals 5, stamens slightly exserted, 3-7 mm long, styles 3-6 mm long, ovary inferior, flowers with 3 subtending ovate-cordate outer bracts 5-11 mm long, 2-7 mm wide the outer larger than the inner, with obtuse tips and crenate to entire margins, densely soft-pubescent, flowers borne in racemes to 20 cm long and 1-2 cm wide on pedicels 1-2 mm long.

Fruits: Erect, appressed, ovoid, papery, achenes 2-4 mm long. Seeds 1 per achene, fusiform, 1.5-2.5 mm long, with smooth surfaces, somewhat visible through the outer surface of the achenes.

Ecology: Found in rocky canyons, sandy washes and dunes, to 3,500 ft (1067 m); flowering December-June.

Distribution: Arizona, California; Mexico.

Notes: This small plant tends to grow in dense clumps, with thick masses of small leaves and tightly bunched infloresences, the fruits with wide, papery margins and noticable endosperm. Look for it in Yuma county and southwestern Arizona according to Kearney and Peebles.

Ethnobotany: Unknown.

Synonyms: None

Editor: LCrumbacher2012

Etymology: Petalonyx comes from the Greek petalon, "petal," and onyx, "claw," thus claw-petalled, and linearis means linear, parallel-sided.