Polygala lindheimeri A. Gray var. parviflora Wheelock, rock milkwort. Perennial herb, several—many–stemmed at base, not rosetted, principal shoots ascending, in range < 20 cm tall; shoots with only cauline leaves.
Stems ± cylindric, to 1 mm diameter, green, short–hairy (puberulent) with numerous upward–arching hairs.
Leaves helically alternate, simple, short–petiolate, without stipules; petiole hemicylindric, < 0.8 mm long, light green; blade lanceolate–linear to narrowly elliptic–linear, < 10—25 × 1.5—3 mm, tapered at base, entire, acute at tip, 1–veined with midrib visible and slightly raised on lower surface, lower surface sparsely short–hairy.
Inflorescence raceme, terminal (paired at fork with new axillary shoot), several—15+–flowered, bracteate, short–hairy with upward–arching hairs; peduncle cylindric or broadly 1–ridged (ridge descending from the lowest bractlet), 0.5 mm diameter; rachis ± zigzagged, internodes to 8 mm long, often with ridge descending from bractlet; bractlet subtending pedicel, cupped–ovate, 0.8—1 mm long, margins and tip often purple, short–hairy on lower surface, persistent; bracteoles 2 at base of pedicel, opposite, lateral to bractlet and spreading, short–oblong, < 0.6 × 0.2—0.25 mm, < bractlet, margins and tip often purple, short–hairy on lower surface, persistent; pedicel cylindric, 1.5—2.5 mm long, green or with light purple
Flower bisexual, bilateral, ca. 4 mm across, 6 mm long; sepals 5, heteromorphic; upper sepal boat–shaped, 3 mm long, green with purple with pale pink membranous margins, short–hairy on outer (lower) surface, persistent and often aging keeled and folded; lateral 2 sepals petal–like, obovate, 4.5—5 × 2.2—2.5 mm, green and pale pink at base becoming rose or light pink–purple approaching to tip, with reddish midvein visible above midpoint and short–hairy on outer (lower) surface; lower 2 sepals, ovate, ca. 2 × 1 mm, green and purple with pale pink membranous margins; nectary small protrusion of reception, at base of upper sepal; petals 5 (appearing as 3), dimorphic; upper 2 petals. ca. 4.5 mm long, whitish and fused to staminal tissue below midpoint on lower margin, free and inrolled on upper margin, the lobes with green and pink–purple tips; lateral 2 petals fused with and indistinct from staminal tissue; lower petal highly modified above midpoint expanded into pouch containing stigma and anthers, the pouch 2 × 1.5 mm, pinkish purple and white but part of upper margin green, pouch with greenish projection 1 mm long exserted from flower; stamens 7—8, fused at base to form a sheet, enveloping ovary and lower style, ca. 2.5 mm long, mostly white, opened along upper side and constricted at tip, glabrous; free filaments to 1 mm long, white, strongly curved upward and surrounding upper style; anthers basifixed, appearing monothecal, 0.2—0.3 mm long, orange–yellow, dehiscent at tip; pollen yellowish; pistil 1, ca. 4 mm long (unstraightened), short–stalked (stipe), stipe to 0.4 mm long, green, glabrous; ovary superior, roundish and flat, 1.5 mm long, green, densely short–hairy, 2–chambered, each chamber with 1 ovule attached to center near top; style included, strongly bent within corolla pouch, straight portion whitish, upward portion flared and green, 1.3 mm long, at tip with concave and oblique stigma 0.6 mm across.
Fruit capsule, loculicidal, 1—2–seeded, dehiscent by 2–valved, roundish and strongly flattened, 3.5—4 mm.
Seed with aril, aril birdheadlike (side view), with aril 3 mm long; seed oblong, 2.5 × 1.2 mm, densely covered with descending, hirsute white hairs; aril firmly attached near hilum, fleshy, to 1.5 mm long, whitish, with 2 descending flaps (lobes).
A. C. Gibson