Flora of North America species comparison

sprawling t2o erect, nearly simple to much-branched especially distally, 7–35 cm, retrorsely pubescent on 1 side or throughout.

prostrate to ascending or erect, simple or branched.

stipules lanceolate to ovate, 5–10 mm, apex acuminate, entire;

blade linear-oblong to oblanceolate, 5–30 × 1–7 mm, leathery, apex acute to cuspidate, moderately antrorsely pubescent.

opposite, distalmost or all sometimes alternate, bases connate or not, sometimes petiolate, stipulate;

stipules ovate or deltate to lanceolate or spatulate, scarious;

blade needlelike or often spatulate to elliptic or suborbiculate, seldom succulent.

terminal or axillary cymes or flowers solitary;

bracts foliaceous or usually scarious;

involucel bracteoles absent.

present or flowers sessile.

5-merous, ± short-campanulate, with prominently enlarged hypanthium and calyx flaring distally, (1.5–)2–2.3 mm, pubescent proximally with short, hooked hairs;

sepals greenish to brownish or red-brown, white distally, veins absent, oblong to obovate, 1–1.5 mm, leathery to rigid, margins white, 0.2–0.3 mm wide, papery, apex terminating in divergent awn, hood broadly rounded, awn white, stout-conic, 0.5–0.6 mm, glabrous;

staminodes filiform, ± 0.3 mm;

style 1, cleft in distal 1/5, 0.3–0.6 mm.

bisexual or sometimes unisexual (the plant then dioecious or polygamodioecious);

perianth and androecium perigynous;

hypanthium usually cup-shaped or cylindric or conic to urceolate;

sepals (3–)5, distinct or rarely connate proximally, apex often hooded or awned (awn often subapical);

petals absent;

stamens absent or 1–5, in 1 whorl arising from hypanthium rim;

staminodes absent or 5 (16–19 in Achyronychia);

ovary 1-locular;

styles 1–3, distinct or sometimes connate proximally;

stigmas 2 or 3.

utricles, indehiscent or sometimes opening by 3 or 8–10 valves;

carpophore absent.

1, white to tan or brown to black, ovoid to reniform, not or slightly laterally compressed;

embryo peripheral or central, curved or straight.

terminal, 25+-flowered, much-branched but congested, clusters 5–20 mm wide.

ellipsoid to subglobose, 0.5–0.8 mm, minutely papillate distally.

= 7, 8, 9.