Flora of North America species comparison

usually branched proximally, 10–50+ cm.

prostrate to erect, simple or branched.

blades usually appearing terete, 1.5–3(–5) cm, margins often revolute, forming abaxial channel.

opposite or sometimes appearing whorled, bases connate or not, sometimes petiolate or often sessile, stipulate;

stipules ovate or deltate to lanceolate or bristlelike, scarious;

blade subulate or subtriangular to linear and threadlike or spatulate to ovate or orbiculate, seldom succulent.

terminal or axillary cymes, or flowers solitary;

bracts scarious or absent;

involucel bracteoles absent.

erect to ascending, reflexed, secund in fruit.

present or flowers sessile.

sepals 3.5–5 mm;

petals ovate, 3/4–1 times as long as sepals in flower, apex obtuse;

stamens usually 10.

bisexual or rarely unisexual;

perianth and androecium hypogynous or perigynous;

hypanthium absent or dish- or cup-shaped;

sepals 5, distinct or sometimes connate proximally, hooded (Drymaria, Polycarpon) or not, awned (Polycarpon) or not;

petals absent or (3–)5, blade clawed (Drymaria) or not, auricles absent, coronal appendages absent, blade apex entire, erose, or 2(–4)-fid, sometimes emarginate;

stamens (1–)3–5(–10), in 1 or 2 whorls, usually arising from base of ovary or from rim of hypanthium (Spergula, Spergularia);

staminodes absent;

ovary 1-locular;

styles 1 or 3, occasionally 2 or 5, distinct or sometimes connate proximally;

stigmas 3, occasionally 2 or 5.

capsules, opening by 3 or 5, occasionally 4 valves;

carpophore sometimes present.

valves 3.5–5 mm.

sometimes keeled or winged, subglobose, 1–1.1 mm wide, surface minutely roughened or obscurely low-tuberculate (50x), covered with white, club-shaped papillae in part or throughout (packing of seeds in capsule may prevent papillae development in spots), wings white, ± 0.1 mm wide.

3–150+, whitish or tan to often brown or black, ± triangular, pyriform, or reniform to circular, subglobose or laterally compressed to angular (Polycarpon);

embryo peripheral, curved or rarely annular to spirally curved (Spergula).

= [7], 8, 9, (11), 12.

= 18, 36 (both Europe).