Flora of North America species comparison

fibrous.

prostrate to erect, forming mats; rooting at nodes in some species.

cauline, opposite, those of each pair equal;

stipules absent;

petiole bases clasping to ± connate, ± widened, margins usually scarious;

blade usually flat, linear to spatulate or ovate, tapered, margins entire.

axillary, flowers solitary or in cymes, sessile or pedicellate;

bracts absent or 2.

hypanthium obconic;

calyx lobes 5, reddish adaxially, usually hooded near tip;

petals and petaloid staminodia absent;

stamens [1–]5–30, often connate proximally;

pistil 2–5-carpellate;

ovary half inferior, 2–5-loculed;

placentation axile;

ovules to 60;

styles 2–5, papillate;

stigmas 2–5.

capsules, ovoid to obconic, dehiscence circumscissile.

to 60, black to brown, arillate, usually reniform, shiny or dull, smooth or rugose.