Small succulent herb forming extensive patches; stems prostrate, rooting at nodes; branches ascending, up to 15 cm. or more long, us. reddish, succulent; internodes up to 2 cm. long. Lvs (4)-5-10 mm. long, thick, fleshy, narrow-oblong to oblong-spathulate, obtuse. Fls 4-5 mm. diam.; peduncles 3-4 mm. long; calyx deeply obtusely lobed; petals white, > calyx, oblong, broadly obtuse. Scales 4, ± stipitate, linear-cuneate, truncate. Carpels turgid; style very short, recurved; seeds 6-8-(10) per carpel.

2n = 28

Perennial herb forming small to very large and extensive loose or dense mats, sometimes to many m diam.; stems decumbent, rooting at nodes, ascending at tips, much-branched. Lvs connate at base, very variable, 2-12 × 1.2-3.4 mm, c. 0.7 mm thick, narrowly oblong-spathulate or narrowly oblong-elliptic, sometimes elliptic, flattened above, weakly convex beneath; apex obtuse. Fls solitary in lf axils, star-like, 4-merous, 4-6 mm diam.; pedicels 1-3 mm long at anthesis, not elongating at fruiting. Calyx lobes 1-1.8 × 0.5-0.6 mm, ovate or triangular-ovate, obtuse. Petals 2-3.5 × 1.2-1.7 mm, broadly obovate-elliptic to suborbicular, white or white with pink flush towards base, obtuse, much > calyx. Scales 0.8-0.9 mm long, oblong-cuneate to almost linear and only slightly wider towards apex. Follicles smooth. Seeds 0.5-0.7 mm long.