Stems mostly reddish; sepals acute, often with puple coloring, persistent in fruit; petals white to pale pink, five; stamens yellowish or matching petal color, 5 (rarely to 10); flowers open in afternoon; fruit are pointed apically and three-angled, not affected by internal pressure from seeds, self dehiscent with valves persistent until disturbed; seeds nearly smooth; only vary rarely over calcareus substrates, then in organic accumulations.