What is "phemeranthus"

Phemeranthus (Fameflower) is a genus of flowering plants in the miner's lettuce family, Montiaceae, native to the Americas. It is sometimes placed in Portulacaceae. The name is derived from the Greek words εφήμερος (ephemeros), meaning "living for one day," and ἄνθος (anthos), meaning "flower." Common names for the various species are often fame flower, rock rose, rock pink, and sand pink.