Justicia longii

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Justicia longii, or the longflower-tube tongue, is a herb-like perennial shrub in the acanthus family (Acanthaceae). It grows in the Arizona Upland area of the Sonoran Desert. Each white flower opens in the evening and lasts only one night; by morning the petals have fallen, leaving a white carpet on the ground. It blooms from April to October. The species also grows in the Sierra de La Libertad in central Baja California and in Sonora, Mexico.