Galphimia gracilis, a species in the genus Galphimia of the family Malpighiaceae, is native to eastern Mexico. It is widely cultivated in warm regions throughout the world, often under the common names gold shower or shower-of-gold or sometimes thryallis. In horticultural publications, in the nursery trade, and on websites, this species is commonly but mistakenly referred to as Galphimia glauca, Galphimia brasiliensis, Thryallis glauca, Thryallis gracilis, or (often in South America) Thryallis brasiliensis.
Galphimia gracilis is easily told apart from the true G. glauca and G. brasiliensis by the flowers. In G. gracilis the petals fall as the fruit matures; in G. glauca the petals are persistent even in fruit. In G. gracilis many flowers of a dense inflorescence are open at one time, and the petals (claw and limb) are 8–14 mm long and 4–8 mm wide; in G. brasiliensis only 2 or 3 small flowers are open at one time on a sparse inflorescence, and the petals are only 4–5 mm long and ca. 3 mm wide.