What is a genus of tropical apocynaceous shrubs having singularly twisted flowers. One species (Strophanthus hispidus) is used medicinally as a cardiac sedative and stimulant called?

strophanthus — A genus of tropical apocynaceous shrubs having singularly twisted flowers. One species (Strophanthus hispidus) is used medicinally as a cardiac sedative and stimulant. (Webster's 1913.)

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