Petalostigma is a genus of plants under the family Picrodendraceae and the monogeneric subtribe Petalostigmatinae, first defined by von Mueller in 1857. It is native to New Guinea and Australia. In local medicine, pregnancy is said to be avoided by eating the fruit of the quinine bush (Petalostigma pubescens), which does not actually contains quinine. Another example is Petalostigma triloculare which features exploding fruit.