Key to the species of Hunzikeria

1. Subshrubs, 40–60 cm tall; petioles 12–23 mm long, blades 16–27 mm wide; corolla limb 38–52 mm wide..................................... .......................................................................................................................................................................... H. gypsophila sp. nov.

- Herbs, woody at the base, 15–20 cm tall; petioles 5–12 mm long, blades 1.5–13 mm wide; corolla limb 16–20 mm wide ............2

2. Leaves up to 40 mm long, blades puberulent adaxially, glabrate abaxially; corolla tube 10 mm long; restricted to Venezuela ......... ................................................................................................................................................................................ H. steyermarkiana

- Leaves up to 20 mm long, blades pilose or glabrate adaxially, puberulent to strigose abaxially; corolla tube 15–25 mm long; distributed from Mexico to southern United States ............................................................................................................................3

3. Peduncles 3 mm long; calyx 4–7 mm long, puberulent; plants from Hidalgo and Querétaro ........................................... H. coulteri

- Peduncles 7 mm long; calyx 10 mm long, pilose; plants from northeastern Mexico and southern United States .............. H. texana