| 1. Corollas pale purple; cauline leaves ± deeply lobed |
| C. leucocaulos |
| 1' Corollas yellow to red; cauline leaves toothed to deeply lobed |
| |
| 2. Cauline leaves dentate, weakly spiny; corollas yellow to red; fruit white |
| C. tinctorius |
| 2' Cauline leaves ± deeply lobed, very spiny; corollas yellow; fruit brown |
| |
| 3. Outer phyllaries generally 2 × inner; herbage ± sparsely hairy; stem white |
| C. baeticus |
| 3' Outer phyllaries generally < 1.5 × inner; herbage ± cobwebby; stem straw-colored |
| C. lanatus
|