| Besseya alpina | Veronica besseya M.M.Mart.Ort. & Albach subgen. Synthyris |
| Besseya arizonica | Veronica plantaginea E.James subgen. Synthyris |
| Besseya bullii | Veronica bullii (Eaton) M.M.Mart.Ort. & Albach subgen. Synthyris |
| Besseya oblongifolia | Veronica oblongifolia (Pennell) M.M.Mart.Ort. & Albach subgen. Synthyris |
| Besseya plantaginea | Veronica plantaginea E.James subgen. Synthyris |
| Besseya reflexa | Veronica ritteriana (Eastw.) M.M.Mart.Ort. & Albach subgen. Synthyris |
| Besseya ritteriana | Veronica ritteriana (Eastw.) M.M.Mart.Ort. & Albach subgen. Synthyris |
| Besseya rubra | Veronica rubra (Douglas ex Hook.) M.M.Mart.Ort. & Albach subgen. Synthyris |
| Besseya wyomingensis | Veronica wyomingensis (A.Nelson) M.M.Mart.Ort. & Albach subgen. Synthyris |