| Sometimes they are umbilicate below, so that a vertical section would be obcordate. |
| Owing to the rotation of the posterior loph, the apex of the obcordate tooth is at its lingual side. |
| The most remarkable modification of M3 in Cratogeomys is the obcordate pattern developed in P. merriami of the castanops-group. |
| The flowers have bright yellow petals which are obovate or obcordate and from 4-6 mm long. |
| They all have ternate leaves with obcordate leaflets, and with the exception of O. violacea, bear yellow flowers. |
| There are fine, spreading hairs on the leafstalks, and the leaflets are obcordate and toothed. |
