| Code | Definition | Number of Accessions |
| CYL | Cylindrical-columnar shaped pollen - Medicago rigidula type | 109 |
| INT | Intermediate shaped pollen, possible species hybrid between rigidula and rigiduloides | 5 |
| IRR | Irregular triangular-pyramidal shaped pollen - Medicago rigiduloides type (irregular) | 2 |
| MIX | Some plants rigidula type and some plants rigiduloides type within the same accession | 5 |
| TRI | Triangular-pyramidal shaped pollen - Medicago rigiduloides type | 190 |