Table 5.
Key to Iberian Peninsula and the Balearic Islands species of Orobanche based on seed features
| 1. | Epidermal seed coat cells with smooth outer periclinal walls | 2 |
| 1′. | Epidermal seed coat cells with fibrillar outer periclinal walls | 20 |
| 2. | Outer periclinal walls impede vision of inner ones; anticlinal walls thickening at the vertices | O. rapum‐genisteae |
| 2′. | Outer periclinal walls allow vision of inner ones; anticlinal walls of even or uneven thickness | 3 |
| 3. | Epidermal seed coat cells with perforate inner periclinal wall | 4 |
| 3′. | Epidermal seed coat cells with rugulose or granulate inner periclinal wall | 18 |
| 4. | Cells of inner periclinal wall with a small central mammilla | 5 |
| 4′. | Cells of inner periclinal wall without a central mammilla | 6 |
| 5. | Anticlinal walls with a narrow trough that is more evident at the vertices; seeds 0·32–0·48 mm | O. reticulata subsp. reticulata |
| 5′. | Anticlinal walls with a narrow trough that is visible all around the edge; seeds 0·27–0·36 mm | O. minor |
| 6. | Inner periclinal wall of epidermal seed coat cells with perforations of smaller diameter than the thickness of the walls that separate them | 7 |
| 6′. | Inner periclinal wall of epidermal seed coat cells with perforations of diameter similar to or greater than the thickness of the walls that separate them | 9 |
| 7. | Epidermal seed coat cells in the mid and insertion areas tangentially elongated and isodiametric at the opposite end | O. alba |
| 7′. | Epidermal seed coat cells isodiametric on the entire surface | 8 |
| 8. | Anticlinal wall junctures with a narrow trough that is visible all around the edge of the cells | O. crenata |
| 8′. | Anticlinal wall junctures with a narrow trough that is evident at the vertices of the cells | O. ballotae, O. calendulae,O. reticulata subsp. reticulata |
| 9. | Perforations with a similar diameter to the thickness of the wall that separates them | 10 |
| 9′. | Perforations with a diameter which is larger than the thickness of the separating wall | 16 |
| 10. | Epidermal seed coat cells with anticlinal walls of remarkable depth | 11 |
| 10′. | Epidermal seed coat cells with anticlinal walls of medium depth | 13 |
| 11. | Anticlinal wall junctures with a narrow trough that is evident at the vertices of the cells | O. gracilis |
| 11′. | Anticlinal wall junctures with a narrow trough that is visible all around the edge of the cells | 12 |
| 12. | Tangentially elongated epidermal seed coat cells, whose size decreases at the area of insertion; seeds ovoid to oblong | O. hederae |
| 12′. | Isodiametric epidermal seed coat cells on the entire surface; seeds ovoid to subglobose | O. montserratii |
| 13. | Anticlinal wall junctures with a narrow trough that is visible all around the edge of the cells | 14 |
| 13′. | Anticlinal wall junctures with a narrow trough that is evident at the vertices of the cells | 15 |
| 14. | Epidermal seed coat cells tangentially elongated which and narrow and decrease at the area of insertion | O. foetida, O. hederae |
| 14′. | Epidermal seed coat cells more or less isodiametric or irregular | O. cernua, O. elatior subsp. icterica, O. teucrii |
| 15. | Epidermal seed coat cells tangentially elongated | O. crinita |
| 15′. | Epidermal seed coat cells more or less isodiametric | O. amethystea, O. caryophyllaceae |
| 16. | Epidermal seed coat cells with anticlinal walls of remarkable depth and unevenly thickened | O. clausonis |
| 16′. | Epidermal seed coat cells with anticlinal walls of slight or medium depth and evenly thickened | 17 |
| 17. | Seeds trigonous to tetragonal | O. haenseleris |
| 17′. | Seeds ovoid to oblongoid | O. laserpitii‐sileris |
| 18. | Epidermal seed coat cells with anticlinal walls of remarkable depth | O. santolinae |
| 18′. | Epidermal seed coat cells with anticlinal walls of medium depth | 19 |
| 19. | Epidermal seed coat cells tangentially elongated or irregular; seeds oblongoid | O. cumana |
| 19′. | Epidermal seed coat cells more or less isodiametric at the vertices, tangentially elongated over the rest of the surface; seeds ovoid to ellipsoid | O. densiflora |
| 20. | Inner periclinal wall hidden by the outer one | 21 |
| 20′. | Reticulate inner periclinal wall visible through the outer one | 24 |
| 21. | Epidermal seed coat cells with anticlinal walls of slight depth, and a narrow trough that is visible all around the edge of the cells | O. latisquama |
| 21′. | Epidermal seed coat cells with anticlinal walls of medium depth and a narrow trough that is evident just at the vertices | 22 |
| 22. | Epidermal seed coat cells with anticlinal walls unevenly thickened | O. ramosa |
| 22′. | Epidermal seed coat cells with anticlinal walls evenly thickened | 23 |
| 23. | Seeds <0·40 mm; epidermal seed coat cells isodiametric to irregular | O. nana |
| 23′. | Seeds ≥0·40 mm; epidermal seed coat cells isodiametric | O. arenaria |
| 24. | Epidermal seed coat cells with anticlinal walls of slight depth; seeds light grey‐brown | O. olbiensis |
| 24′. | Epidermal seed coat cells with anticlinal walls of medium or remarkable depth; seeds dark grey‐brown | 25 |
| 25. | Epidermal seed coat cells with anticlinal walls of medium depth | O. tunetana, O. purpurea |
| 25′. | Epidermal seed coat cells with anticlinal walls of remarkable depth | 26 |
| 26. | Anticlinal walls evenly thickened | O. mutelii |
| 26′. | Anticlinal walls unevenly thickened | O. lavandulaceae, O. schultzii |