| 1 | Leaf blade 3-foliolate (or partly simple) |
| 1' | Leaf blade simple (unlobed or lobed) |
| 2 | Plant (sub)annual; monoecious. Probract absent. Male bracts 1(-2) mm long, often caducous. Corolla 20(-30) mm diameter. [Fruit small, ovoid, or long- cylindrical in cultivated var. anguina.] Seeds compressed with undulate edge |
| 2' | Plant (sub)perennial; monoecious or dioecious. Probract present (absent in T. pilosa). Corolla 30 mm diameter or more. Seeds tumid or compressed, not with undulate edge |
| 3 | Leaf blade ± 5-angular, [blackish on drying, with minute glands close to the insertion of the petiole]. Male bracts entire. [Sepals usually with distinct, narrow, lateral lobes.] Fruit (depressed) globose. Seeds compressed, (narrowly) elliptic, chisel-shaped pointed at base |
| 3' | Leaf blade various. Male bracts entire or mostly incised. Fruit (short-)ovoid, obovoid, or ellipsoid. Seeds tumid or compressed, not pointed at base |
| 4 | Plant with fruit (and female flowers) |
| 4' | Plant with male flowers |
| 5 | Fruit ± ellipsoid, 10-18 cm long; fruiting pedicel 10-20 mm thick. [Seeds compressed, obovate or elliptic, (8-)9-11(-25) mm long.] |
| 5' | Fruit ovoid or ellipsoid; fruiting pedicel 2-4 mm thick |
| 6 | Seeds tumid (barrel-shaped or (sub)fusiform) (Fig. 91b). Fruit mostly striped |
| 6' | Seeds compressed. Fruit evenly coloured |
| 7 | Leaf blade subhastate (or 3-foliolate). Fruiting pedicel 2-7 cm long. Seeds 9-13 by 4-7 by 2-3 mm |
| 7' | Leaf blade suborbicular, 3-lobed to halfway deep. Fruiting pedicel 0.5-2.5 cm long. Seeds 10-13 by 5-10 by 1-3 mm |
| 8 | Leaf blade deeply 5-lobed. Peduncle 9-18.5 cm long; rachis 5-10 mm thick |
| 8' | Leaf blade (sub)unlobed or 3-lobed. Rachis (1-)2-3 mm thick, peduncle usually shorter |
| 9 | Plant (dark) brown on drying. Bracts obovate or rhomboid, 15-25 mm long. Leaf blade ± glabrous, 3-lobed to c. halfway the blade |
| 9' | Plant greenish on drying. Bracts (narrowly) elliptic, 25 mm long or less. [Leaf blade various.] |
| 10 | Leaf blade usually ± hairy beneath. Persistent part of pedicel 2 mm long or more |
| 10' | Leaf blade glabrous. Persistent part of pedicel less than 2 mm long |
