| 1 | Stipules subpersistent. |
| 1' | Stipules caducous. |
| 2 | Blade scabrous (or scabridulous) above. |
| 2' | Blade smooth above. |
| 3 | Blade normally entire; sparse brown pluricellular on the branchlet. leaves and inflorescences; pistillate inflorescence with 3-8 flowers. |
| 3' | Blade normally 3-7-lobed to -parted, if entire, then dense brown pluricellular hairs on branchlets, leaves and inflorescences; pistillate inflorescences with 10-50 flowers. |
| 4 | Stipules with ± dense, yellow hairs inside; reticulum at the lower lear surrace slightly prominent to plane and mostly covered with arachnoid hairs; blade mostly entire or 5-fid to -parted; fruiting perianth often scabrous. |
| 4' | Stipules glabrous or with sparse white hairs inside; reticulum at the lower leaf surface prominent and usually not covered by arachnoid hairs; blade mostly 3-lobed to -fid; fruiting perianth subvelutinous. |
| 5 | Blade entire or 3-lobed to -fid. |
| 5' | Blade 5-7(-9)-fid to -parted. |
| 6 | Basal secondary veins unbranched; blade always entire. |
| 6' | Basal secondary veins branched; blade entire or lobed to parted. |
| 7 | Stipules 1-3 cm long; pistillate inflorescence branched. |
| 7' | Stipules normally longer than 3 cm; pistillate inflorescence subumbellate. |
| 8 | Secondary veins 5-9 pairs. |
| 8' | Secondary veins (normally) 9-17 pairs. |
| 9 | Blade with appressed hairs on the veins beneath. |
| 9' | Blade with patent hairs on the veins beneath. |
| 10 | Arachnoid indument on branchlets, stipules, main veins of the blade beneath, inflorescence and/or pistillate flowers. |
| 10' | Arachnoid indument normally only in the areoles and on the smaller veins of the blade beneath. |
| 11 | Blade 3-5-parted, with a deeply cordate base. |
| 11' | Blade entire or 3-parted, with a truncate to subcordate base. |
| 12 | Petiole and blade beneath with short, appressed hairs; lenticels of the branchlets conspicuous. |
| 12' | Petiole and/or blade beneath with rather long, patent hairs; Ienticels of the branchlets usually inconspicuous. |
| 13 | Stipules glabrous inside. |
| 13' | Stipules hairy inside. |
| 14 | Blade entire or 3-lobed to -fid. |
| 14' | Blade 5-7(-9)-fid to -parted. |
| 15 | Pistillate flowers in 2 clusters; pedicels in fruit up to 7 mm long; staminate flower with lobed perianth; filaments much longer than the oerianth. |
| 15' | Pistillate flowers separate; pedicels in fruit up to 16 mm long; staminate Bower with deeply parted perianth; filaments shorter than or as long as the oerianth. |
