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Key to Melanthera

Asteraceae

Melanthera

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1 Fertile plants 5-22 dm tall; main stems (2-) 4-15 mm wide at the base of the plant; petiole (2-) 5-40 mm long; larger leaf blades (2.5-) 4-12 cm wide; inflorescence head 0.8-3.2 cm wide with 30-100 flowers; larger phyllaries (2.5-) 3-4 mm wide; corollas 7-9 mm long; [collectively widespread]
1 Fertile plants 0.2-1 m tall; main stems 2-5 (-7) mm wide at the base of plant; petiole 0-5 mm long; larger leaf blades 0.5-4 cm wide; inflorescence head 0.6-1.8 cm wide with 18-75 flowers; larger phyllaries 1.5-3 mm wide; corollas 4.5-6.5 mm long; [s. FL].
  2 Leaf blades linear to elliptic (lower ones sometimes broadly elliptic or rarely all short and broadly elliptic), unlobed or scarcely lobed, usually 5-13× as long as wide; peduncles (2-) 5-20 cm long; phyllaries 4-5.5 mm long; paleae 4-5 mm long
  2 Leaf blades ovate to 3-lobed, rarely elliptic, 1-4× as long as wide; peduncles 2.5-10 cm long; phyllaries 4.5-7 mm long; paleae 5.5-7 mm long