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1 Stem and leaves (midvein on the undersurface) prickly; flower heads (capitula) ovoid to cylindrical in flower and in fruit, (15-) 30-90 mm long; involucral bracts subtending the flower heads ascending to spreading, stiff, elongate, and attenuate, the longer > 30 mm long
....3 Corona (the expanded epicalyx) 16-24-veined; bracts of the receptable (each associated with a flower) pale green, with a brown tip
....3 Corona (the expanded epicalyx) 8-veined; bracts of the recetacle (each associated with a flower) whitish, with a green tip
......4 Calyx without bristles and only slightly toothed
........5 Calyx teeth 8 or more; receptacle hairy-bristly, lacking a receptacular bract associated with each flower; flowers unequal in size within each head, the outer flowers distinctly larger than those near the center of the head
........5 Calyx teeth 4 or 5; receptacle with a receptacular bract associated with each flower; flowers equal in size within each head