Angustifolia: Answers to key questions in Budd's Flora leading to this species. 

staminate part of spike separated from pistillate part by 3-5 cm; NOT [staminate part of spike contiguous with pistillate part]

Typhaceae: Answers to key questions in Budd's Flora  leading to this family. 

	plants not aquatic, or if growing in water, most of the plant emersed; NOT [plants aquatic, floating or submerged, with floating leaves or emersed inflorescence]
	inflorescence a dense, single, cylindrical spike 8-15 cm long, 1-2.5 cm thick; NOT [inflorescence not as above; if a single spike, less than 1 cm thick]
	spike bractless; NOT [spike subtended by a large bract or spathe]
	spike not fleshy
	perianth absent or inconspicuous; NOT [perianth present, conspicuous, in two series of 3 segments, often brightly colored]