1	"Plants reproducing by spores, never developing flowers or woody cones; plants rhizomatous, sometimes with erect herbaceous stems, often without vertical above ground stems, occasionally floating"	2
1	"Plants reproducing by seeds, these developed on the upper surface of woody bracts or inside ovaries, these usually surrounded by colorful bracts"	8
2	"Plant stems ridged, vertical, above ground and green, often with whorls of branches; leaves in whorls, not green, fused into a sheath enclosing the stem, much shorter than the internodes; spores in terminal strobili"	"Equisetaceae {Equisetum ramosissimum}"
2	"Plant stems not ridged, usually horizontal, often subterranean, if erect not more than 40 cm tall; plants floating or terrestrial; leaves alternate, usually petiolate (petioles often mistaken for stems) with blades over 50 mm long but, if sessil or floating, blades less than 4 mm long"	3
3	"Plants terrestrial ; leaves sessile, less than 4 mm long; stems above ground, prostrate to erect; sporangia located on the upper (adaxial) of leaf-like sporophylls"	"Selaginellaceae {Selaginella}"
3	"Plants terrestrial and leaves petiolate (petioles often mistaken for stems) with blades at least 50 mm long, often much longer or floating and blades less than 3 mm long; sporangia located in sporangia aggregated on the lower surfaces of the blades or on a spike attached to the petiole or the base of the blades; blades simple"	4
4	"Leaf blades simple, entire; sporangia embedded in rachises emerging from the base of the blades or the top of the petioles; plants terrestrial; sporangia thick-walled"	"Ophioglossaceae {Ophioglssum polyphyllum}"
4	"Leaf blades simple to pinnatifid compound; sporangia located on the lower surfaces of the blades; plants terrestrial or floating; sporangia thin-walled"	5
5	"Plants floating, dichotomously branched, with clusters of numerous roots at the nodes; leaves sessile, less than 2 mm long, 2-lobed, one lobe aerial and green, the other hyaline and serving as a float"	"Salviniaceae {Azolla nilotica}"
5	"Plants terrestrial, sometimes growing in shallow water; leaf blades usually compound, considerably more than 4 mm long"	6
6	"Leaves with a petiole terminating in 4 wedge-shaped leaflets; sporangia developed in stalked, globose to ellipsoid, firm-walled sporocarps growing from the rhizomes"	"Marsileaceae {Marsilea}"
6	"Leaves with petioles terminating in a simple or compound blade but never in wedge-shaped leaflets; sporangia aggregated into sori on the underside or the margins of the blades"	7
7	"Sori linear borne on the costal side of a vein and usually covered by an indusium"	Aspleniaceae
7	"Sori more or less circular, borne in lines along the veins or the margins usually without an indusium, usually protected by the reflexed leaf margins"	Pteridaceae
8	"Plants herbs, shrubs, trees or vines; leaves often usually petiolate with well-developed blades, sometimes sessile and scalelike; seeds produced in ovaries, these usually in the same structure as the anthers , both usually surrounded by colorful bracts (Angiosperms)"	Angiospermae
8	"Plants trees or slender shrubs with green stems; leaves on mature branches sessile, opposite or whorled, scalelike; seeds and microsporangia in separate stuctures, subtended by dark, closely appressed bracts that conceal the seeds at maturity or subtended by 2 pairs of red or yellow fleshy bracts (Gymnosperms)"	9
9	"Plants shrubs to tall trees; older stems covered by bark; seeds produced in spherical to ovoid cones"	"Cupressaceae {Juniperus procera}"
9	"Plants shrubs; stems remaining green, without bark; internodes much longer than the leaves; leaves scale-like, opposite or whorled, soon withering and/or falling off"	"Ephedraceae {Ephedra foliata}"