1	"All spikelets unisexual, staminate and pistillate spikelets in separate inflorescences"	"Zea {Zea mays}"
1	"At least one spikelet in each spikelet pair bisexaul"	2
2	"Rachis internodes and pedicels slender, usually not thickening upwards but, if so, upper lemma of bisexual spikelets awned"	3
2	"Rachis internodes and pedicels stout, thickening upwards;  upper lemma of bisexual spikelets unawned"	15
3	"Pedicellate spikelet similar to the sessile spikelet, both seed-forming"	Saccharum
3	"Pedicellate spikelet differing from the sessile in shape and sex, sometomes absent or represented only by a pedicel"	4
4	"Inflorescences panicles with an elongated central axis; raceme internodes never with a translucent median line"	5
4	"Inflorescences  a single raceme, several subdigitate racemes or, if with an elongated central axis, raceme internodes with a translucent median line"	6
5	"Lower glume of sessile spikelets dorsally compressed"	Sorghum
5	"Lower glume of sessile spikelets laterally compressed"	Chrysopogon
6	"Pedicels and raceme internodes with a translucent median line"	Bothriochloa
6	"Pedicels and raceme internodes without a translucent median line"	7
7	"Lower floret of sessile spikelets staminate and with a palea"	8
7	"Lower floret of sessile spikelets sterile and without a palea"	9
8	"Ligules membranous"	"Ischaemum {Ischaemum afrum}"
8	"Ligules composed of a line of hairs"	Sehima
9	"Upper lemma of sessile spikelets awned from low on the back of the lemma"	"Arthraxon {Arthraxon prionodes}"
9	"Upper lemma of sessile spikelets awned from low on the lemma"	10
10	"Lower glume of sessile spikelets 2-keeled; callus inserted on the hollowed tip of the internode"	11
10	"Lower glume of sessile spikelets rounded, not keeled; callus attached obliquely to the internode, its tip free"	12
11	"Racemes not deflexed at maturity, borne on unequal, terete bases; leaves not aromatic"	Andropogon
11	"Racemes usually deflexed at maturity and borne on subequal, flattened bases; leaves nearly always aromatic"	Cymbopogon
12	"Upper lemmas of sessile spikelets 2-toothed"	Hyparrhenia
12	"Upper lemmas of sessile spikelets not toothed, entire"	13
13	"Racemes with 2 large homogamous spikelets at the base that form an involucre"	"Themeda {Themeda triandra}"
13	"Racemes without large homogamous pairs at the base or, if present, not forming an involucre"	14
14	"Sessile spikelets subterete, calluses sharply  pointed"	"Heteropogon {Heteropogon contortus}"
14	"Sessile spikelets dorsally compressed, calluses obtuse"	Dichanthium
15	"Pedicels fused to the internodes"	"Rottboellia {Rottboellia cochinchinensis}"
15	"Pedicels not fused to the internodes"	16
16	"Calluses of sessile spikelets obtuse to acute, with an oblique articulation scar"	Elionurus
16	"Calluses of sessile spikeletstruncate, with transverse articulation scar often reinforced by a central peg"	17
17	"Racemes silky-villous"	"Lasiurus {Lasiurus scindicus}"
17	"Racemes glabrous"	"Vossia {Vossia cuspidata}"