1	"Calyx lobes with a distinctly thickened margin and midrib; flowers pink, usually darker at base"	2
1	"Calyx lobes without a distinctly thickened margin but midrib often distinct; flowers pink, white, yellow, blue or mauve"	22
2	"Epicalyx 0.6 times as long as calyx or shorter"	3
2	"Epicalyx 0.7 times as long as calyx or longer"	5
3	"Epicalyx segments less than 6 mm long"	"Hibiscus fryxellii var. mollis"
3	"Epicalyx segments ?more than 6 mm long"	4
4	"Epicalyx segments connate at base; fruit with pedicel only (widespread on sandstone)"	"Hibiscus zonatus"
4	"Epicalyx segments free; fruit with peduncle and pedicel (Kakadu -- Nitmiluk)"	"Hibiscus byrnesii"
5	"Calyx nectaries present; calyx lobes fleshy, bright red (weed of disturbed places)"	"Hibiscus sabdariffa"
5	"Calyx nectaries absent; calyx lobes neither fleshy, nor bright red"	6
6	"Calyx lobes between the ribs usually glabrous or sub-glabrous"	7
6	"Calyx lobes between the ribs usually with moderately dense to very dense stellate hairs"	8
7	"At anthesis, epicalyx equal to or longer than calyx, prickles common on calyx (affin. H.arnhemensis)"	"Hibiscus sp. Spirit Hills"
7	"At anthesis, epicalyx shorter than calyx, prickles scattered on calyx (widespread on laterite)"	"Hibiscus meraukensis"
8	"Foliar nectary present on at least some leaves"	9
8	"Foliar nectary absent from all leaves"	19
9	"Flowers pedunculate (and pedicellate)"	10
9	"Flowers lacking peduncles (pedicellate only) or flowers sessile"	14
10	"Calyx prickly"	11
10	"Calyx not prickly (rarely a few prickles present)"	13
11	"Leaf blades strongly discolorous, lower leaf indumentum very dense; epicalyx segments 10, equal to calyx or shorter"	"Hibiscus inimicus"
11	"Leaf blades weakly discolorous, lower leaf indumentum scattered to moderately dense"	12
12	"Epicalyx segments 8--9, shorter than calyx; stems and leaves scabrid, sparsely hairy (Kakadu - Nitmiluk)"	"Hibiscus byrnesii"
12	"Epicalyx segments 15--19, more or less equal in length to calyx; stems and leaves densely grey-pubescent (East Alligator area)"	"Hibiscus symonii"
13	"Epicalyx segments 14--16, distinctly longer than calyx (Kakadu)"	"Hibiscus aneuthe"
13	"Epicalyx segments 7-9, shorter than or equal to calyx"	"Hibiscus arnhemensis"
14	"Branchlets with stellate hairs of two size classes (fine and coarse) (possibly not reliable; use branchlets prickly/ non prickly to split groups?)"	15
14	"Branchlets with stellate hairs of one size classes (either fine or coarse) or stellate hairs very sparse"	18
15	"Leaf blades strongly discolorous, coarsely toothed (Koongarra area in Kakadu)"	"Hibiscus riceae"
15	"Leaf blades concolorous or weakly discolorous"	16
16	"Leaf blades with the indumentum denser on the under surfaces; basal leaves only ever shallowly lobed (sandstone, Daly River area)"	"Hibiscus bacalusius"
16	"Leaf blades with the indumentum similar on both surfaces"	17
17	"Branchlets with scattered coarse stellate hairs, prickly hairs sparse; leaves scabrid (Litchfield NP)"	"Hibiscus petherickii"
17	"Branchlets with mid dense coarse stellate hairs, prickly hairs abundant; leaves hispid (Kakadu - VRD)"	"Hibiscus fallax"
18	"Branchlets and calyx prickly; calyx ribs with sparse stellate hairs, the body with minute glandular hairs, otherwise glabrous (Arnhem Land)"	"Hibiscus thegaleus"
18	"Branchlets and calyx not usually prickly; branchlets sparsely hairy; calyx ribs and body with moderately dense stellate hairs; basal leaves deeply lobed (Kakadu, Nitmiluk, Bradshaw)"	"Hibiscus arnhemensis"
19	"Branchlets not prickly; stems and leaves densely grey-pubescent (East Alligator area)"	"Hibiscus symonii"
19	"Branchlets prickly hairy"	20
20	"Flowers pedunculate (and pedicellate); calyx at anthesis 26--31 mm long (Western Arnhem Land)"	"Hibiscus inimicus"
20	"Flowers lacking peduncles (pedicellate only) or flowers sessile"	21
21	"Calyx at anthesis 14--18 mm long; leaf indumentum rel dense (Kakadu - VRD)"	"Hibiscus fallax"
21	"Calyx at anthesis 20--25 mm long (Nitmiluk)"	"Hibiscus menzeliae"
22	"Epicalyx obscure, apparently absent; corolla white except at base"	"Hibiscus lobatus"
22	"Epicalyx well developed, at least 2 mm L; corolla white, yellow or mauve"	23
23	"Epicalyx lobes narrowly spathulate, apex rounded; petals bright yellow (H. panduriformis complex)"	24
23	"Epicalyx lobes subulate or linear, rarely ovate and stipitate, acute (then corolla pink); petals white, pale yellow, pink or mauve"	27
24	"Epicalyx lobes 12--19"	"Hibiscus multilobatus"
24	"Epicalyx lobes 6--9"	25
25	"Stems with scattered septate glandular hairs, short stellate and long prickly hairs also present"	"Hibiscus panduriformis"
25	"Stems lacking glandular hairs, only short stellate and long prickly hairs present"	26
26	"Petals 15--24 mm long; leaf blade 2--4.7 times as long as petals"	"Hibiscus fluvialis"
26	"Petals 38--80 mm long; leaf blade 0.6--1.6 times as long as petals"	"Hibiscus austrinus var. austrinus"
27	"Leaves compound or deeply lobed (sometimes upper leaves unlobed or only upper leaves lobed)"	28
27	"Leaves simple, unlobed or very shallowly lobed"	31
28	"All leaves 5-foliolate"	"Hibiscus pentaphyllus"
28	"All or some leaves deeply 3-lobed or 3-foliolate"	29
29	"Locules with a dorsal wing; corolla pale yellow; epicalyx lobes 6--8;"	"Hibiscus vitifolius"
29	"Locules lacking a dorsal wing; corolla white to pale pink or pale mauve"	30
30	"Epicalyx lobes 6--9; calyx lobes triangular, not becoming inflated or enlarging; plant decumbent or prostrate"	"Hibiscus geranioides"
30	"Epicalyx lobes c. 10; calyx lobes ovate, becoming inflated and enlarged when with fruit; plant erect, annual"	"Hibiscus verdcourtii"
31	"Epicalyx lobes connate in lower half"	32
31	"Epicalyx lobes free, or connate only at base"	34
32	"Leaves entire, glands present on at least some leaves; corolla yellow; coastal tree"	"Hibiscus tiliaceus"
32	"Leaves serrate, glands absent; slender shrub; corolla pink or mauve; inland shrub"	33
33	"Epicalyx lobes 10--12 mm long; calyx 17--20 mm long; leaves ovate"	"Hibiscus sturtii var. platychlamys"
33	"Epicalyx lobes 4--8 mm long; calyx 11--15 mm long; leaves broadly ovate"	"Hibiscus sturtii var. campylochlamys"
34	"Calyx less than 25 mm long"	35
34	"Calyx more than 25 mm long"	36
35	"Branchlets prickly with dense stiff tubercular-based hairs, prickly simple or stellate and minute glandular hairs also present but sparse; epicalyx lobes 10-12, 12-18 mm long; corolla pink"	"Hibiscus setulosus"
35	"Branchlets hispid - scabrid, indumentum of stems and leaves of stellate hairs only; epicalyx lobes (3)6--8, 2--13 mm long; corolla mauve"	"Hibiscus leptocladus"
36	"Epicalyx lobes subulate, to c. 13 mm long; leaves ovate, green, hispid; corolla mauve (Keep River)"	"Hibiscus cravenii"
36	"Epicalyx lobes ovate, stipitate, to c. 35 mm long; leaves broadly ovate to suborbicular, grey, velvety-pubescent; corolla pink (Mt Brockman)"	"Hibiscus brennanii"