1	"Fertile stamens 4"	2
1	"Fertile stamens 2 (sometimes accompanied by a pair of staminodes)"	15
2	"Corolla with large, 3-lobed lower lip, upper lip absent. Stamens with thick, curved bony filaments; anthers 1-celled, with stiff white hairs along sutures. [Mangrove species or cultivated escapes]"	Acanthus
2	"Corolla equally 5-lobed or 2-lipped. Stamens not with thick, bony filaments: anthers 2-celled, sutures glabrous"	3
3	"Climbers or twining herbs. Calyx entire or split into 12-20 lobes. Capsule seed-bearing at base, crowned by a long stout beak. Seed excavated on one side, large and semiglobose, 1-2 per valve, collateral"	Thunbergia
3	"Herbs or shrubs, not climbing. Calyx 4-5-lobed. Capsule not crowned by a long stout beak. Seed not excavated one side, usually flattened but if small and globular, many more than 1-2 per valve"	4
4	"Corolla more or less regular"	5
4	"Corolla 2-lipped"	13
5	"Mangrove small tree or shrub"	Avicennia
5	"Herbs or shrubs, not of mangrove habitats"	6
6	"Leaves without cystoliths, glandular hairy. Sepals 5, one longer and broader than other 4. Capsule with c. 60 small globular, glabrous seeds in 4 rows, these without hooks at their base. Upper leaves and bracts alternately arranged"	"Staurogyne {Staurogyne leptocaulis subsp. decumbens}"
6	"Leaves with cystoliths, without glandular hairs. Sepals 5, more or less equal in size, or 4 in 2 unequal pairs. Capsule with 2-20 large, compressed, often hairy, seeds subtended by hooks at their base. Upper leaves and bracts opposite"	7
7	"Sepals 4, in 2 unequal pairs at right angles to each other. Capsule cone-shaped, 1-2-seeded. [Corolla lobes 5, but the lowest lobe not joined for the same length as the other four, thus giving a 2-lipped appearance]. Herbs, often spiny"	Barleria
7	"Sepals 5, more or less equal in size. Capsule with up to 20 seeds, cylindrical or club-shaped but not broadest at base. Herbs, not spiny"	8
8	"Inflorescence a dense terminal spike of verticillately-arranged bracts. Filaments of longer pair of stamens with a line of dense, erect, long hairs throughout length"	Hemigraphis
8	"Inflorescence axillary or terminal, usually cymose, if spicate then the spike not dense. Filaments of longer pair of stamens usually glabrous, rarely (in Brunoniella) with short hairs basally, sometimes for whole length"	9
9	"Seeds glabrous, with angular margins, 1-2 per valve. Capsule club-shaped"	Asystasia
9	"Seeds hairy, with smooth margins, more than 1-2 per valve (although all ovules not always developing in Brunoniella). Capsule club-shaped or cylindrical"	10
10	"Capsule club-shaped. Seed with hairs which rapidly expand on wetting confined to margin"	11
10	"Capsule cylindrical. Seed covered all over with hairs which rapidly expand on wetting"	12
11	"Bracts shorter than calyx. Corolla red; lobes short and erect. Inflorescence an axillary, long-peduncled cyme"	"Stephanophysum {Stephanophysum longifolium}"
11	"Bracts longer than calyx. Corolla blue or white; lobes spreading at right angles to throat. Inflorescence of 1-2(-3) more or less sessile, rarely long-pedicellate, flowers in the axils"	Dipteracanthus
12	"Capsule with 18-26 seeds Stigma glabrous. Inflorescence axillary, long-pedunculate, often dichotomously branched, cyme. Large sprawling herb"	Ruellia
12	"Capsule 1-6-seeded. Stigma pubescent. Inflorescence a sessile axillary cluster of single long-pedicellate flowers arising from the axils, an axillary spike, or a long-pedunculate axillary cyme arising from a basal rosette of leaves. Small herbs, often prostrate"	Brunoniella
13	"Inflorescence of 3-5 dense terminal spikes crowded together. Calyx lobes 5, unequal. [Capsule more or less conical, 2-4-seeded]"	"Lepidagathis {Lepidagathis royenii}"
13	"Inflorescence not a dense terminal spike. Calyx lobes 5, equal"	14
14	"Flowers distinctly 2-lipped; lower corolla lip with long hairs and barred area. Capsule cylindrical, 8-24-seeded. Plants not spiny"	Hygrophila
14	"Flowers not distinctly 2-lipped; lower corolla lip without long hairs and barred area. Capsule cone-shaped, 2-4-seeded Plants spiny"	Barleria
15	"Bracts spine-tipped at apex"	16
15	"Bracts not spine-tipped at apex"	17
16	"Calyx segments 5, equal. Flowers distinctly 2-lipped. Corolla tube twisted through 180°, enclosed within a bifoliate involucre of 2 slightly unequal appressed bracts. Anther cells usually inserted at unequal levels (except in D. australis and D. arnhemica). Capsule discoid, with a thickened rim and small apical beak. Seed glabrous, smooth or glochidiate"	Dicliptera
16	"Calyx segments 4, in unequal pairs. Flowers not distinctly 2-lipped. Corolla tube not twisted through 180°, not enclosed by 2 appressed bracts. Anther cells inserted at equal levels. Capsule conical. Seed covered with long hairs which expand on wetting"	Barleria
17	"Corolla not distinctly 2-lipped, the 5 lobes more or less equal"	18
17	"Corolla distinctly 2-lipped, the 5 lobes very unequal"	20
18	"Stamens with filaments U- or T-shaped at apex, each branch with a single anther cell at the extremity. Flowers regular, 2-5 in axillary, long-pedunculate clusters subtended by free, linear bracts. Shrubs. [Wittenoom area of Western Australia]"	Dicladanthera
18	"Stamens with filaments entire at apex, anther cells not separated laterally. Flowers somewhat irregular, in lax or dense spikes, in axillary clusters or paniculate or racemose, not subtended by a number of free linear bracts. Herbs or shrubs"	19
19	"Prostrate herbs, without cystoliths. Sepals 4, unequal, the largest segment usually toothed at apex. Stamens included; staminodes lacking. Anthers globular, dehiscing by a small flap at the base. Capsule conical, c. 28-seeded, the seeds without hooks at their base"	"Nelsonia {Nelsonia campestris}"
19	"Erect herbs or shrubs, with cystoliths. Sepals 5, equal. Stamens exserted from throat; staminodes 2. Anthers linear, dehiscing longitudinally. Capsule club-shaped, 2-4-seeded, each seed with a prominent hook at its base"	Pseuderanthemum
20	"Stamens with a terminal, transverse anther cell. Corolla with upper lip 4-lobed and lower lip entire or the upper lip 2-lobed and these lobes notched and the lower lip 3-lobed. [Southem Q1c1]"	Xerothamnella
20	"Stamens with all anther cells parallel. Corolla with upper lip notched or 3-lobed"	21
21	"Anthers 1-celled. Corolla tube twisted through 180°, enclosed within a cylindrical involucre of 2 outer fused bracts with 2 smaller inner bracts fused to the outer by their midribs"	Hypoestes
21	"Anthers 2-celled. Corolla tube not twisted through 1800; not enclosed within a cylindrical involucre"	22
22	"Anther cells inserted at equal levels"	23
22	"Anther cells inserted at unequal levels"	24
23	"Corolla with upper lip 3-lobed, lower lip entire. Flowers white with deep red-purple markings. Anthers cohering and pubescent at base; filaments with long hairs on undersurface. Capsule flattened, ellipsoid, seed-bearing throughout. Seeds not flattened, 3-7 per valve. Introduced herb with entire leaves. [Darwin area]"	"Andrographis {Andrographis paniculata}"
23	"Corolla with upper lip notched, lower lip 3-Lobed. Flowers deep red-purple, rarely white with red spots in throat. Anthers not cohering at base; filaments shortly pubescent in basal half. Capsule club-shaped, seed-bearing in upper half only. Seeds flattened, 1-2 per valve. Native shrubs often with toothed leaves. [Queensland east coast]"	Graptophyllum
24	"Lower anther cell without a long white basal appendage"	25
24	"Lower anther cell with a long white basal appendage"	27
25	"Inflorescence a dense terminal spike. Flowers c. 3 cm long. Seed minutely puberulent. Rachis, bracts and bracteoles without glandular hairs except for a sparse occurrence on the apex of the bracts. Introduced herb [Darwin ares]"	Justicia
25	"Inflorescence long pedunculate dichotomous cymes arising in the axils. Flowers 1-2 cm long. Seed not puberulent. Rachis, bracts and bracteoles with glandular hairs"	26
26	"Bracts unequal, linear lanceolate, the larger one exceeding the calyx. Stamens exserted. Seed tuberculate. [Cape York Peninsula, Qld]"	Peristrophe
26	"Bracts equal, triangular, not exceeding the calyx. Stamens included. Seed with more or less concentrically arranged, broken ridges. [Tweed River area, NSW]"	"Isoglossa {Isoglossa eranthemoides}"
27	"Calyx lobes 5. Bracts not noticeably white margined"	28
27	"Calyx lobes 4, with or without remnant of 5th lobe. Bracts usually noticeably white-margined or (Justicia tenella) more or less membranous with pellucid area on margin"	30
28	"Bracts and leaves indistinguishable. Inflorescence a loose terminal or axillary spike. Leaf and bract margins toothed, crenulate or rarely entire. [Dry NT and WA]"	Harnieria
28	"Bracts and leaves distinguishable. Inflorescence not a spike. Leaf and bract margins entire"	29
29	"Bracts conspicuous, 5-9 mm long, obcordate, not glandular hairy. Inflorescence a sessile axillary cluster of up to c.10 flowers. Seed smooth tuberculate all over. [East coast, Qld and NSW]"	Harnieria
29	"Bracts inconspicuous, 0.5-2 mm long, triangular or linear-lanceolate, frequently glandular hairy. Inflorescence of 1-5 flowers at the extremities of axillary, often dichotomously branched, long peduncles. Seed with sharp, concial excrescences all over. [Dry inland Qld and NSW or Rockhampton area]"	Rhaphidospora
30	"Inflorescence a dense spike of overlapping, 4-ranked bracts (cone-like), each spike 1-2 cm long, arising in pairs from the axila on slender 10-17 mm long peduncles. Seed with short white hairs all over, these expanding on wetting. Anther backs not hairy. [Once recorded near Caims in 1891]"	"Justicia {Justicia tenella}"
30	"Inflorescence a terminal spike with 2-ranked bracts, spikes often longer than 2 cm, often interrupted at base. Seed glabrous, tuberculate. Anther backs hairy. [All States of Australia except Victoria and Tasmania]"	Rostellularia