1	"Woody shrubs, either always erect, silky hairy and not scandent, or climbing and scrambling in later developmental stages, glabrous; seedling and intermediate foliage not persisting"	2
1	"Slender twiners, new shoots usually villous; heterophyllous, seedling and intermediate stage leaves with persisting dentate and lobed margins"	10
2	"Petals connivent basally, or in the throat, forming a petal tube. base petal colour blue, maroon-red or red-orange, darkening with age"	3
2	"Petals very briefly connivent or free; developing contrasting spots, blotches and lines due to protandrous colour changes, and/or darkening with sex phase change"	8
3	"Erect shrubs, never scandent; petals purple, blue or almost white"	4
3	"Climbers or scramblers at some developmental stages; petals maroon, red or orange or combinations of these"	6
4	"Erect shrubs with little branching to 20 cm; new shoots pilose; leaves clustering, tiny, less than 10 mm long, obovate; flowers terminal on short shoots, peduncles not nodding; petals deep purple or inky blue"	"Marianthus microphyllus"
4	"Branching shrubs to 0.2 x 1.6 m m; new shoots with both pilose and glandular hairs; leaves alternate, elliptic to oblong; 7–25 mm long, 2.3–10.5 mm wide; flowers in leaf axils, +/-nodding on slender peduncles 3–30 mm long; petals dark purple-blue or pale blue to almost white; fruit capsules are hairy"	5
5	"Leaves variable, rounded at base with petioles to 1.5 mm long, with pilose and glandular hairs on both surfaces, eventually becoming glabrous through abrasion; petals purple-blue initially darkening with age"	"Marianthus mollis"
5	"Leaves elliptic to oblong, attenuate at the base with petioles 1–2.5 mm long, glabrous on both leaf surfaces; petals pale blue to almost white initially"	"Marianthus aquilonaris"
6	"Flowers appearing almost regular: petal tube straight with recurving apices, bicoloured orange-red; filaments conspicuously winged and connivent around pistil at petal break"	"Marianthus ringens"
6	"Flowers irregular with a down-curving petal tube; petals maroon-red, some apices laxly recurving; staminal filaments wider at the base but not winged or connivent, and clustering by height"	7
7	"Leaves broad ovate to orbicular, ±sessile; flowers solitary or few; seeds oval. without ridged margins"	"Marianthus paralius"
7	"Leaves elliptic, petiolate; inflorescences up to six flowers in a loose corymb; seeds distinctly ridged at margins"	"Marianthus erubescens"
8	"Petals white, becoming pinker with age, without maroon or purple striations; pollen blue"	"Marianthus candidus"
8	"Petals white, cream or yellow with darkening maroon or purple venation; pollen yellow"	9
9	"Leaves alternate, petiolate, blue-grey-green, margins entire"	"Marianthus bicolor"
9	"Leaves clustering, stem-clasping, sessile, yellow-green, apically trilobed"	"Marianthus dryandra"
10	"Petals cohering persisting; resulting tube bicoloured green-orange without overt colour changes [VIC, SA only]"	"Marianthus bignoniaceus"
10	"Petals either very briefly connivent or always free; petal base colour monochrome, developing contrasting protandrous spots, blotches and lines [WA only]"	11
11	"Flowers almost regular; stamens regularly placed around the pistil; protandrous, contrasting, darker spots developing on all five petals with age"	"Marianthus granulatus"
11	"Flowers irregular; stamens clustering by height; contrasting spots, if present, developing on three of the five petals only"	12
12	"Seedling leaves irregularly tri-lobed; inflorescences branched umbels with a twining rachis 30–120 mm long; individual pedicels and peduncles less than 12 mm long"	13
12	"Seedling leaves very dentate and irregularly lobed; inflorescences few flowered; peduncles and pedicels to 16 mm"	14
13	"Petals free, elliptic; outer petal surface white with prominent purple venation, inner petal surface blue, all darkening with age; ovary similar length to style"	"Marianthus sylvaticus"
13	"Petals briefly connivent, clawed, pale blue, darkening with age and developing contrasting spots on three of five petals; style nearly twice length of ovary"	"Marianthus coeruleopunctatus"
14	"Inflorescences with less than three flowers in an umbel; petals pale blue, developing darker blotches, not spots, in the throat; pollen yellow; fruit without separate pithy cells for seeds; flowers August to October"	"Marianthus drummondianus"
14	"Inflorescences few-flowered corymbs; petals white tinged mauve, developing contrast spots on three petals only; pollen mauve; fruit with distinct pithy cells for seeds, particularly noticeable at the base and apex; flowers March to April"	"Marianthus tenuis"