1	"Petals without a corona; pollen grains free"	2
1	"Petals united to a lobed corona; pollen grains aggregated into pollinia"	5
2	"Plant an erect or trailing herb or subshrub; flowers blue (rarely white)"	Vinca
2	"Plant a woody shrub or climber; flowers white, pink, red, or yellow"	3
3	"Plant a vigorous woody climber to 10 m long or more; fruit a leathery capsule; mainly in wet forests"	Parsonsia
3	"Plant a woody shrub to 6 m high; fruit a drupe or a woody follicle"	4
4	"Corolla less than 15 mm long; plant a procumbent to medium shrub to 2.5 m high; fruit a drupe; restricted to coastal areas"	"Alyxia {Alyxia buxifolia}"
4	"Corolla 25 mm long or more; plant a large shrub to 6 m high; fruit a woody follicle"	"Nerium {Nerium oleander}"
5	"Plant an erect herb or shrub; corolla-lobes strongly reflexed at anthesis"	6
5	"Plant climbing or twining; corolla-lobes never reflexed"	7
6	"Corolla red; corona yellow, segments each with a horn-like appendage; follicle elongate, without spines"	"Asclepias {Asclepias curassavica}"
6	"Corolla white, at least inside; corona white, segments without horn-like appendages; follicle ovoid or globose, soft, inflated, with numerous soft spines"	Gomphocarpus
7	"Corolla white, green, yellowish or pale pink"	8
7	"Corolla finally dark purple or mauve (rarely yellow-green when immature)"	9
8	"Stems and leaves more or less glaucous; corolla-tube white to pink, 10–15 mm long; pollinia pendulous"	"Araujia {Araujia sericifera}"
8	"Stems and leaves green; corolla-tube yellowish, less than 5 mm long; pollinia erect"	Leichhardtia
9	"Leaves and sepals pubescent; corolla lobes c. 8–9 mm long"	"Oxypetalum {Oxypetalum coeruleum}"
9	"Leaves and sepals more or less glabrous; corolla lobes less than 8 mm long"	10
10	"Leaves narrow-linear; corolla-lobes acute, c. 6 mm long; follicles 8–18 cm long; slender mallee twiner"	"Rhyncharrhena {Rhyncharrhena linearis}"
10	"Leaves ovate or elliptic; corolla-lobes obtuse, 2–3 mm long; follicles 5–7 cm long; slender twiner of eastern forests"	"Tylophora {Tylophora barbata}"