1	"Leaves always opposite; scales and sometimes hairs forming distinct whorls around each node; stems often readily disarticulating at nodes when dry; flowers usually with 4 petals, rarely 5"	2
1	"Leaves alternate to subopposite; hairs and sometimes scales restricted to axils, sometimes very small and inconspicuous; stems not disarticulating at nodes; flowers always with 5 petals"	7
2	"Leaves linear, up to 1.2 mm long when dry; some shoots developing globose internodes with which disarticulate readily and act as propagules"	"Portulaca glover & Gilliland"
2	"Leaves lanceolate to ovate; all internodes similar, never globose"	3
3	"Stems prostrate, rooting at the nodes; plants forming dense mats; nodes with woolly hairs ony; cells of seed coat with clearly defined straight margins, uniformly domed"	"Portulaca quadrifida"
3	"Stems erect or ascending, only occasionally rooting adventitiously at nodes; plants forming dense tufts; nodes with scales, with or without hairs; cells of seed coat with obscure or sinuate margins, flat or with distinct central papillae"	4
4	"Nodes with abundant, more or less ciliate hairs, lower nodes also with narrow, darker scales; stigmas 2-lobed, lobes long; capsule lides with subterminal constriction which retains 1 or 2 seeds above it"	"Portulaca constricta"
4	"Nodes with woolly hairs or with scales, scales sometimes split into morestly hair-like segments; stigmas 3-4-lobed, lobes short; capsule lids not constricted"	5
5	"Nodal scales lanceolate, overlappping laterally, often concealing leavves; seeds bown with slight iridescence"	"Portulaca wightiana"
5	"Nodal scales very narrow, superficially hair-like, usually not concealing leaves; seeds grey or glossy brown"	6
6	"Seeds grey; cells of seed coat flat or with a small central tubrcle"	"Portulaca commutata"
6	"Seeds light brwn, glossy; cells of seed coat raised but not tuberculate"	"Portulaca Merla et al"
7	"Stem bases thickened, more or less tuberous; petals purple; seeds brown, cells of seed coat with prominent, cylindrical/peglike tubercles"	"Portulaca nogalensis"
7	"Stem bases only slightly thickened; petals yellow, orange, or red; seeds usually grey to black, often iridescent; seed coats variously ornamentes but if their cells tuberculate, the tubercles only more or less conical or seeds black or if seeds brown then cells of seed coat only slightly raised, not tuberculate"	8
8	"Leaf axils with  scales or hairs up to 1 mm long, often appearing glabrous; seeds black, cells of seed coat priminently stellate, usually with prominent slender tubercles and no metallic lustre or iridescence"	"Portulaca oleracea"
8	"Leaf axils with at least some long hairs and/or scales; seeds grey or brown, often with metallic lustre or iridescence"	9
9	"Petals red or orange; seeds iridescent, cells of seed coat with well-defined conical tubercles"	10
9	"Petals yellow; seeds usually glossy, never iridescent, almost smooth"	11
10	"Plants annual; stems less than 3 mm thick at the base; stamens 10-15(-25)"	"Portulaca kermesina"
10	"Plants perennial; stems over 3 mm thick at the base; stamens about 30"	"Portulaca decorticans"
11	"Leaf axils with a mixture of hairs and much longer, very slender scales, usually brownish"	"Portulaca somalica"
11	"Leaf axils with only white wooly hairs in compact tufts"	12
12	"Plants perennial; stamens 30-50; cells of seed coat with more or less straight margins"	"Portulaca ciferrii"
12	"Plants possibly annual; stamens fewer than 25; cells of seed coat with strongl undulate margins"	"Portulaca Thulin 6398"