1	"Lobes of synangium pointed"	2
1	"Lobes of synangium round"	3
2	"Leaves broadest in the basal half, asymmetrical"	"Tmesipteris obliqua"
2	"Leaves uniformly wide in the distal half, tapering to the base; margins parallel"	"Tmesipteris truncata"
3	"Leaves 2 or 3 per centimetre of shoot"	4
3	"Leaves 4–6 per centimetre of shoot"	5
4	"Leaves narrowly to broadly oblong, isobilateral; surfaces dull; synangia restricted to middle and upper parts of shoot, deciduous"	"Tmesipteris elongata"
4	"Leaves ovate to ovate-oblong; upper surface shiny; lower surface dull; synangia restricted to the basal part of the shoot, persistent"	"Tmesipteris lanceolata"
5	"Leaves obovate, straight, obtuse, mucronate"	"Tmesipteris ovata"
5	"Leaves lanceolate, curved, acute"	"Tmesipteris parva"