1	"Leaf upper surface glabrous, domatia present as tufts of hairs on lower surface"	"Uncaria callophylla"
1	"Leaf upper surface variously hairy, domatia present or absent"	2
2	"Midrib, lateral and minor venation depressed above on dried material; domatia absent"	"Uncaria cordata"
2	"Midrib and lateral venation raised above, minor venation flat above; domatia present"	"Uncaria lanosa {Uncaria lanosa var. appendiculata}"