22. Tepals with an abscission line above their bases, partially persistent in fruit; inflorescence 
multiflorous, usually with more than 15 flowers each; leaves (6.5) 12.5 - 23 (30) cm long 
C. neurophyllum 
2p. Tepals without an abscission line, whole persistent in fruit. 
23. Primary domatia present at several pairs of secondary veins, secondary domatia present at least in 
some leaves; lowest pair of secondary veins not strongly ascending C. effusum 
23. Primary domatia present only at lower most pair of secondary veins, secondary domatia absent; 
lowest pair of secondary veins strongly ascending. 
24. Fruit pedicel turbinate from top to bottom, conspicuously swollen all its length; last branching 
of inflorescence usually congested 
C. grisebachii 
24. Fruit pedicel turbinate distally, proximal section rather cylindrical; last branching of 
inflorescence not congested 
C. costaricanum 
6. Leaf surface of mature leaves sparse to densely pubescent at least below (sometimes inconspicuously so). Twig hairs 
straight to curly, appressed to erect. 
25. Indument on lower leaf surface made only of straight appressed hairs, sometimes inconspicuous. 
26. Domatia absent; twigs fistulose. 
27. Leaves conspicuous and densely pubescent underneath, usually 14.5-22.5 cm wide ......... C. formicarium 
27. Leaves incospicuous and sparsely pubescent underneath, usually 5.5-10 cm wide ................. C. napoense 
26. Domatia present; twigs not fistulose. 
28. Leaf area of domatia concave below, ampullous above. 
29. Stamens of whorl III with two sporangia; leaves pinninerved C. heterantherum 
29. Stamens of whorl III with four sporangia; leaves triplinerved or subtriplinerved. 
30. Tepals with an abscission line below their bases, not persistent in fruit; fruit pedicel not 
distinct, turbinate from top to bottom C. alainii 
30. Tepals persistent (at least partially) in fruit; fruit pedicel partially distinct, turbinate distally. 
31. Inflorescence pauciflorous, 1 (3) dichasia each; tepals entirely persistent, complete 
C. ampullaceum 
31. Inflorescence multiflorous, usually more than 15 flowers each; tepals partially persistent 
C. amoenum 
36 
