Page 2: Revision of Pandanus, 1. Key to Sections — S t. John 
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KEY TO THE SECTIONS 
A. Drupes all or mostly 1 -celled (subgenus Loph o stigma ) , 
B. Stigmas broader than long, flat, 
C. Stigmas flush, horseshoe-shaped, glabrous; drupes ellipsoid; syncarps solitary, spicate, or 
racemose: stamens umbellate at apex of column Micro stigma 
C. Stigmas raised; drupes cuneiform or fusiform, 
D. Stigmas as broad as or broader than apex of drupe, 
E. Stigmas oblate capitate, emarginate, as broad as the narrow apex of the fusiform 
drupe, in anthesis hirsute; heads single; staminate flowers unknown ....Pulvinistigma 
E. Stigmas discoid suborbicular, entire or lobed, broader than the cuneiform drupes, 
glabrous, imbricate and concealing the drupes; staminate flowers unknown 
Asterostigma 
D. Stigmas narrower than apex of drupe, lunate, lateral under a horizontal, coriaceous, 
entire or lobed visor borne asymmetrically on the apical region of the drupe but not 
marginal; staminate flowers unknown Maysops 
B. Stigmas longer than broad or orbicular, 
F. Stigma 1 (rarely 2), setiform, at maturity deciduous from the pileus; staminate flowers 
unknown Rykiella 
F. Stigmas broader than setiform, persistent, 
G. Stigmas erect, crested and laterally expanded; staminate flowers unknown Cristata 
G. Stigmas not crested, 
H. Style subulate, apical, erect or ascending, bearing a distal stigma; stamens attached 
to axis, the column lacking . Acrostigma 
H. Stigmas broader than subulate, 
I. Stigma on lateral edge of pileus, and horizontal, toothlike, entire; stamens 
crowded on conical apex of column Lophostigma 
I. Stigma terminal, 
J. Stigma a flat flap, entire or lobed, often orbicular or reniform, ascending or 
spreading; stamens umbellate on adaxial side of column apex Microstigma 
J. Styles 1 (-2), toothlike to broad subulate, hornlike, cartilaginous, erect 
or spreading, bearing a proximal stigma; stamens fascicled at apex of 
column Rykia 
A. Drupes or phalanges all or mostly several -celled (subgenus Pandanus ) , 
K. Marginal carpels the smaller, acerose toothlike, mostly sterile; phalanges 5-10-celled; sta- 
mens few, on dichotomous apex of column . . Stephano stigma 
K. Marginal carpels not toothlike and sterile, 
L. Stigmas elongate, acerose, 
M. Stigmas acerose, mostly forked; stamens umbellate on capitate apex of column 
Multispina 
M. Stigmas of simple, acerose spines; staminal column bifid with digitate filaments that 
are simple or 2- 3-forked.. Acanthostyla 
L. Stigmas not acerose elongate, 
N. Stigmas apical and oblique or erect ( or a small percentage of them horizontal ) , 
O. Carpels in 1 transverse line or in several parallel such lines; stamens borne under 
a peltate apex of the column, or in several racemes with subtending bracts... 
Hombronia 
O. Carpels in circular, centripetal, or irregular arrangement, not a linear one, 
