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& Endress, 2002). In Brunelliaceae , Cephalotaceae , Cunoniaceae , and
some Elaeocarpaceae the nectaries are annular, intrastaminal, and recepta-
cular around the gynoecium base, protruding as lobes between the stamen
filaments (Vogel, 1998a; Matthews & Endress, 2002; Bradford et al., 2004;
HumaƱa & Valdivia, 2004). For Cephalotaceae, Vogel (1998a) noted epider-
mal nectaries on bracts, tepals, and virtually all other aerial parts. In
Connaraceae , the nectaries are placed at the base of the stamens (Matthews
& Endress, 2002). In Oxalidaceae nectaries are located at the base of the
epipetalous stamen/staminode filaments and nectar can be foraged by polli-
nators through a channel formed by each petal claw (Brown, 1938; Matthews
& Endress, 2002).
Fabales. Most members of this order have intrastaminal and hypanthial nec-
taries. Surianaceae is an exception and has no nectaries (Cronquist, 1981).
Fabaceae is biotically pollinated, utilizing mostly bees, birds, and bats (Ar-
royo, 1981; Schrire, 1989) and offering nectar as a reward. Vascularization
of nectaries may be achieved by phloem, xylem and phloem, or no special
vascular tissue (Fahn, 1979). As a whole, nectaries are mesenchymatic, re-
ceptacular, and intrastaminal; sometimes, the abaxial side of the nectary may
be enlarged (Davis et al., 1988; Westerkamp & Weber, 1999). In the basal
members of paraphyletic subfamily Caesalpinioideae (Herendeen et al., 2003),
nectaries are usually located between the stamens and ovary (Fahn, 1979;
Cronquist, 1981; Tucker, 2002; Herendeen et al., 2003). However, in several
genera with a hypanthium (e.g., Balsamocarpon , Caesalpinia , Cercidium ,
Hoffmannseggia , Parkinsonia , Zuccagnia ), Cocucci et al. (1992) found hy-
panthial nectaries, located on the inner surface, from the base up to the
region where the filaments are inserted in a long hypanthial tube, as Fahn
(1979) reported for Bauhinia . In a survey of the nectaries of subfamily Mi-
mosoideae, Ancibor (1969) reported them as receptacular intrastaminal,
between the bases of the filaments and either the ovary base or the gyno-
phore; they can also be placed at the fused bases of the filaments, which may
also be fused with the corolla. No doubt subfamily Papilionoideae is the
most studied because of its economic importance (e.g., Waddle & Lersten,
1973; Fahn, 1979; Cronquist, 1981; Davis et al., 1988; Vogel, 1997; Galetto
et al., 2000; Horner et al., 2003; Bernardello et al., 2004). In taxa with free
stamens, nectar is easy to reach, whereas in diadelphous taxa, nectar accu-
mulates between the carpel base and the filaments, being sought below the
vexillar petal at the base of the filament column, where there are usually two
openings (Vogel, 1997); some diadelphous species, like Coronilla varia and
its relatives, are nectarless (Vogel, 1997). Monadelphous taxa were consid-
ered to be lacking in nectar because of their completely fused staminal tube,
but current findings indicate that some species (e.g., in Chamaecytisus ,
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