Revision of Passiflora Subgenus Decaloba ... - Passion Flowers

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protect nectar from rain, desiccation, and non-pollinating organisms is
unnecessary, and, while almost all species in the genus have a functional
operculum, both P. itzensis and P. xiikzodz possess a very reduced one,
represented only as minute teeth. Because the flowers of these species do not
produce nectar, it is possible that the pollen itself is the reward or that pollinators
are attracted by deception. The floral floor in both of these species is shiny and
very similar to glistening nectar. In addition, the flower is very dark reddish
purple with very long outer coronal filaments that could be mimicking rotting
flesh, although the flowers do not have a strong odor. The flowers of P. itzensis
are unusual in having short styles and staminal filaments and anthers which
dehisce distally so that pollen is dusted on the ventral surface of any pollinators
walking on the flower (compare Figs. 8.36 and 8.38). The bright yellow color of
the pollen in this species is in sharp contrast to the very dark-colored flower and
may function to attract pollen collectors. Perhaps there has been a shift from the
attraction of pollinators by deception in P. xiikzodz to one in which the pollen is
displayed to pollen gatherers in P. itzensis. The pollination biology of these
sibling species needs detailed study.
Fruit Dispersal
The fruits of supersection Cieca are unilocular berries with thin pericarps that
are very dark purple, sometimes with a glaucous bloom. They may contain few
to many arillate seeds, with the arils mostly clear to slightly opaque and covering
one half to three quarters of the seed. The fruits persist on the pedicels for some
time after maturity and most are probably bird-dispersed, but other forms of
zoochory may also occur. Van der Werff (van der Werff 1951 & 1420) reported