Revision of Passiflora Subgenus Decaloba ... - Passion Flowers

166
taxa. Passiflora megacoriacea and P. sexocellata were recognized as
specifically distinct as a result of this investigation.
Passiflora xiikzodz and P. itzensis are recognized at the specific-level, as
opposed to the subspecific-level, due to consistent differences in floral
morphology which likely resulted from a shift in pollinators. Based upon floral
morphology, the majority of the species in the supersection are probably
pollinated by insects, likely hymenoptera. However, pollination by hummingbirds
has also been reported for several species of the supersection and appears to
have evolved at least twice, once in P. viridiflora and again in the common
ancestor of P. lancifolia and P. macfadyenii, leading to dramatic shifts in floral
form in these species. The species of supersection, for the most part, are not
sympatric and where two or more species coincide, they are found growing at
different elevations or in different habitats. Several species within the
supersection (e.g., P. lancifolia, P. macfadyenii, P. tridactylites, and P. viridiflora)
fit the peripheral isolate model of speciation and have developed divergent
ecological amplitudes that have allowed them to invade novel habitats and
exploit different spectrums of pollinators.
Most of the species of Passiflora supersection Cieca are utilized by common
and widespread species of the subfamily Heliconiinae. Many of the species in
the supersection have only one or two known herbivores, but, as one would
expect, the species that are widely distributed have a greater diversity of
herbivores. The extent and nature of mutual descent between the species of
supersection Cieca and the Heliconiinae, still remains largely unknown.