Revision of Passiflora Subgenus Decaloba ... - Passion Flowers

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plants, suggesting that a criterion of monophyly for species recognition may be
inappropriate. It is quite possible that P. suberosa has been caught in the
paraphyletic "stage" of speciation, and the data indicate that it might be more
logical to view the phylogenetic status of a species as a property that may
change over time. Peripherial isolate speciation, such as that which presumably
has given rise to the Galapagos endemic, P. tridactylites. Passiflora tridactylites
possesses a flower that appears to be adapted to a larger pollinator than its
relative P. suberosa, which is mainly pollinated by hymenopterans, and P.
tridactylites may be moth pollinated. The analyses also indicate that there is
limited gene flow, likely in the form of hybridization, occurring between P.
suberosa and P. pallida. This gene flow has obscured the distinctiveness of P.
pallida, a species that is likely sister to the remaining members of the
supersection, and has contributed to the traditional broad circumscription of P.
suberosa. Passiflora pallida and P. suberosa have also been shown to be
polyploids (including triploid, tetraploid and hexaploid counts). The exact impact
that hybridization and polyploidy are having on the evolution of P. pallida and P.
suberosa is unknown; however, it is clear that these processes have blurred the
distinctiveness of these two species and made the sorting out of phylogenetic
relationships between and within them very difficult.
Three species from the P. coriacea complex are recognized: P. coriacea, P.
megacoriacea, and P. sexocellata. It is clear in the molecular analysis that P.
coriacea and P. sexocellata are sister to each other, and both are clearly
diagnosable. It is also likely that P. megacoriacea is closely related to these two