Revision of Passiflora Subgenus Decaloba ... - Passion Flowers

383
differences in the stipe and pedicel lengths of the two species. He used the
following characters to differentiate them: position of the petiolar nectaries, the
number of laminar nectaries, the shape of the stem, leaf venation, the leaf
margin, and the leaf texture. However, in my analysis of these species, I did not
find any of these vegetative characters to be wholly reliable in distinguishing
between these two species. Both have petiolar nectaries that occur in various
positions below the middle of the petiole, stems that are terete to somewhat
compressed, five distinct leaf veins, thick leaf margins and coriaceous leaves.
Passiflora sexocellata does tend to have fewer nectaries than P. coriacea on
average, but there is a significant amount of overlap in the range of variation.
A clone of P. coriacea (MacDougal 3029) did not produce fruits by autogamy
in over 4 years in cultivation. This greenhouse accession was given to me by
MacDougal, who originally received it as seedlings from J. Zarucchi (Zarucchi et
al. 6102).
Heliconius erato (Lepidoptera: Nymphalidae, Heliconiinae) has been reported
to be an herbivore of P. coriacea in the central Colombian valleys (Cauca and
Magdalena) (Benson et al., 1975).
Fajardo et al. (1998) in a study on the genetic variation analysis of the genus
Passiflora using RAPD markers, used P. coriacea and P. adenopoda DC. as
representatives of taxa from subgenus Decaloba. They found P. coriacea to be
genetically distant from the other taxa in his study, including P. adenopoda, but
due to insufficient data, they were not able to discuss the significance of this
result (Fajardo et al., 1998).