Revision of Passiflora Subgenus Decaloba ... - Passion Flowers

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mcvaughiana possesses the widest seeds in the supersection (over 3.6 mm
wide) and P. obtusifolia has seeds that are less than 2.3 mm wide. Additionally,
P. mcvaughiana and P. obtusifolia occupy different habitats, with P. obtusifolia
commonly occurring in lower elevation tropical deciduous or semideciduous
forests in Pacific lowlands and foothills and P. mcvaughiana in high elevation
oak, pine/oak, pine or montane mesophytic forests of México.
Passiflora tacana is a newly discovered species from Volcán Tacaná,
Chiapas, México. Like P. mcvaughiana, it occurs in montane mesophytic forests.
However, P. tacana is easily separated from P. mcvaughiana by its foliose
stipules that are more than 3 mm wide. The fruits of P. tacana also possess ca.
20 seeds, whereas those of P. mcvaughiana produce only 2-10 seeds.
Passiflora mcvaughiana is also quite similar vegetatively to P. sexocellata,
though this species does not occur in southwestern México. The leaves of P.
mcvaughiana are not as coriaceous as those of P. sexocellata and are darker
green. In addition, P. sexocellata always possesses 4-13 laminar nectaries often
with 2-4 of the nectaries occurring proximal to the lateral leaf veins. The petiolar
nectaries of P. sexocellata are commonly positioned on the proximal half of the
petiole, whereas those of P. mcvaughiana are positioned on the distal half of the
petiole. Flowers are often produced in long inflorescences in P. sexocellata, and
P. mcvaughiana commonly lacks inflorescences. The fruits of P. sexocellata are
also much larger than those of P. mcvaughiana and possess between 40 and 50
seeds per fruit.