Abstract Detail

Systematics Section/ASPT

Svoboda, Harlan [1], Ballard, Harvey [1].

Phenetic and micromorphological studies in Passiflora sect. Dysosmia (Passifloraceae).

One of the most unique and recognizable groups in the passionflower genus, section Dysosmia (Passiflora, Passifloraceae), has long been a source of confusion for taxonomists since its circumscription nearly 200 years ago. A suite of traits, including glandular trichomes and highly divided stipules and involucral bracts, is found nowhere else in the genus. Although unique from the rest of Passiflora, there is a great deal of gross morphological similarity (particularly in the leaves) within the section. These similarities have led to the hypothesis that there may be a number of clades or species complexes in Dysosmia. The morphology and position of glandular trichomes, as well as the degree of dissection in the stipules and involucral bracts, was intensively studied and documented in the hopes that these characters would provide more (perhaps better) traits for species distinctions and comparisons. These micromorphological characters, along with leaf measurements, were quantified for 63 taxa and subjected first to a principal coordinates analysis (PCoA) then to a canonical variates analysis (CVA) to elucidate morphological affinities within sect. Dysosmia. The results indicate that there are three distinct morphological groups, separating out largely on the basis of vegetative pubescence and fruit color, that may represent evolutionarily distinct clades in the section, here distinguished as the P. foetida, P. ciliata, and P. urbaniana clades. Interpreting the relationship between morphology and evolutionary history will lead to a more complete understanding of the diversity and taxon composition in sect. Dysosmia and its place within Passiflora.

1 - Ohio University, Department of Environmental and Plant Biology, 315 Porter Hall, Athens, OH, 45701, USA

Keywords:
Passiflora
Dysosmia
micromorphology
Passifloraceae
phenetics.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PSY025
Abstract ID:751
Candidate for Awards:None