Document Type



Master of Science


Biology, Plant Systematics

Date of Defense


Graduate Advisor

P. F. Stevens, Ph. D.


Jorgensen, Peter M.

MacDougal, John M.


Passiflora subgenus Decaloba section Xerogona is a group of herbaceous vines found in subtropical and tropical regions of America. The 15 species, including two subspecies, recognized here are primarily distributed in Central America, with a few also found in South America. The species of the section are recognized by their very unusual dehiscent capsular fruit, absence of bracts and laminar nectaries and their transversely grooved seeds. The section contains two problematic species complexes; P. capsularis and P. rubra. The morphological variation among and within these two complex species are examined in this study using Principal Component Analysis (PCA) based on correlation matrices of morphological characters. The variation of these two complexes was studied throughout their distributional range. Within the P. capsularis complex only one species has been recognized. However, two species were recognized within the P. rubra complex based mainly on floral characters: P. cisnana and P. rubra. A key, detailed descriptions, distribution maps, and photographs are included in the revision. The distribution and ecology of the 15 species recognized are also discussed.

OCLC Number