Red algae are exceptional for the great diversity in reproductive morphology and for their complex life histories. In particular, the family Phyllophoraceae, consisting of ~100 species worldwide, stands out in exhibiting a wide spectrum of unique life history types that makes it unusually interesting for assessing the phylogenetic importance of reproductive traits relative to classification criteria. Type of life history and position of the reproductive structures on the plant body have traditionally formed the basis for separating eleven genera in the Phyllophoraceae; however, phylogenetic analyses inferred from three sets of DNA sequences [chloroplast-encoded rbcL, nuclear large-subunit ribosomal RNA gene (LSU), and internal transcribed spacer regions (ITS) of nuclear ribosomal DNA], instead indicate a lack of correlation between type of life history and phylogenetic relationships among the established taxa. This lack of correlation dramatically challenges all of the traditional taxonomy. The study will answer the question which morphological features and which aspects of life history evolution can be used as meaningful indicators of phylogenetic relationships in the Phyllophoraceae. The results will also be addressed in light of global biogeographic hypotheses for the family. (Supported by NSF DEB-9903900 and LA BoRSF(1999-2000)-RD-A-50)

Key words: algae, biogeography, life history, morphology, phylogeny, Rhodophyta