XVI International Botanical Congess

The Blechnaceae is a monophyletic group of higher ferns that appears to have originated in the middle Cretaceous. The family of 280 species has a south temperate to tropical distribution. Phylogenetic analysis using both morphological and chloroplast nucleotide sequence data (RPS4 & rbcL) support the monophyly of Stenochlaena and Woodwardia, with Woodwardia sister to the core Blechnaceae and Stenochlaena sister to the combined Woodwardia-core Blechnaceae clade. Relationships within the core Blechnaceae are complex. Characters traditionally considered of taxonomic importance, such as frond dimorphy and vein reticulation, are homoplastic. Although the monophyly of certain traditionally recognized genera (e.g., Doodia and Sadleria) is supported, recognition of these groups renders Blechnum paraphyletic.