2005 Volume 97 Pages 127-159
An eight locus analysis using sequences from the chloroplast rbcL, rps4, psbA, atpB and trnLUAA regions, the mitochondrial nad5 region and nuclear 3' LSU and SSU regions for 64 liverworts, nine mosses and five hornworts resolves five well supported lineages within the Marchantiophyta. Treubia K. I. Goebel and Haplomitrium Nees form a clade that is sister to all other extant liverworts. The Blasiaceae H. Klinggr. is sister to the monophyletic Marchantiopsida Stotler & Crand.-Stotl. The Metzgeriineae R. M. Schust. ex Schljakov and Jungermanniidae Engl. emend. Stotler & Crand.-Stotl. are both monophyletic but their relationship to each other is equivocal. Although a sister group relationship is resolved, this node is not strongly supported. All of the remaining simple thalloids, i.e. the Fossombroniales Schljakov emend. Stotler & Crand.-Stotl., the Pallaviciniineae R. M. Schust. emend. Stotler & Crand.-Stotl. and Phyllothallia E. A. Hodgs., form a well-supported clade. The resolution of relationships within the liverworts is improved by the addition of both taxa and sequence characters.