Bryological and Lichenological Section/ABLS
Forrest, Laura L. , Schuette, Scott , Stotler, Raymond E. , Crandall-Stotler, Barbara J. .
Molecular and morphological divergences in the simple thalloid liverwort Jensenia Lindb. (Pallaviciniaceae Mig., Marchantiophyta).
Jensenia is a small genus in the Pallaviciniaceae comprised of eight species of dendroid simple thalloid liverworts, with a trans-Antarctic distribution. In an analysis of five chloroplast genes it is well supported as a monophyletic taxon, sister to Pallavicinia, and distinct from the tropical/south temperate genus Symphyogyna. Four chloroplast coding and non-coding regions, the rbcL gene, the rps4 gene and 3’ spacer region, the trnTUGU - trnLUAA intergenic spacer (including the trnLUAA gene) and the atpB-rbcL spacer region, were sequenced, giving a total aligned length of c. 3500 bp. Samples from four Jensenia species from South America, Malaysia and New Zealand and an outgroup taxon from Pallavicinia provided only six parsimony informative characters. Phylogenetic analysis under the maximum parsimony criterion did not produce any significantly supported groupings, although the South American taxon J. crassifrons does appear to be distinct from the other included Jensenia samples. These results suggest that the divergence between species in Jensenia is relatively recent, rather than Gondwanan, as may have been hypothesized based on the geographical distribution of the taxa. A corollary of this is that the present day distribution of Jensenia is likely the product of dispersal rather than vicariance. There may be a link between observed morphological divergences between Jensenia populations and recent mountain-building across the distribution.
1 - Southern Illinois University, Department of Plant Biology, 1125 Lincoln Drive, Carbondale, Illinois, 62901-6509, USA
trnTUGU - trnLUAA
Presentation Type: Poster
Location: Special Event Center (Cliff Lodge)
Date: Tuesday, August 3rd, 2004
Time: 12:30 PM