MUELLER, KAI1*, THOMAS BORSCH1, LAURENT LEGENDRE2, EBERHARD FISCHER3, STEFAN POREMBSKI4, and WILHELM BARTHLOTT1. 1Botanisches Institut und Botanischer Garten, Friedrich-Wilhelms-Universitaet Bonn, Meckenheimer Allee 170, 53115 Bonn, Germany; 2Centre for Horticulture and Plant Sciences, Department of Science and Technology, University of Western Sydney, Locked bag 1, Richmond, NSW 2753, Australia; 3Institut fuer Biologie, Universitaet Koblenz-Landau, Rheinau 1, 56075 Koblenz, Germany; 4Institut fuer Biodiversitaetsforschung, Allgemeine und Spezielle Botanik, Universitaet Rostock, Wismarsche Strasse 8, 18051 Rostock, Germany. - The evolution of carnivory in the Lamiales: evidence from matK and adjacent noncoding regions.
The Lamiales comprise about 20 families with approximately 18000
species. The relationships of the carnivorous families
(Lentibulariaceae, Byblidaceae) remained uncertain in previous
phylogenetic analyses and so did the evolution of characters being
part of the carnivorous syndrome. Also, the question of how many times
carnivory evolved in the Lamiales remained unanswered. To address
these issues, we sequenced the matK gene and the noncoding
parts of the trnK intron (about 2700 bp) of nearly 100 species
representing all major groups of the Lamiales with an emphasis on both
the taxa with accepted carnivory and taxa with presumed preadaptations
(e.g., Martyniaceae). In the trees obtained from parsimony analyses,
the deeper nodes that show the branching order of the major groups
receive low statistical support due to short branches. This is a
phenomenon also found in all previous studies using other molecular
datasets. However, Oleaceae are resolved as sister to all other
Lamiales with high statistical support and in addition are
characterized by several long insertions. The monophyly of most of the
included families is well supported statistically, with the exception
of the non-monophyletic former Scrophulariaceae and Pedaliaceae. The
data indicate that carnivory evolved independently in Lentibulariaceae
and the other carnivorous taxa. Within the Lentibulariaceae the
majority of nodes gain very high statistical support.
Pinguicula is sister to a clade comprising Utricularia
and Genlisea. The sequence variability of the matK
coding region proved to be equally high as that of the adjacent intron
parts. The transition/transversion ratios in both coding and noncoding
sequences are close to 1.0. The variability of the 3rd
codon position is only slightly higher than of 1st and
2nd positions. Within Lentibulariaceae Utricularia
and Genlisea display a five times greater sequence variability
than Pinguicula.
Key words: carnivory, Lamiales, Lentibulariaceae, matK