Research Groups - Plant Biology
Character Evolution in Pleurocarpous Mosses, Especially in the Lembophyllaceae-Neckeraceae -clade
Johannes Enroth, docent, university lecturer
The members in the research group are Dr. Johannes Enroth (Finnish project leader, University of Helsinki), Prof. Dr. Dietmar Quandt (German project leader,
Rheinische Friedrich-Wilhelms-Universität, Bonn), Dr. Lars Hedenäs (Natural History Museum, Stockholm), Dr. Ray Tangney (National Herbarium of Wales,
Cardiff), Dr. Sanna Huttunen (University of Turku, Finland, MSc. Volker Buchbender (PhD-student, Technische Universität Dresden), MSc. Sanna Olsson (PhD-student, University of Helsinki and Technische Universität Dresden), and MSc. Rolf Blöcher (PhD student, Bonn).
The increasing number of studies utilizing DNA sequence data in phylogenetic studies on
pleurocarpous mosses has opened an opportunity to evaluate the evolution of morphological characers within this group. Many characters that have traditionally been regarded as conservative and hence valuable in delimiting higher level taxonomic groups, such as sporophyte orientation, seta length and peristome structure, have been shown to have evolved several times independently in different lineages. Indeed, we have already shown that several characters, such as a reduced peristome, have evolved more than one time in the Neckeraceae alone.
In the Lembophyllaceae and Neckeraceae the disagreement of the taxonomic value of
sporophyte characters has led to frequent changes in their familial circumscription and
position among other pleurocarpous mosses, and in delimitations of genera. A recent
phylogenetic study of Lembophyllaceae suggests a close relationship between these two
families and a circumscription of Lembophyllaceae that favors the inclusion of a
morphologically rather variable group of species in this family.
The main aim of this study is to reconstruct the phylogeny of the Lembophyllaceae and
Neckeraceae using mainly molecular data and based on a comprehensive taxon sampling. Several new genera are being described in the Neckeraceae. One of the main preliminary results is that a few apparently morphologically homogeneous genera with a wide geographic distribution are polyphyletic. Instead, many of the new genera are morphologically relatively heterogenous but have geographically restricted ranges, which points to homoplasious evolution under similar selection pressures.
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