Character Evolution in Pleurocarpous Mosses, Especially in the Lembophyllaceae-Neckeraceae -clade

  • Olsson, Sanna (Participant)
  • Quandt, Dietmar (Participant)
  • Huttunen, Sanna (Participant)

Description

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. Raymond Tangney (National Herbarium of Wales, Cardiff), Dr. Sanna Olsson (University of Helsinki), Dr. Sanna Huttunen (University of Turku), MSc. Volker Buchbender (PhD-student, 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 characters 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 and an obsolete costa, have evolved more than one time in the Neckeraceae alone.

In the sister-groups 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 project is to reconstruct the phylogeny of the Lembophyllaceae and Neckeraceae using mainly molecular data and based on a comprehensive taxon sampling. Several new genera have been described in the Neckeraceae, as well as one new family (Miyabeaceae) consisting partly of genera previously placed in the Neckeraceae. One of the main results, which probably also has wider significance for moss evolution in general, is that a few apparently morphologically homogeneous genera with a wide geographic distribution are polyphyletic. Examples of such genera are Thamnobryum and Homalia. Instead, many of the new genera are morphologically relatively heterogenous but have geographically restricted ranges, a fact that indicates homoplasious evolution under similar selection pressures.
StatusActive
Effective start/end date01/01/2001 → …

Keywords

  • 118 Biological sciences