Molecular Evidence for the Wide Distribution of Two Lineages of Terrestrial Green Algae (Chlorophyta) over Tropics to Temperate Zone

Abstract

Phylogenetic analyses of 18S rDNA sequences from environmental clones and culture strains revealed a widespread distribution of two subaerial green algal lineages, Jenufa and Xylochloris , recently described from rainforests in southeast Asia. A new lineage of Jenufa (Chlorophyceae), most closely related to or even conspecific with J. minuta , was formed by sequences of European origin. Two more lineages of Jenufa were formed by three additional sequences from Ecuador and Panama. The other lineage was a close relative of Xylochloris irregularis (Trebouxiophyceae), probably representing a new species of the genus and distinct from the only so far described species, X. irregularis . It comprised two distinct clades each containing almost identical sequences from Germany and Ecuador. Analyses of the new sequences for both genera allowed to presume a preference of J. minuta to subaerial growth on rock or artificial hard substrates combined with a remarkable adaptation to extended periods of darkness, whereas Xylochloris may preferably occur on tree bark or in the soil.