Phylogenetic relationships in Interfilum and Klebsormidium (Klebsormidiophyceae, Streptophyta)

► The genetic diversity of the Klebsormidiales is higher than previously believed. ► A new lineage of Klebsormidium from arid soils of southern Africa is discovered. ► Paraphyly of Klebsormidium caused by Interfilum is demonstrated. ► The habitat occupied is phylogenetically more significant than previously appreciated. ► Morphological homoplasy is demonstrated in several lineages of Klebsormidium.