Seven new species and two varieties of Klebsormidium were described using an integrative approach on the base of 28 strains from the poorly studied phylogenetic superclade G. These strains originated from the unusual and exotic habitats (semi-deserts, semi-arid shrublands, Mediterranean shrub and deciduous vegetation, temperate Araucaria forests, peat bogs, dumps after coal mining, maritime sand dunes etc.) of four continents (Africa, South and North America, and Europe). Molecular phylogenies based on ITS-1,2, rbcL gene and concatenated dataset of ITS-1,2-rbcL, secondary structure of ITS-2, morphology, ecology and biogeography, micrographs and drawings of the investigated strains were assessed. Additionally, phylogeny and morphology of 18 Klebsormidium strains from other lineages isolated from the same localities (different vegetation types of Chile and maritime sand dunes of Germany) were investigated for the comparison with representatives of clade G. Clade G Klebsormidium is characterized by distant phylogenetic position from the other Klebsormidium lineages and prominent morphology: four-lobed chloroplasts and mostly short swollen cells in young culture, compact small pyrenoids, curved or disintegrated filaments, unusual elongation of cells in old culture, formation of specific cluster- and knot-like colonies on agar surface, especially prominent in strains isolated from desert regions, from which the group probably originated. Comparison of Klebsormidium diversity from different biogeographic regions showed that the representatives of clade G are common algae in regions of the southern hemisphere (South Africa and Chile) and rare representatives in terrestrial ecosystems of the northern hemisphere. Further investigation of mostly unstudied territories of the southern hemisphere could bring many surprises and discoveries, leading to a change of the present concept that Klebsormidium is cosmopolitan in distribution.

• Klíčová slova
• Integrative approach, Klebsormidium, New species, New varieties, Phylogenetic superclade G, Southern hemisphere, Streptophyta, Unusual habitats,
• MeSH
• biodiverzita * MeSH
• chloroplasty MeSH
• fylogeneze * MeSH
• intergenová DNA genetika   MeSH
• konformace nukleové kyseliny MeSH
• lesy MeSH
• půda * MeSH
• Streptophyta klasifikace   MeSH
• zeměpis MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• intergenová DNA MeSH
• půda * MeSH

Two new genera (Streptosarcina and Streptofilum) and three new species (Streptosarcina arenaria, S. costaricana and Streptofilum capillatum) of streptophyte algae were detected in cultures isolated from terrestrial habitats of Europe and Central America and described using an integrative approach. Additionally, a strain isolated from soil in North America was identified as Hormidiella parvula and proposed as an epitype of this species. The molecular phylogeny based on 18S rRNA and rbcL genes, secondary structure of ITS-2, as well as the morphology of vegetative and reproductive stages, cell ultrastructure, ecology and distribution of the investigated strains were assessed. The new genus Streptosarcina forms a sister lineage to the genus Hormidiella (Klebsormidiophyceae). Streptosarcina is characterized by packet-like (sarcinoid) and filamentous thalli with true branching and a cell organization typical for Klebsormidiophyceae. Streptofilum forms a separate lineage within Streptophyta. This genus represents an easily disintegrating filamentous alga which exhibits a cell coverage of unique structure: layers of submicroscopic scales of piliform shape covering the plasmalemma and exfoliate inside the mucilage envelope surrounding cells. The implications of the discovery of the new taxa for understanding evolutionary tendencies in the Streptophyta, a group of great evolutionary interest, are discussed.

• Klíčová slova
• Hormidiella, Streptofilum, Streptophyta, Streptosarcina, integrative approach, ultrastructure.,
• MeSH
• DNA rostlinná chemie   genetika   MeSH
• ekosystém * MeSH
• fylogeneze * MeSH
• konformace nukleové kyseliny MeSH
• mezerníky ribozomální DNA chemie   genetika   MeSH
• mikroskopie MeSH
• půdní mikrobiologie MeSH
• ribozomální DNA chemie   genetika   MeSH
• ribulosa-1,5-bisfosfát-karboxylasa genetika   MeSH
• RNA ribozomální 18S genetika   MeSH
• sekvenční analýza DNA MeSH
• shluková analýza MeSH
• Streptophyta klasifikace   genetika   ultrastruktura   MeSH
• transmisní elektronová mikroskopie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Severní Amerika MeSH
• Střední Amerika MeSH
• Názvy látek
• DNA rostlinná MeSH
• mezerníky ribozomální DNA MeSH
• RbcL protein, plastid MeSH Prohlížeč
• ribozomální DNA MeSH
• ribulosa-1,5-bisfosfát-karboxylasa MeSH
• RNA ribozomální 18S MeSH