The article provides a list of the conjugating green algae (Streptophyta, Conjugatophyceae) found in overgrown lakes Boevskoe, Tenyak and Shchelkunskoe. 72 species, forms and variaties belonging to the genera Netrium (2), Mougeotia (1), Spirogyra (3), Closterium (13), Actinotaenium (1), Cosmarium (18), Desmidium (1), Euastrum (4), Hyalotheca (1), Micrasterias (8), Pleurotaenium (1), Raphidiastrum (1), Staurastrum (11), Staurodesmus (3), and Xanthidium (4) were identified. 47 species and 3 variaties are new to Sverdlovsk Region.

The article provides an annotated list, which contains 35 species and subspecific taxa of desmid algae collected in 2015 in swamps near Yugorsk city, West Siberia. Twelve species (Closterium costatum, Cosmarium regnesi, Euastrum ansatum, E. gayanum, E. pulchellum, Staurastrum aculeatum, S. arcuatum var. subavicula, S. tohopekaligense, Staurodesmus dickiei var. circularis, S. glaber, Xanthidium cristatum, X. uncinatum) and one variety (Closterium closterioides var. intermedium) are new for the Khanty-Mansi Autonomous Okrug. Data on morphology and distribution of the species are provided.

Species composition of desmid algae and their habitat preferences in water bodies of Ekaterinburg city were studied during the 2013–2017. Thirty-seven species and subspecific taxa which belong to 12 genera and 2 families were identified, of which 17 species are new for the eastern macroslope of the Middle Urals. Canonical correspondence analysis, which was performed to reveal habitat preferences, demonstrates that the majority of analyzed species prefer quarry lakes, ponds and overgrown lake shores, contrary to fens and rivers.

New disributional data on 14 previously unrecorded or rare species and varieties of algae belonging to Closteriaceae, Desmidiaceae, Gonatozygaceae and Peni­aceae (order Desmidiales) are presented for the Middle Urals. Closterium cornu Ehrenberg ex Ralfs, Closterium macilentum Brébisson, Closterium navicula (Brébisson) Lütkemüller, and Cosmarium crenulatum Nägeli are newly recorded to the Urals. A brief description, including measurements of cells as well as regional and global distribution, is given for each taxon.

The paper contains a proposal to include Cosmarium striolatum (Nageli) W. Archer 1861 in the Red Books of the Sverdlovsk and Chelyabinsk regions of the Russian Federation in the category of a rare species (category 3), or as a species with an uncertain status (category 4). Information about the distribution of C. striolatum in the world, as well as data on the finding of the species in the Middle Urals were given.