The publication presents the results of a comparative study of the morphological characteristics of the vegetative and generative organs of plants Tamarix ramosissima Ledeb. and T. odessana Steven ex Bunge. The taxonomic status of T. odessana described by H. Steven from the vicinity of Odessa (Ukraine) is ambiguously interpreted in different floristic reports: it is considered as a separate species or form, it is given the status of a species as part of T. ramosissima, or is not recognized at all. The processing of numerous herbarium specimens (KW) was carried out in order to clarify the question of the possible existence of T. odessana as an independent species. Especially valuable were materials from herbariums M.S. Turchaninov (KW), which presents the only sample collected in Bessarabia, originally identified by V. Besser as "T. tetrandra M.B.", and then redefined as T. odessana. A photocopy of the type sample T. odessana, (Museum Botanicum Univ. (H) Helsinki) was also carefully studied. For comparison, herbarium specimens of T. ramosissima were investigated, in particular, specimen ("No. 718. In arenosis ad lacum Noor-Saisan. Fr. et Augusts. Kar. et Kir. 1840") (KW) collected in the same territory as and type sample T. ramosissima. For greater reliability, other samples of both species were investigated and their initial descriptions were analyzed. According to morphological characters, mainly of generative organs (corolla, petals, sepals, styloid with stigmas) T. odessana differs well from T. ramosissima. The article presents a comparative table with the morphological characteristics of plants of both species and the photos of their vegetative and generative organs, according to which they differ markedly. However, in order to finally resolve the issue of species independence of T. odessana, it would be advisable in the future to draw on molecular biological data that are currently lacking.

Euphorbia davidii Subils (=Euphorbia dentataMichx) and Euphorbia maculata L. are alien species of North American origin that were first discovered in Ukraine in the late twentieth century and are known from a few locations. In recent years, we have identified several new locations of these plants in southern Ukraine. Euphorbia davidii was found in 2 locations: city of Oleshky, Kherson Region (scrap metal base) and the outskirts of the village Prohresivka of Berezanka district of Mykolaiv Region (sunflower field). For the Mykolaiv Region E. davidii is resulted by us for the first time. All previously known localities of E. davidii in Ukraine are confined to railways and ports, probably, the primary centers of plant invasion. The localities identified by us are quite distant from the primary foci of invasion, which indicates the spread of E. davidii beyond their borders on the territory of Ukraine within the secondary range. A number of new E. davidii sites discovered in recent years on railways in different parts of Ukraine and the appearance of the species outside the primary foci of invasion indicate a tendency to naturalize the plant in Ukraine. Euphorbia maculata was found in 7 localities in Kherson (Kherson and environs, Skadovsk, Oleshky) and Dnipropetrovsk (Kryvyi Rig) Regions. For the Kherson Region E. maculata is given by us for the first time. A significant number of new locations, including outside the primary foci of invasion, the high number of individuals in them, indicates a high successful naturalization. At least in the Kherson Region E. maculata is an epecophyte. In addition, in 2019, E. maculata was found by us in Azerbaijan (Baku), where it is very rare. The further spread of E. davidii and E. maculata in Ukraine can be predicted with a high probability.

Despite intensive floristic and geobotanical research on the Dnipro Left Bank, there is a lack of information on the urban flora of medium and small cities. We conducted inventory of the species diversity of Pyriatyn flora and the patterns of its differentiation. The total list of  vascular plants are included 933 species from 5 divisions on the studied territory. We provide information about occurrence in the territorial zones of the city and its coenoflora for each species. The high level of species diversity of urban flora is associated with the preservation of a part of the floodplain of the Uday River and protected areas, as well as a representative floral complex of synanthropic plants, which is enriched new elements due to trade and transport links. The high level of species diversity was fixed in the territorial zones of protected areas (723 species) and recreational use (704), while the areas of engineering infrastructure, utilities, production, special and historical and cultural purposes have low values of species diversity due to the total transformation of the environment. The distribution of coenofloras by level of species diversity indicates that the highest level of floristic capacity is inherent in meadow and fringe ceonoflora, and significant species diversity is concentrated in the settlements occupied by ruderal vegetation. Forest, shrub and steppe coenofloras have reduced species diversity due to high levels of anthropogenic pressure. Dendrogram of floristic similarity of coenoflora within Pyriatyn city, although quite dendrogram of floristic similarity of regional flora to which it belongs, still has a number of specific features, including close integration of ruderal and quasi-natural ceonofloras with coastal and floodplain-forest as a result of apophyte penetration and alien species in natural ecosystems.

The article provides an analysis of the systematic structure of the ancient settlements flora located in the Lower Dnipro basin (Southern Ukraine). Despite the relatively small size, the settlements are characterized by a high level of floristic richness. In 18 studied ancient settlements we recorded 524 species belonging to 281 genera, 74 families, 3 classes and 2 divisions of vasculat plants. The floristic proportion for the flora of ancient settlements is 1: 3.8: 7,1, the generic coefficient is 1.9. The spectrum of leading families of flora (61,8 % of the total species composition) reflects zonal features of the Holarctic floras. Most of them are characterized by a hight rates of the indigenous faction (74% in avarage), which indicate flora as natural. The presence of such families as Chenopodiaceae, Brassicaceae and Boraginaceae in the leading family spectrum, shows a slight shift to the arid flora of the Mediterranean. Another reason is the processes of plant invasion from neighboring agrolandscapes and the corresponding processes of synatropization. Spectrum of the leading genera of flora represented by polymorphic genuses – Veronica (13 species), Astragalus (9 species), Artemisia, Carex, Euphorbia, Galium (8 species). The complete absence of synanthropophytes within the genera Achillea, Allium, Astragalus, Carex, Dianthus, Euphorbia, Potentilla, Salvia, Verbascum is indicative. The genera Allium, Astragalus and Dianthus are fully represented by indigenophytes.

The thirty eight moss species, two moss forms and five moss variations grow on the territory of Landscape Reserve “Sagy”. Chiefly, these species are typical components of the Nothern Black Sea Coast natural phytocoenosis. Two species – Porellaplatyphylla, Pseudocrossidium hornschuchianum – are “Regionally rare" bryophytes of the Kherson region. Place the growth of bryophytic tied up with psamophytic, marsh, meadow biotopes, with biotopes of alder groves, with birch groves (“sagy”) and pine planting. The bryoflora of the reserve is characterized by a variegated spectrum of families with nemoral-boreal species Amblystegiaceae, Mniaceae, Polytrichaceae, Hypnaceae, a noticeable predominance of the number of Brachytheciaceae species, and a low number of Orthotrichaceae species. We found that these briocomplexes had different structures and species diversity. The bryofloristic complexes of psammophytic biotopes (6 species) are similar to the poorer version of the psammophytic forbs-fescue-feather grass steppe bryoflora of the Southern Ukraine, in composition and structure of the moss layer. The difference between the moss cover of psammophytic biotopes of the «Sagy» reserve consists in fewer species of mosses, the absence of side-spore (pleurocarpous) bryophytes from the Polytrichaceae in the moss layer, as well as the low participation of representatives of the Bryaceae. The structure of meadows and the marshes marsh level in the “Sagy” reserve is similar to the depleted version of moss communities of the Lower Dnieper birch marshes without open water space; a characteristic feature, in addition to small species diversity, is the absence of representatives of the Sphagnopsida and Polytrichopsida classes. The bryophyte complex of pine plantations of the reserve (11 species ) is a depleted variant of coenobrioflor lichen pine forests, which were described for the sandy massifs of the Lower Dnieper. The moss complex of alder carpets (12 species) differs from the typical cenobrioflora of black alder forests characteristic of the Lower Dnieper reaches. It is similar to mossy overgrown trees in anthropogenic dendrocenoses (forest strips and forest parks), in species composition and spatial and structural characteristics. In our opinion, the briocomplex of alder sagas has been changed due to anthropogenic impact, namely because of fires. The list of bryophyte species found in birch «sagas» (23 species) partially coincides with the list of mossy floodplain Betula pendula forests, typical of the eastern part of the steppe zone of Europe. The moss complex of the investigated birch nuts is poorer, there are fewer representatives of the Amblystegiaceae family and epigene mosses, and the involvement of the epixel component is enhanced. These structural features can be seen as an example of the specific zonal flora of the natural dendrocenosis of the Northern Black Sea. Comparison of the bryocomplexes associated with the biotopes of the “Sagy” nature reserve showed that they illustrate the possible directions of the evolution of the bryoflora of the Lower Dnieper Sands in the case of a hypothetical humidization of the climate. Changes include an increase in the role of mesophytic and mesogygrophithous species of the Amblystegiaceae, Bryaceae, Brachytheciaceae families, an increase in the number of epixilous moss species in parallel with the preservation of the role of the epigeoid bryogroup.

 In this contribution, new data concerning lichen-forming and lichenicolous fungi in Ukraine are presented. It includes new records, exclusions, and confirmations to the Ukrainian administrative regions or taxa in the genera of Arthonia, Aspicilia, Aspiciliella, Bacidia, Buellia, Cercidospora, Circinaria, Cladonia, Clypeococcum, Codonmyces, Didymellopsis, Didymocyrtis, Heterocephalacria, Laetisaria, Lambiella, Lecanora, Lepraria, Lichenochora, Lichenoconium, Lichenostigma, Lichenothelia, Marchandiomyces, Montanelia, Phaeospora, Placynthiella, Polycoccum, Protoparmeliopsis, Pyrenochaeta, Pyrenodesmia, Pyrenopsis, Refractohilum, Rinodina, Rosellinula, Scytinium, Sphaerellothecium, Sphinctrina, Staurothele, Stigmidium, Taeniolella, Thallinocarpon, Toninia, Trapelia, Weddellomyces, Xanthoparmelia and Xanthoriicola. Among them 28 species of lichen-forming and lichenicolous fungi are new to Mykolaiv region, 21 species new to Dnipropetrovsk region, 17 species new to Cherkasy region, 7 species new to Kherson region, 5 species new to Zaporizhzhia region, 3 species new to Chernivtsi region, 3 species new to Odessa region, 3 species new to Luhansk region, 2 species new to Donetsk region, 2 species new to Kirovograd region, one species new to Ternopil region and one species new to Rivne region. Caloplaca xerica is a new host species for Lichenochora caloplacae. In Ukraine, Aspicilia cinerea is a dubious species and it needs to be removed from lichen list of Cherkasy, Donetsk, Dnipropetrovsk, Kirovograd, Mykolaiv and Zaporizhzhia regions. Lepraria neglecta was erroneously reported for Donetsk, Mykolaiv and Zaporizhzhia regions and should be removed from the species lists of these regions. Miriquidica complanata is erronoeusly reported for Zaporizhzhia regions and should be excluded from the list of this region.