Алексей Павлович Лактионов

The article presents the results of an integrative floristic study conducted in 2025 in the western Caspian region (Kazakhstan and Turkmenistan) and the Sistan region (SE Iran). The study aimed to systematize and analyze new data on the distribution of rare, relict, and alien vascular plants in the Inder salt-dome area of Kazakhstan, in key regions of western Turkmenistan (Southern Pre-Ustyurt, the Bolshoy Balkhan Range, and Ogurchinsky Island) and southeastern Iran (Sistan Basin, the bottom of the former Hamun lake and its surroundings). Based on field expeditions (during which 236 herbarium specimens were collected) and critical analysis of regional floras, several new taxa were identified: Sabulina tenuifolia for Kazakhstan; Amberboa nana, Senecio glaucus subsp. coronopifolius and Polygonum neglectum for Turkmenistan. Juncus minutulus, previously known in Kazakhstan only from the Tian Shan, is reported for the first time from western Kazakhstan (Atyrau Province). In Turkmenistan, new regional records were obtained for the Southern Pre-Ustyurt, and 12 new species were documented for the flora of Ogurchinsky Island, reflecting rapid anthropogenic transformation of ecosystems due to forage importation for gazelles. Additionally, 5 new plant records are reported for the poorly studied Sistan region. These findings highlight the conservation importance of karst landscapes as biodiversity refugia and the need for enhanced monitoring of invasive species in Caspian ecosystems.

This article presents new floristic records for vascular plant species in the Eastern Caucasus, Kazakhstan, Central Asia, and Armenia, based on field surveys conducted between 2018 and 2024 and a critical revision of herbarium specimens deposited in the collections of LE, ERE, TAD, PPIU, DAG, and MHA. In total, approximately 40 new localities are documented for 24 species, encompassing endemic, Red Data Book, and alien taxa. In Tajikistan (Eastern Gissar and Central Zeravshan subregions), five new populations of endemic species were recorded: Nepeta subhastata, N. odorifera, N. gontscharovii, Eminium alberti. In Kazakhstan (Inder Solyanokupolnyy Province [belongs to the Caspian Lowland; located within the Inder District in the north of the Atyrau Region of Kazakhstan], West Kazakhstan Region), seven species are reported as new to the regional floras, including Astragalus sareptanus, A. astrachanicus, Matthiola superba, Zygophyllum ovigerum, Rorippa wolgensis, and Jurinea persimilis; most of these findings are associated with karst landscapes that served as refugia during the Khvalynian transgression of the Caspian Sea. In the Russian Federation, Tanacetum macrophyllum and Digitalis ferruginea subsp. schischkinii are reported for the first time for Dagestan, Poacynum sareptanum – for Kalmykia (based on herbarium re-identification), and the North American invasive Grindelia squarrosa – for the Astrakhan Region, where it is actively spreading along roadsides. In Armenia, twelve new locality records are provided for eight species across several floristic regions, including the endemic Ferula dseghica (Yerevan floristic region), the relict Monotropa hypopitys (Sevan floristic region), new records of Parnassia palustris for the Zangezur floristic region, and the adventive Digitaria ciliaris for the Yerevan floristic region. The results highlight the conservation significance of karst landscapes in Kazakhstan and subalpine habitats in Tajikistan as refugia for rare endemics and underscore the active expansion of alien species along transportation corridors in the Caspian lowlands. The data contributes to updateing regional floristic checklists and Red Data Books.

A new hybridogenic species of the genus Astragalus of the section Paracystium Gontsch. – A. ivanovii – has been described from Western Kazakhstan. It is very likely derived from hybridization of A. lasiophyllus Ledeb. × A. sytinii Belous et Laktionov. On the other hand, in moderately saline soils, only A. ivanovii grows, where it apparently reproduces without the participation of probable parents. Thus, it is not a nothospecies but a partially stabilized taxon. The article includes author’s photographs of A. ivanovii and the species compared to it, as well as a photograph of the community where the type and isotypes have been collected. The article also provides an original key for identifying A. ivanovii and its probable parents, A. lasiophyllus s. str. and A. sytinii.

It is noted that one of the collections used by Alexander von Bunge in describing the Astragalus biebersteinii Bunge (section Paracystyum Gontsch.) (Bunge, 1868, 1869) “... supra Altyagatsch. 21 VII 1855 [Seidlitz]”, differs sharply from the lectotype of this species “...circa Kurt Bulak, 1796”, but quite similar to A. massalskyi Grossh. (section Cystium Bunge), differing from the latter in leaflet shape and pods pubescens. Identical specimens have been identified in herbarium collections of LE and DAG. A new species A. cordigerus Knjaz., Laktionov et Murtaz., sp. nov. is described. An original key for the identification of A. cordigerus and some similar species of sections Cystium and Paracystium is given.

Using the hydrodistillation method, samples of essential oil were obtained from the ground parts of Melilotus officinalis and Melilotus albus, growing wild in the Astrakhan region during the flowering phase. The duration of the steam distillation process was established experimentally based on studying the dynamics of changes in the yield of essential oil over time. The yield of essential oil was determined in % based on the weight of absolutely dry raw materials. The highest yield of essential oil is obtained from plants during the flowering phase (0.8–0.9%). Using gas-liquid chromatography, a quantitative analysis of the main components of the essential oil samples of M. officinalis and M. albus was carried out. The quantitative content of essential oil components was calculated from the areas of gas chromatographic peaks without using correction factors. Qualitative analysis was performed by comparing linear retention indices. The main component of the essential oil of M. officinalis and M. albus is coumarin, the content of which is 86.37 and 80.02%, respectively. In the essential oil of M. albus, the major components are also di-2-ethylhexyl ester of palmitic acid (10.5%), carvone hydrate (1.49%), and humulene (1.10%). Other major components of M. officinalis essential oil besides coumarin are phenylethyl alcohol (3.19%), caryophyllene (2.15%), actinidin (1.39%), and dihydrocoumarin (1.29%).

This article provides information about the discovery of new and rare plant species in the Caspian region and Southwest Asia. In total, the article presents new findings for 19 species of vascular plants from 5 countries, registered during field research, as well as during the revision of herbarium materials. For the first time, Lycium ruthenicum is reported for the flora of Armenia. A new record for the flora of Russia is Valeriana plagiostephana collected from the territory of Dagestan, and Gelasia tuberosa is for the first time reported for the flora of Turkmenistan. The remaining 16 findings, while not new to the countries, significantly expand the understanding of the distribution of these species. Thus, for the flora of Armenia, new locations of some rare and alien species are given that complement existing information (Foeniculum vulgare, Tripidium ravennae, Eleusine indica, Bothriochloa bladhii, Cleistogenes serotina, Adiantum capillus-veneris, Dianthus transcaucasicus). In Iran, three species (Chaerophyllum aureum, Heliotropium circinatum, and Bryonia monoica) are reported for the first time for Kurdistan (Western Iran) and one species (Haplophyllum canaliculatum) for Sistan and Baluchistan (Southeastern Iran). For the first time, Crassula vaillantii and Marsilea strigosa are indicated for the Atyrau Region of Kazakhstan. Bupleurum tenuissimum is given for the first time for the flora of Dagestan (Russian Federation). In Turkmenistan, a new location of the rare species Jurinea transhyrcanica was discovered for the first time in the western part of the Central Karakum, and a population of Crataegus germanica, which was considered extinct, was discovered in the South-Western Kopet Dag. For each species information on location, general distribution, occupied habitats and population status is provided.

The necessity of the typification of the Apocynum L. s.l. (incl. Poacynum Baill. and Trachomitum Woodson) (Apocynaceae) species is crucial for future dogbane diversity estimations. Still, the original material of many taxa of the genus Apocynum s.l. is doubtful or remains to be discovered. This study’s topic is resolving a long-term taxonomic homonymy around the widely used binomial “A. sibiricum”. The misusing of the name “A. sibiricum” became a reason for long-term misunderstanding of the meaning of the binomial Poacynum sarmatiense (Woodson) Mavrodiev, Laktionov & Yu.E.Alexeev (A. sarmatiense (Woodson) Wissjul.; T. sarmatiense Woodson) and therefore for the misestimation of the Apocynum s.l. diversity in Russian and other Eurasian floras. Resolving this issue, here, we designate the lectotype of A. sibiricum Jacq. and the name “A. sibiricum Pall.” was validated within Poacynum as P. pallasianum Mavrodiev, Sytin, Laktionov & Vasjukov nom. nov. (Apocynum sibiricum auct., non Jacq.) with the lectotype selected from the original collections of Peter Simon Pallas.

Studying the floristic composition and dynamics of vegetation in pasture landscapes is of great importance. Pasture landscapes serve as a resource for livestock development, where processes of overgrazing and undergrazing, depletion of their flora, and reduced productivity of phytocenoses are currently observed. Studying the plant communities of pasture landscapes is relevant because assessing the condition of pasture landscapes and developing land management and ameliorative measures for them contribute to increasing their productivity and preserving landscapes as a whole. The natural fodder lands of the western part of the territory of the Zhanibek and Kaztal districts of the West Kazakhstan region served as the object of the study. The current state of natural pastures and hayfields has been studied, and a landscape-typological classification of pasture landscapes of the research objects has been compiled. Materials from geobotanical surveys have been analyzed. A modern landscape-typological classification of pasture landscapes has been developed, which combines 2 classes of pastures (semi-desert-steppe pastures on light-chestnut and saline soils and steppe pastures on chestnut soils), 4 subclasses of pastures (plain-flat, slightly inclined plane, slightly inclined plane with slightly dissected gully networks, gully-flat), and 14 groups of pasture landscapes, each with a brief description. Within the research objects, 14 groups of pasture landscapes have been identified with descriptions of characteristic plant communities and predominant soils. Natural pasture landscapes have been studied using field and satellite methods. It is recommended to use them as summer-autumn-spring pastures for coarse-haired and fine-haired sheep breeds, large horned cattle, horses, and saigas, and as winter pastures for horses and saigas.

Using the steam distillation method, essential oil samples were obtained from the ground part of Artemisia taurica Willd., which grows wild in the Astrakhan region, and the dependence of its yield on the growing season of the plant was studied. The duration of the steam distillation process was established experimentally based on the study of the dynamics of changes in the yield of essential oil over time. The yield of essential oil was determined in % in terms of the weight of air-dry raw materials. The highest yield of essential oil was obtained from plants in the flowering phase (0.57–0.59%). Quantitative analysis of the main components of Artemisia taurica essential oil was carried out by GC-MS. The quantitative content of essential oil components was calculated from the areas of gas chromatographic peaks without using correction factors. Qualitative analysis was performed by comparing linear retention indices. It has been established that the composition of the essential oil of Artemisia taurica, which grows on the territory of the natural "Bogdinsko-Baskunchaksky" reserve of the Astrakhan region, is very specific. In the essential oil, 41 compounds belonging to various classes have been identified. It includes monoterpene hydrocarbons (6.57%), monoterpenoids (65.17%), sesquiterpene hydrocarbons (4.87%), sesquiterpenoids (1.85%), as well as fatty acids and acid esters (13.93%) and carbonyl compounds (4.04%). The main components of the essential oil are camphor (24.50%), borneol (8.70%), iso-dihydrocarveol (4.11%), mertinal (3.67%), terpene-4-ol (3.35%). Unlike the taxon Artemisia taurica growing in the Crimea, the studied essential oil contains a small amount of a-thujone (1.32%).

Приводятся данные о новых находках 10 видов сосудистых растений, существенно расширяющих сведения об их распространении. Для флоры Туркменистана приводятся 3 вида. Впервые в западной части хребта Кугитанг отмечены Phlomoides kaufmanniana и Origanum tyttanthum. В Юго-Западном Копетдаге обнаружен Ammi majus. Для Западно-Казахстанской области Казахстана впервые приводится Ferula lehmannii, а для Атырауской области – F. karelinii. На юге Российской Федерации впервые для Ростовской области отмечены 2 новых вида (Ofaiston monandrum и Helichrysum nogaicum) и 3 новых вида впервые отмечены для Республики Калмыкия (Stipa cretacea, Arabis auriculata, Astragalus psiloglottis). Нахождение новых таксонов на территории Ростовской области и в Республике Калмыкия может быть связано с недостаточной изученностью флоры. Представительрода Ammi является новинкой для флоры Средней Азии.