This study introduces a technique to uncover concealed patterns in satellite altimetry data, reflecting sea level variations in inland water bodies. We applied the methodology to the Caspian Sea, using altimetry data from four satellite missions over 27 years (1993-2020): TOPEX/Poseidon, Jason1, Jason2, and Jason3. The approach involves two steps: estimating sea level trends and identifying breakpoints that indicate trend shifts; and leveraging time lags between breakpoints at various locations to classify water drainage areas according to their degree of influence on each period. By revealing concealed patterns in the altimetry data, this technique can provide insights to understand the impacts of global warming and local climate changes on sea level fluctuations in the Caspian Sea. We hope that our study can facilitate subsequent interdisciplinary research on the intricate interplay between climate change and hydrological processes in inland water bodies.

The Ponto-Caspian region is the main donor of invasive amphipods to freshwater ecosystems, with at least 13 species successfully established in European inland waters. Dikerogammarus spp. and Pontogammarus robustoides are among the most successful, due to their strong invasive impact on local biota. However, genomic knowledge on these invaders is scarce, while phylogeography and population genetics have been based on short fragments of mitochondrial markers or nuclear mi-crosatellites. In this study, we provide: (i) reconstruction of four mitogenomes for four invasive gammarids; (ii) comparison between the structure of the newly obtained mitogenomes and to those from literature; (iii) SNP calling rates for individual D. villosus and D. haemobaphes from different invasion sites across Europe; and (iv) the first time-calibrated full mitogenome reconstruction of several Ponto-Caspian taxa. We have sequenced, assembled and annotated four mitogenomes, each from D. villosus, D. hae-mobaphes, D. bispinosus and Pontogammarus robustoides. We found that, in comparison to other gammarids, the mitogenomes of Ponto-Caspian species show a translocation between the tRNA-E and tRNA-R positions. Phylogenetic reconstruction using the mitogenomes identified that Ponto-Caspian gammarids form a well-supported group that originated in the Miocene. Our study supports paraphyly in the family Gammaridae. These mitogenomes serve as vital genetic resources for the development of new markers for PCR-based identification methods and demographic studies.

To fill in the blanks for charophytes in the Caucasus to improve our knowledge of species distribution areas in Eurasia, a field survey and study of available specimens from Dagestan (North Caucasus, Russia) was conducted based on morphological observation and molecular genetic analysis. Seventeen new localities for six Chara species and one Tolypella species, with six new species and one new genus for the region studied, and one new species for the Caspian Sea region were found. Some species records changed the outline or filled in the gaps in the species distribution area. The presence of species with a distribution area mainly in the centre of Eurasia (C. globata, C. neglecta) with mainly Mediterranean – Middle East species (C. gymnophylla) is notable for this region, as well as for other studied regions of the Caucasus having a combination of species with different distribution areas. The frequent occurrence of C. gymnophylla points is similar to that in the Mediterranean region and the Middle East. Small brackish waterbodies at the coast of the Caspian Sea, freshwater mountain rivers, small waterbodies associated with them, and water reservoirs are the main habitats of charophytes in the regions. The habitat preference and distribution in the Caucasus allowed suggestion some species for protection. The absence of endemic species among charophytes from Dagestan and Caucasus contrasts with the flora of terrestrial magnoliophytes, which have a large number of endemic species.