A new species of Acroperus Baird, 1843 (Cladocera: Chydoridae) is described based on the material from Lake Tana, Ethiopia and two water bodies in Eastern Cape, Republic of South Africa. In Africa, Acroperus africanus sp. nov. had a chance to be confused by previous authors with Palearctic A. harpae (Baird, 1834) and A. angustatus Sars, 1863, but it could be easily distinguished from the latter by: (1) smaller seta on the proximal segment of antenna II endopod; (2) larger values of seta 3/seta 2 length ratio on the limb I, as well as some additional features. Diversity of the genus in Africa is underestimated yet, and further investigations of taxon distribution and ecology are necessary.

A comparison between populations of the diaphanus-group of Leberis Smirnov, 1989 from Australia and India confirmed that Australian L. diaphanus (King, 1853) and Indian L. punctatus (Daday, 1898) are separate species. Morphology of parthenogenetic females of L. punctatus is redescribed for the first time. Some fine details of morphology are re-examined in other species of Leberis, taxonomically significant features and their variability are studied. In the Old World L. punctatus could be confused with L. diaphanus, but the former differs from the latter mainly in the details of thoracic limbs I and IV. Both species have relatively broad distribution ranges: L. punctatus inhabits South Asia, Africa and penetrates Southeast Asia, L. diaphanus is a widespread taxon in the water bodies of Australia, Southeast Asia and South China. Diversity of the genus in the Old World is underestimated yet, and further investigations are desirable.

Pleistocene water bodies have been studied using the paleolimnological approach, which traces environmental changes using particular subfossils as ecological proxies, rather than analysis of the paleocommunities themselves. Within a given taphocoenosis, the presence and quantity of animals are related to environmental conditions rather than to community types where relationships between taxa are stabilized during their long-term co-occurrence and are (at least partially) more important than the particular environmental conditions at the time of deposition, which may have experienced significant seasonal and inter-seasonal variations. Here, we analyze Branchiopoda (Crustacea) of two paleolocalities in the Transbaikalian Region of Russia: Urtuy (MIS3) and Nozhiy (older than 1.5 million years). Cladocerans Daphnia (Ctenodaphnia) magna, D. (C.) similis, D. (Daphnia) pulex, Ceriodaphnia pulchella-reticulata, C. laticaudata, Simocephalus sp., Moina cf. brachiata, M. macropopa clade, Chydorus cf. sphaericus, Capmtocercus sp. and anostracans Branchinecta cf. paludosa, and Streptocephalus (Streptocephalus) sp. are found in two localities. With the exception of the last taxon, which now occurs in the southern Holarctic, all other taxa inhabit the Transbaikalian Region. Within Eurasia, the steppe zone has the greatest diversity of large branchiopods and a high diversity of some cladocerans, such as subgenus Daphnia (Ctenodaphnia) and Moina sp. Here we demonstrated that the branchiopod community in shallow steppe water bodies has been unchanged since at least the Pleistocene, demonstrating long-term morphological and ecological stasis.

Species of the genus Ceriodaphnia Dana, 1853 (Crustacea: Cladocera: Daphniidae) are present in the plankton of many freshwater bodies all around the World. However, the taxonomy of the genus is still poorly developed. Most species have been described in the nineteenth century and data on their morphology and distribution should be revised according to current standards. Currently, due to lack of reliable morphological and genetic data, almost all nominal species of Ceriodaphnia are considered as species groups rather than separate biological species, complicating the detection and description of new species of the genus. Here, we redescribe the morphology of Ceriodaphnia quadrangula (O.F. Müller, 1785) based on material close to the type locality in Denmark, and describe a new species of Ceriodaphnia from the Mediterranean region. Also, we provide a phylogenetic analysis using existing and novel sequences of mitochondrial DNA of the commonest species of the genus. Ceriodaphnia smirnovi sp. nov. can be easily distinguished from C. quadrangula via presence of the head pore and the structure of the second thoracic limb, the postabdomen and the ephippium. From other species of Ceriodaphnia known to date C. smirnovi sp. nov. can also be separated on ephippium structure and some other fine morphological features. Although distribution range of C. smirnovi sp. nov. must be clarified in the future based on analysis of more sampling points, most likely, it is restricted to the Mediterranean region. The phylogenetic analyses showed high divergence among 16 different clades (mean clade separation of 13±2.3 % (mean ± SD) and 20.7±2.1% for 16S and COI respectively). These clades belonged to 11 described species and 5 undescribed. The high intraspecific variability of some species indicates the possible existence of more undescribed species within present species groups.

The aim of this paper is to study the species composition, structure and seasonal dynamics of the cladoceran fauna and species associations in inland water bodies of Jeju Island (Republic of Korea). Only 47 taxa were found in 199 samples. Such faunal paucity could be explained by the existence of only a few types of aquatic environments on Jeju Island as compared to continental China and the Far East of Russia, with their great diversity of water types. We have demonstrated a high significance of the tropical species on Jeju. Our data confirm seasonal faunistic changes in the continental waters of Jeju Island. The rate of tropical taxa is highest in September, after the monsoon season, while the Far Eastern endemic taxa are more common in winter. At the same time, the contribution of Boreal taxa to the fauna of the island is low even in winter. Species associations have been revealed based on binominal distribution; they change significantly from summer to winter. However, a contribution of Boreal taxa to the species associations also is minimal (even in winter), whereas tropical taxa contribute to them greatly (including in winter). We can propose a rough scheme of faunal formation exploring the whole set of obtained information. Initially, at the earlier stages of the island formation, its fauna was consisted of some pre-Pleistocene taxa. Then, during the Pleistocene time, Jeju Island was secondarily interconnected with more southern territories, and tropical species have colonized it. Recent Boreal cladoceran invaders arrived at the island water bodies later when they were already inhabited by formed associations, and for this reason only few of them were able to settle down there. Such a scheme is a hypothesis which needs to be checked by the future phylogeographic studies.