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[Aim] The afroalpine sky-islands present one of the most interesting models to study discrete biogeographic patterns in a terrestrial island system. Here, we performed range-wide sampling of the afroalpine clade of fine-leaved Festuca grasses and address a set of hypotheses on its origin and dispersal. We focus on the widespread species F. abyssinica and explore the role of the eastern and western African sky-islands., [Location] Tropical Africa, [Taxon] Afroalpine Festuca, [Methods] We combine data from field surveys, phylogeography, coalescence-based dispersal modelling, and environmental niche and dispersal costs analyses to infer patterns of genetic diversity, genealogical relationships, colonization routes and range shifts under two Quaternary climates (current – to represent warm periods; and Last Glacial Maximum (LGM) – to represent cold periods)., [Results] The westernmost populations in East Africa show higher genetic diversity and higher similarities with the West African populations and the Ethiopian Simen Mountains than with the more closely situated East African populations. Dispersal models and ecological niche predictions of F. abyssinica supported multiple long-distance dispersals (LDD) among the eastern African sky-islands, and at least two dispersal events between the two sides of Africa (0.86 Ma and 0.52 Ma), probably facilitated by bridging suitable habitats during the coldest periods of the Pleistocene., [Main conclusions] We reconstruct an afroalpine mountain-hopping dispersal model, with migrations occurring between adjacent sky-islands in eastern Africa, and through a Central Africa–Sudan pathway connecting afroalpine patches on the two sides of the continent., The work was supported by the Spanish MINECO CGL2012-39953-C02-01 and the Norwegian NUFU 2007/1058 grant projects to PC and CB respectively. MN was funded by a Spanish Ministry of Education postdoctoral contract in the University of Zaragoza, and PC and MN by a Bioflora research team A01-17 and A01-20R grants co-funded by the Spanish Aragón Government and the European Social Fund (FEDER 2014-2020; "Construyendo Europa desde Aragón").

The sterlet (Acipenser ruthenus Linnaeus, 1758) is a relatively small sturgeon widely distributed in Eurasian rivers from the Danube to the Yenisei. During the twentieth century, all wild sterlet populations have declined due to anthropogenic factors including: overfishing, poaching, construction of dams, and pollution. Despite the necessity of characterization both wild and captive stocks, few studies of population genetics have been performed thus far. Here we studied the genetic diversity and geographic structure of sterlet populations across the eastern range – Ob-Irtysh and Yenisei basins – by sequencing a 628-bp fragment of mitochondrial DNA control region. We identified 98 new haplotypes, delineated 12 haplogroups and estimated the time of basal haplogroup divergence within the species as over 8 million years ago. Our data suggest that Ob-Irtysh and Yenisei populations are isolated from each other and much lower genetic diversity is present in the Yenisei population than in the Ob-Irtysh population. Our data imply that sterlet populations in Siberian rivers underwent bottleneck or fragmentation, followed by subsequent population expansion. The data obtained here are important for sterlet population monitoring and restocking management.

Проанализирован полиморфизм контрольного региона мтДНК Urocitellus undulatus для изучения филогеографии и генетической структуры вида в Алтае, Туве, Монголии, Бурятии и Байкальском регионе. Анализ 104 образцов из 16 популяций выявил 5 групп гаплотипов. Две из них представляли восточные популяции из Байкальского ареала и Восточной Монголии, две группы занимали центральную область (Западная Бурятия, Центральная и Западная Монголия и Тува), а последняя представляла западные популяции с Алтая., We analyzed the polymorphism of the mtDNA control region in Urocitellus undulatus to study phylogeography and genetic structure of this species in Altai, Tuva, Mongolia, Buriatia and Baikal region. Analysis of 104 samples from 16 population revealed 5 groups of haplotypes. Two of them represented eastern populations from Baikal area and Eastern Mongolia, two groups occupied central area (Western Buriatia, Central and Western Mongolia and Tuva), and the last one represented the western populations from Altai

Филогенетическая структура представителей рода Neogobius была изучена на основе анализа изменчивости гена цитохрома b. Показаны значительные различия в уровне дивергенции между черноморскими и каспийскими популяциями N. fluviatilis и N. melanostomus. В качестве основной причины формирования наблюдаемой картины дивергенции рассматривается серия геоморфологических преобразований Понто-Каспийского бассейна., Phylogenetic structure of the genus Neogobius is studied by analyzing of the variability of cytochrome b. Significant differences in the level of divergence between the Black Sea and the Caspian population of N. fluviatilis and N. melanostomus are showed. As the main reason for the formation of the observed pattern of divergence a series of geomorphic change of the Ponto-Caspian basin is considered.