Comparative study of the genotoxic response of freshwater mussels Unio tumidus and Unio pictorum to environmental stress

Genotoxic response of freshwater mussels U. tumidus and U. pictorum to environmental stress was studied using comet assay on hemocytes and gill cells. The mussels were acclimated to controlled laboratory conditions for 10 days, and then exposed at 4 sites in the Sava and Danube rivers in the area of the city of Belgrade. Samples of each species were taken after 7, 14, and 30 days of exposure. The mussels sampled immediately after acclimation served as controls. Genotoxic response in both species was induced earlier at sites receiving untreated wastewaters from the city’s main collectors (7 days), than at the site receiving only domestic wastewaters from small settlements located upstream from the city (30 days). There was a correlation between the comet tail intensity values in tissues of exposed mussels and the concentrations of zinc, copper, iron, and arsenic at the exposure sites. The genotoxic responses in both tissues of U. pictorum and in hemocytes of U. tumidus were similar, while U. tumidus gill cells failed to exhibit significant genotoxic response at two sites. These findings, together with higher mortality of U. tumidus at the most polluted sites, promote U. pictorum as a model for genotoxicity monitoring in freshwater environments.     

When do meadow vipers (Vipera ursinii) become sexually dimorphic? – ontogenetic patterns of sexual size dimorphisms

Contrary to an increasing number of papers that document sexual dimorphism in size (and/or shape) in adults, studies dealing with sex differences in newborn and juvenile snakes are surprisingly scarce. Data about ontogenetic shifts in sexual dimorphism are generally lacking and hence, it is unclear whether sex differences are set at birth or arise post‐natally. In this study, we analyzed patterns of sexual dimorphism in body size, head dimensions and tail length (TL) among newborn, subadult and adult meadow vipers (Vipera ursinii) from the Bjelasica Mt. in Montenegro. Patterns of sexual size dimorphisms differed among traits. There was no significant difference in head dimension of males and females, but adult snakes were sexually dimorphic in body size. Sexual differences in TL were evident since birth but changed in degree throughout ontogeny. Neonate meadow vipers presented highly significant inter‐litter variation in the sexual dimorphism of all traits we have measured. Such family effects may have an important influence on extent of inter‐sexual differences in snakes and should be included in analyses of sexual dimorphism.     

Richness and diversity of Pontic flora on serpentine of Serbia

Serpentine substrate in Serbia covers wide areas mainly in Kosovo and in central, western and south-western part of the country. On the serpentines of Serbia, particularly on the skeleton soils of hills and on lower elevation mountain slopes, there are some xerophilous and steppe-like vegetations. These xerophilous grasslands include mostly Pontic, Pontic-Submediterranean and/or Mediterranean-Submediterranean-Pontic plants. The distribution of 161 taxa of Pontic, Pontic-Submediterranean and Mediterranean-Submediterranean-Pontic areal — types on serpentinites of Serbia was analyzed in order to distinguish centers of richness and diversity. The distribution of taxa was analyzed with respect to geographic, ecological and climatic factors. The qualitative composition of Pontic flora on the serpentine areas was also compared. The greatest floristic richness and the center of diversity of Pontic flora on serpentine of Serbia was recorded in central part of the area investigated.     

Low genetic diversity and contrasting patterns of differentiation in the two monotypic genera Halacsya and Paramoltkia (Boraginaceae) endemic to the Balkan serpentines

Halacsya and Paramoltkia are two monotypic genera of the Balkan ultramafic outcrops, both classified as paleoendemics. They show close phylogenetic relationship, similar ecology and partially sympatric range, but contrasting life-history traits, patterns of distribution and chromosomal features. We performed a study to compare their infraspecific genetic structure using AFLP fingerprinting. Within-population heterozygosity (H_S) and total heterozygosity (H_T) were lower in diploid H. sendtneri than in polyploid P. doerfleri (0.121 and 0.142 vs. 0.165 and 0.178, respectively). Number of polymorphic loci was also higher in the latter species. Halacsya showed significant levels of among-population variation (14.5%) and population differentiation (F_ST = 0.145), as well as a structuring in four main geographic groups connected by low gene flow. Combined with inability for long-distance dispersal, these data suggest that present-day range fragmentation in this species is the result of historical losses of intervening populations and support its status of paleoendemic surviving in refugial serpentine “islands”. Populations of P. doerfleri were instead genetically very close (F_ST = 0.049), and variation was partitioned almost exclusively among individuals (95.1%). Lack of population groupings and higher levels of gene flow suggested a single, panmictic group, fitting more a metapopulation than a “classical” paleoendemic model.     

Oligochaeta of the Danube River — a faunistical review

The aim of this work is to discuss the distribution of Oligochaeta (Annelida) in the Danube River using the collections made by the Joint Danube Survey 2007 (JDS2) on more than 2800 km of the river. The basic faunistical features of the oligochaete assemblages were analysed with regard to three main sectors of the Danube (upper, middle and lower reaches, the last with the Danube Delta). A total of 52 oligochaete taxa have been recorded. Most of the observed species are typical of the potamon-type rivers in the region, and are well adapted to moderate-to-high organic load. The highest taxa richness and frequency of occurrence were observed among the Tubificidae family. Naididae, Propappidae, Enchytraeidae and Haplotaxidae had also low frequency. The upper reach of the Danube showed the lowest species richness, while the middle reach is characterised by its highest species richness. Construction of dams and regulation of the riverbed have resulted in an increase of limno(rheo)philic taxa which prefer slow-flowing and lentic zones.     

<Emphasis Type="Italic">Cardamine amara</Emphasis> (Brassicaceae) in Serbia and Republic of Macedonia

Distribution data on Cardamine amara L. in Serbia and Republic of Macedonia are presented, together with a short review of the history of taxonomic treatment of C. amara in this area. C. amara subsp. balcanica Marhold, Ančev & Kit Tan is reported as a new taxon both for the flora of Serbia and flora of Republic of Macedonia and the occurrence of C. amara subsp. amara in Serbia was confirmed.     

Stipa crassiculmis subsp. picentina (Poaceae) new for the Balkans – a further example of amphi-Adriatic disjunction

Stipa crassiculmis subsp. picentina Martinovský, Moraldo & Caputo (Poaceae, Pooideae, Stipae) was found for the first time in the Balkan Peninsula. It was recorded in the northern part of the Republic of Macedonia, in the P?inja River gorge (Badar Gorge), between Veles and Katlanovo on ultramafic substrates. To date, S. crassiculmis subsp. picentina was known only for Italy where it occurs in the Lombardy and Campania administrative regions. This record for the Balkan Peninsula is a new example of Amphi-Adriatic Balkan-Apennine disjunction. In this paper, the morphological and anatomical characters of the specimens collected in the study area were reported together with the phytosociological characteristics of the habitat. The threatened status of the species for Macedonia was also assessed on the basis of the IUCN criteria.