Katarina Stojanović

The application of benthic diatoms in water quality assessment (Mlava River, Serbia)

Abstract The main objective of this study was to assess the ecological status of the Mlava River based on epilithic diatoms and to test the use of diatom indices as a tool for estimating the quality of flowing waters in Serbia. Quantitative analysis showed that in April Achnanthidium minutissimum was dominant at each site, except at the fifth site, where Amphora pediculus was dominant. In July and September, Achnanthidium minutissimum, Achnanthidium pyrenaicum, Amphora pediculus, Denticula tenuis, Diatoma vulgaris, Gomphonema elegantissimum, Cocconeis pseudolineata and Cocconeis placentula var. lineata dominated. Detrended correspondence analysis (DCA) was used to detect the major patterns of variation in species composition. The first DCA axis summarizes the distribution of the diatom community, mainly through temperature, conductivity, oxygen and water hardness gradient. The second DCA axis was weakly correlated with few variables. Based on the average values of the pollution sensitivity index (IPS), commission for economical community metric (CEE) and biological diatom index (IBD), the water of the Mlava River belonged to water class I during all three seasons. Values of the diatom-based eutrophication/pollution index (EPI-D) indicated class II water quality. According to calculated trophic diatom index (TDI) values, water of the Mlava River was characterized by intermediate nutrient concentrations during three seasons. Principal components analysis was used to represent the correlation between diatom indices, and the highest correlation among the selected diatom indices is seen between EPI-D, IPS and IBD.

Additional information on the distribution and ecology of the recently described diatom species Geissleria gereckei

Abstract The main objective of this paper is to report new information about the distribution and ecology of a recently described diatom species, Geissleria gereckei. The opportunity for updating the information on the distribution and ecology of the species was provided by the finding of well-developed G. gereckei populations on the lithic material and bryophytes in the Raška and Mlava rivers (Serbia). For several years after the first description, G. gereckei has been known only from the type locality and from another spring in the Dolomiti Bellunesi National Park (the south-eastern Alps). After accurate LM and SEM observations, we provide evidence for the occurrence of the species also in the two above-mentioned rivers in Serbia, as well as in the south-western and south-eastern Alps. After an extensive literature search, it appears that the species is known with certainty only from these sites. Our observations and details from the literature suggest that the species is able to occupy a much broader ecological niche than the very-specific one observed at the time of discovery. The two main determinants for the species’ occurrence appear to be the carbonate nature of the catchments or aquifers, and the ability of the species to be competitive in habitats or microhabitats exposed to seasonal desiccation.

Morphological features of larvae of Drusus plicatus Radovanović (Insecta, Trichoptera) from the Republic of Macedonia with molecular, ecological, ethological, and distributional notes.

Abstract A description of the larva of Drusus plicatus Radovanović is given for the first time. The most important diagnostic characters enabling separation from larvae of the other Drusinae from the southeast Europe are listed. Molecular, ecological, and ethological features and distribution patterns of the species are given. Additionally, information on the sympatric caddisfly species of the three springs where larvae and adults of Drusus plicatus were found and presented.

Benthic diatoms of the Vrla River (Serbia) and their application in the water ecological status assessment

Abstract Epilithic diatoms from the Vrla River (Serbia) have been used to assess the ecological status of water. A total of 227 diatom taxa belonging to 50 genera were identified in the Vrla River during six research seasons with 13 dominant species recorded. Gomphonema (30 species), Navicula (28) and Nitzschia (26) were the most species-rich genera, followed by Pinnularia (12) and Encyonema (11). One taxa was recorded as new to Serbia – Geissleria acceptata. CCA grouped the diatom taxa into three main groups. The first group included taxa found at most of the sampling sites, the second group involved diatom taxa significantly positively correlated with the oxygen, while the third group showed positive correlation with temperature. RDA showed that some diatom taxa, including: Cocconeis placentula var. placentula, C. placentula var. lineata, C. pseudolineata and Mayamaea atomus var. permitis, are significantly positively correlated with temperature, while others, for example Achnanthidium minutissimum, Hannaea arcus, Nitzschia pura are mostly correlated with total phosphorus, alkalinity and water hardness. The ecological status of the Vrla River ranged from moderate, good to high. It was shown that according to the diatom indices, the ecological status of water downstream and upstream of a trout fish pond was slightly different.

Ithytrichia Eaton, 1873 (Hydroptilidae: Trichoptera): A Genus New for the Entomofauna of Serbia

ABSTRACT: During field work carried out in 2003, 2004, 2007, and 2011, larvae of the genus Ithytrichia (Trichoptera, Hydroptilidae) were identified as part of a benthic macroinvertebrate survey. Specimens of Ithytrichia lamellaris Eaton, 1873 were collected from independent localities in four rivers of Eastern and Central Serbia, namely the Black Timok, Mlava, Morava, and Western Morava. For the fauna of Serbia, three species within the family Hydroptililae were known up to now: Hydroptila vectis, Hydroptila sparsa, and Agraylea multipunctata. This is the first record of Ithytrichia larvae in watercourses of Serbia (Danube basin). Analysis of the environmental data indicates that I. lamellaris is a typical eurythermic species which inhabits slightly alkaline waters rich in dissolved oxygen, with a moderate organic load and abundant aquatic vegetation.

Uncertainty of using habitat fidelity in biomonitoring based on benthic diatoms - the Raška River case study

Epilithic diatoms are frequently recommended for river biomonitoring, while much less emphasis is placed on epiphytic communities. This study considers use of epiphytic and epilithic diatom communities from the Raška River in biomonitoring. A total of 212 diatom taxa were recorded in both communities. Dominant diatoms were Achnanthidium minutissimum (Kützing) Czarnecki, A. affine (Grunow) Czarnecki, A. subatomus (Hustedt) Lange-Bertalot, Amphora pediculus (Kützing) Grunow, Diatoma vulgaris Bory, Gomphonema tergestinum (Grunow) Fricke, Cocconeis placentula var. lineata (Ehrenberg) Van Heurck, Melosira varians Agardh and Navicula tripunctata (Müller) Bory. Redundancy analysis (RDA) was used to detect the relationships between diatoms, some environmental factors and sampling sites. Diatoms of the epiphytic community showed a clearly grouping in relation to the sampling sites as compared with diatoms of the epilithic community. Species common to both communities showed a similar correlation with some environmental variables (BOD, pH, NH4+, TP, NO3− and conductivity), with three exceptions (Diatoma vulgaris, Cymbella compacta, and Encyonema silesiacum). Pearson’s correlation coefficient showed correlation between selected environmental variables and diatom indices calculated using OMNIDIA 6.2 software (TDI, IPS, CEE, GENRE, TID, SID, SHE and IDSE/5). Diatoms of the epiphytic community are more clearly clustered in relation to the sampling sites as compared with diatoms of the epilithic community. According to our results there is still “place” in biomonitoring for epiphytic community. The present study highlights the necessity of sampling both epiphytic and epilithic communities because substrate specificity could play important role in biomonitoring.

The trout farm effect on Dinocras megacephala (Plecoptera: Perlidae) larvae: Antioxidative defense

Trout production represents a major agricultural activity in Serbia. Organic compounds are drained into the environment, usually without previous sedimentation, thus affecting the stream biota. Considering that biological monitoring is commonly based on aquatic macroinvertebrates as target organisms, the authors used larvae of Dinocras megacephala to estimate trout farm effects on the mass of the larvae and their antioxidative defense in pollution stress conditions. Four locations were chosen along the channel of the Raška River, 2 upstream (L1, L2) and 2 downstream (L3, L4) from the trout farm outlet. Basic physical and chemical water parameters were measured. Superoxide dismutase (SOD) and catalase (CAT) activity changes were analyzed to determine the level of oxidative stress caused by the increase of organic compounds originating from the trout farm. Dissolved oxygen concentration decreased from the upstream to downstream locations. Furthermore, the concentration of ionized ammonia was almost 10 times higher at the downstream locations than at the upstream locations. Larval mass, as well as CAT activity, was significantly higher at L3 compared with the other 3 locations. Activity of SOD was significantly higher at L3 than at L1. The results indicate that higher concentrations of organic compounds from the trout farm induce clear changes in the status of the antioxidant defense of D. megacephala larvae. Environ Toxicol Chem 2016;35:1775-1782.

Phylogeography of the southern medicinal leech, Hirudo verbana: a reply to Utevsky and Trontelj (2015)

Medicinal leeches (Hirudo spp.) are among the best studied of animals as far as their morphology, physiology, and behavior are concerned (Sawyer 1986), but for a long time their taxonomy was neglected (Trontelj and Utevsky 2005). The taxonomy, genetics, and distribution of these famous animals were resolved just in the last decade (Trontelj et al. 2004; Trontelj and Utevsky 2005; Siddall et al. 2007; Utevsky et al. 2010; Elliott and Kutschera 2011; Kutschera 2012; Trontelj and Utevsky 2012). Trontelj and Utevsky (2012) investigated the phylogeny and phylogeography of Hirudo verbana, H. medicinalis, and H. orientalis and determined only little genetic differentiation within species, except in H. verbana, which is ‘‘subdivided into an eastern phylogroup (southern Ukraine, North Caucasus, Turkey, and Uzbekistan) and a western (Balkans and Italy) phylogroup.’’ We (Živic et al. 2015) performed a molecular characterization of the genus Hirudo on the territory of Serbia by sequencing the mitochondrial cytochrome oxidase subunit I (COI). All analyzed specimens belonged to the eastern phylogroup of Hirudo verbana as defined by Trontelj and Utevsky (2012). In interpreting the results, we wrote: ‘‘genetic differentiation of the species H. verbana into eastern and western clades, as proposed by Trontelj and Utevsky (2012), is unrealistic.’’ This prompted Trontelj and Utevsky to reanalyze sequence data from both studies (Trontelj and Utevsky 2012, Živic et al. 2015). Their response is of interest to both groups of authors, and more importantly, it is of interest to science itself. The obtained results unequivocally support the subdivision ofH. verbana into two phylogroups, eastern and western. In our paper, we did not want to dismiss the subdivision itself, but to say that the border between the phylogroups is not realistic. However, the unfortunate choice of words was misleading. Our true intentions can be clearly seen in the part of the discussion dealing with the biogeography of H. verbana, where we propose almost the same division of the H. verbana area as that given by Trontelj and Utevsky in their response to our paper, with the border between the phylogroups significantly shifted to the west compared to the one put forward by them earlier (2012): ‘‘... all specimens determined as the western clade (Trontelj and Utevsky 2012) belong to the North and South Adriatic regions, while our specimens belong to the Pontic province. Differences between the western (Ionian, South Adriatic, Neretva Watershed, and North Adriatic) and eastern (Atticobeotia, Aegean, and Pontic) regions with respect to their freshwater faunas have already been documented for Handling Editor: Piet Spaak.