Ahmet Bozkurt

TWO NEW RECORDS OF HARPACTICOID COPEPODS FOR TURKISH INLAND WATERS (COPEPODA, HARPACTICOIDA) PHYLLOGNATHOPUS VIGUIERI (MAUPAS, 1892) AND LEPTOCARIS BREVICORNIS (VAN DOUWE, 1904)

The harpacticoid copepods, Phyllognathopus viguieri (Maupas, 1892) and Leptocaris brevicornis (Van Douwe, 1904) are reported for the first time from, respectively, the lakes Golbasi and Golkent. This is the first record of these two species for inland waters of Turkey. Males and females of Phyllognathopus viguieri and Leptocaris brevicornis were consistently found during two sampling periods. In addition, 13 other species of copepods species were found in the two lakes.

First record of the epibiont protozoan Epistylis sp. on zooplankton (Copepoda, Cladocera, and Rotifera) from the Asi River, Turkey

Based on preliminary evidence (collected by us early 2005) of Epistylis infection of zooplankton, we investigated the prevalence of epibionts on various groups of metazooplankton with regard to Epistylis in the Asi River, north-eastern Mediterranean, Turkey. This study presents a detailed record of that ciliate protozoan on zooplankton from the Asi River in 2005-2006. Copepods, cladocerans, and rotifers were monthly sampled in the study period. The colonial Epistylis sp. was found on various groups: rotifers were the most abundant metazooplankton group (58 species out of a total of 89 zooplankton species) but the results show that copepods are the preferred substratrum for Epistylis sp., followed by cladocerans and rotifers. The highest densities of infected zooplankton were observed in December (116 ind. 20 L−1), then in May (92 ind. 20 L−1). Also October (91 ind. 20 L−1), and November (83 ind. 20 L−1) were associated with high zooplankton densities, possibly due to the increase in adhesion surface. The density of infected zooplankton was found to be positively correlated with zooplankton richness. The zooplankton infection in the Asi River constitutes the first record for Turkish inland waters of Epistylis sp., with the exception of a previous record for Cyclops vicinus Uljanin, 1875. A partir de la mise en evidence preliminaire de linfection du zooplancton par Epistylis (collecte par nous-meme debut 2005), nous avons recherche la prevalence depibiontes sur divers groupes de metazooplancton pour evaluer linfection par Epistylis dans la riviere Asi, Mediterranee nord-orientale, Turquie. Cette etude presente un signalement detaille de ce protozoaire cilie sur le zooplancton de lAsi en 2005-2006. Les copepodes, les cladoceres et les rotiferes ont ete echantillonnes chaque mois au cours de la periode detude. Lespece coloniale Epistylis sp. a ete trouvee sur differents groupes: les rotiferes etaient le groupe de metazooplancton le plus abondant (58 especes sur un total de 89 especes du zooplancton), mais les resultats montrent que les copepodes sont le substrat prefere dEpistylis sp., suivis des cladoceres et des rotiferes. Les densites les plus elevees de zooplancton infectes ont ete observees en decembre (116 ind. 20 L−1), puis en mai (92 ind. 20 L−1). De meme octobre (91 ind. 20 L−1), et novembre (83 ind. 20 L−1) etaient associes aux densites elevees de zooplancton, peut-etre en raison de laugmentation de la surface dadhesion. La densite de zooplancton infecte a ete trouvee liee positivement a la richesse en zooplancton. Linfection du zooplancton dans lAsi constitue le premier signalement dEpistylis sp. dans les eaux interieures de Turquie, avec lexception dun premier signalement pour Cyclops vicinus Uljanin, 1875.

Seasonal variations in the length of zooplankton related to certain physicochemical variables in two freshwater reservoirs

Seasonal variations in the body length of zooplankton were studied in relation to water temperature, nitrate (NO3), soluble reactive phosphorus (SRP), total chlorophyll, Secchi disk depth, pH, conductivity, and oxidation-reduction potential (ORP) in a mesotrophic (Ikizcetepeler) and a eutrophic (Caygoren) reservoir from February 2007 to March 2008. During the study, the body lengths of a total of 7590 zooplankton specimens (1110 rotifers, 3270 cladocerans, and 3210 copepods) were measured. The length of the majority of the species was significantly smaller in summer than in winter, fall, and spring, including that of the most dominant species, Asplanchna priodonta, Daphnia galeata, Daphnia longispina, Diaphanosoma brachyurum, Bosmina longirostris, Leptodora kindtii, Ceriodaphnia pulchella, Cyclops vicinus, Metacyclops gracilis, and Acanthocyclops robustus (F > 5, p < 0 . 05 ). Correspondence analysis (CA) showed that the body length of the zooplankton studied was inversely related to water temperature, whereas it was positively related to ORP and pH. The results of our study suggest that, although nutrients (NO3 and SRP) apparently have an effect on zooplankton body length only in the mesotrophic reservoir, temperature influences the body length in both the mesotrophic and the eutrophic reservoir.