First record of Eurytemora velox (Lilljeborg, 1853) (Crustacea: Copepoda: Calanoida)... 35 Historia naturalis bulgarica, 17: 35-38, 2006 First record of Eurytemora velox (Lilljeborg, 1853) (Crustacea: Copepoda: Calanoida) in Iceland with morphological notes Ivan PANDOURSKI, Vesela EVTIMOVA PANDOURSKI I., EVTIMOVA V. 2005 First record of Eurytemora velox (Lilljeborg, 1853) (Crustacea: Copepoda: Calanoida) in Iceland with morphological notes. – Historia naturalis bulgarica, 17: 35-38. Abstract. The calanoid copepod Eurytemora velox is reported for the first time in Iceland from the Bessastaðatjörn Lake. This is the dominant crustacean species in the littoral zooplankton. The morphological features in the specimens concerning the shape and ornamentation with spines and fine short setae of leg 5 in females and males vary. Asymmetry in the spine ornamentation on the ultimate segment of leg 5 in two females was observed. Key words: Eurytemora velox, Copepoda, Iceland, Morphology Introduction In the summer of 2004 (June – July) we conducted faunistic studies on the zooplankton in shallow coastal water bodies on the Reykjanes Peninsula and the surroundings of the city of Reykjavik. Despite the considerable inflow of fresh water from the numerous streams and rivers, a greater part of these water bodies are brackish and directly influenced by the ocean tides. In one of these lakes, Bessastaðatjörn, we found a dense population of Eurytemora velox (Lilljeborg, 1853). Freshwater and brackish calanoids are still not very well studied in Iceland. Up to date there are records of only four species of the family Diaptomidae (SCHER et al., 2000). Previously the genus Eurytemora Giesbrecht, 1881 has been reported from Iceland with only one species, Eurytemora americana Williams, 1906, found in typical marine biotopes on the north coast of Iceland (JESPERSEN, 1940). Eurytemora velox is widely distributed in the brackish waters from the Arctic Ocean and the Baltic Sea shore to South-eastern Europe, the Sea of Azov and the Caspian Sea (VRANOVSKÝ, 1994). In this paper we present data concerning an isolated population of this species, 1400 km away from the Scandinavian Peninsula and about 1100 km away from the British Isles. Study site The zooplankton samples were collected from Bessastaðatjörn Lake (64°7‘N 22°0‘W), situated on the Álftanes Peninsula, 6 km south of Reykjavik, SW Iceland. Bessastaðatjörn Lake is a brackish coastal shallow lake, with coarse volcanic sand bottom and pH of 8.5. The small depth of the lake and the frequent strong winds determine its holomictic character. The ocean coast proximity and the