Bojana Stojanovic

Macroinvertebrates along the Serbian section of the Danube River (stream km 1429–925)

Results of the investigation of the aquatic macroinvertebrate fauna along a 504 km stretch of the Danube River in Serbia are presented. A total of 74 macroinvertebrate taxa were observed during a 2001 survey. Oligochaeta and Mollusca were the principal components of the community with regard to species richness and abundance. Based on data on the qualitative composition of the macroinvertebrate fauna, a correspondence analysis divided the investigated stretch in three sectors — upper (Pannonian), Iron Gate sector and entrance sector to the Iron Gate stretch. The distribution patterns of certain species supported the division of sectors defined by correspondence analysis.

DISTRIBUTION OF NON-INDIGENOUS TUBIFICID WORM BRANCHIURA SOWERBYI (BEDDARD, 1892) IN SERBIA

ABSTRACT Recently, dispersion of invasive species became an important theme, since the man-aided outspread of the organisms was recognized as one of the major threats to the biodiversity. Aquatic biotopes are, due to its unique features, among the most disposed ecosystems to this kind of disturbance. Non-indigenous species of different origin were found among plants, vertebrates and invertebrates. Aquatic worm Branchiura sowerbyi (Beddard 1892) is obvious example of human induced dispersal of invertebrates. The aim of the study was to contribute to the cognition of the current distribution of this invasive species and to point up, once again, the risk of devastation of aquatic ecosystems caused by distribution of alien species. B. sowerbyi was for the first time observed in Serbia in 1972 in fish pond in Vojvodina. Since that time the worm spread its areal and now it could be found in a lot of ponds, channels, reservoirs and lowland rivers in Serbia. According to our results B. sowerbyi has been well adapted in artificial and modified water bodies in Serbia.

A NEW RECORDS OF EPEORUS YOUGOSLAVICUS (ŠAMAL, 1935) (EPHEMEROPTERA) IN SERBIA AND MONTENEGRO

ABSTRACT During hydrobiological investigations of diversity of rivers and brooks of Serbia and Montenegro, new records of Ephemeroptera species, Epeorus yougoslavicus (12) was ascertained, in period from 2000 to 2005 years. The find of this species, except that it enriches diversity of Ephemeroptera fauna of Serbia and Montenegro, is also important for knowledge of distributions of this species. New biotopes of this species in Gobeljska River on Kopaonik Mountain represents the most northward border of its areal, known until now. On all bitopes where it was found in Serbia and Montenegro, the species occurs in very rare populations, that is a case and with its other until now known finds on Balkan and Apennine peninsula. Small populations and mutually isolated bitope can be taken as parameters on which this species can be consider as endangered for territory of Serbia and Montenegro.

A New Record of Choroterpes Picteti (Eaton, 1871) [Ephemeroptera: Leptophlebiidae] in Serbia

ABSTRACT C. picteti is widely distributed species in the Europe, but, due to the stenovalent character of the species, as well as destruction of relevant aquatic habitats, it has been characterized as rare and endangered species. This finding indicates, once again, that Serbian mayfly (Ephemeroptera) fauna is still not completely known and detailed surveys are needed. Serbian streams are renowned for their diverse fauna, although specific knowledge about the taxa inhabiting them is scarce, that include mayfly fauna too. Insect fauna of small streams of mountainous region of Serbia (north from the Danube) are especially diverse and reports of new species for fauna of Serbia are expected. The first record of Choroterpes picteti (Eaton, 1871) for Serbia is reported in this research.

DISCOCOTYLE OHRIDANA N. SP. (MONOGENEA: DISCOCOTYLIDAE) ON THE GILLS OF OHRID BELVICA SALMOTHYMUS OHRIDANUS (PISCES: SALMONIDAE) FROM THE LAKE OHRID, MACEDONIA

ABSTRACT Discocotyle ohridana n.sp. is described from the gills of Ohrid belvica Salmothymus ohridanus Steindachner, 1892; (syn. Acantholingua ohridana Hadzisce, 1961) from the Lake Ohrid, Macedonia. According our investigation the new species D. ohridana n.sp. differs 56.47% of observed S. ohridanus have been infected and average intensity of infestation is 2.84.