Ecological study on helminths of three species of Gobiidae from the Danube River, Bulgaria.

A total of 72 specimens of (Kessler, 1857), (Pallas, 1814), and (Pallas, 1814) from four sampling sites along the Bulgarian section of the Danube River (Kudelin, Novo selo, Koshava, and Kutovo), Northwestern Bulgaria were submitted to ecologohelminthological investigation. During the examination 6 species of helminths have been identified from 3 classes: Trematoda ( (Iwanitzky, 1928) Dollfus, 1960), Acanthocephala ( (Müller, 1780) Lühe, 1911; (Müller, 1776) Lühe, 1911; (Zoega in Müller, 1776) Porta, 1908) and Nematoda ( sp., Jägerskiöld, 1909).

New Data on Endohelminth Communities of Barbel from the Bulgarian Part of the River Danube.

Species diversity and composition of the parasite communities of barbel () at the infracommunity and component community levels were studied in the Lower Danube River, Bulgaria. During the two-year investigations, five parasite species have been found in 92 host fish: (Cestoda), and (Acanthocephala) and larval stages of sp. and (Nematoda).

Morphological polymorphism in tapeworms: redescription of Caryophyllaeus laticeps (Pallas, 1781) (Cestoda: Caryophyllidea) and characterisation of its morphotypes from different fish hosts.

Recent morphological and molecular data have shown that one of the most common parasites of freshwater fish in the Palaearctic Region, the cestode Caryophyllaeus laticeps (Pallas, 1781) (Eucestoda: Caryophyllidea), is highly polymorphic. Five distinct morphotypes of C. laticeps, largely corresponding to different fish hosts and representing separate, yet closely related genetic lineages, have been recognised and they are characterised in the present paper.

Helminth communities of the rudd Scardinius erythrophthalmus (Cypriniformes, Cyprinidae) from Srebarna Biosphere Reserve, Bulgaria.

A total of 180 individuals of Scardinius erythrophthalmus from Srebarna Lake, north-east Bulgaria, were examined for helminth parasites during spring, summer and autumn of 2005-2006 (30 specimens per season). Helminth parasites were recorded in 166 individuals (92.2%).