Myxobolus taibaiensis sp. n. was found in the inner intestinal wall of common carp, Cyprinus carpio Linnaeus, during the investigation of fish parasite fauna in Lake Taibai, located in the middle reach of the Yangtze River, China. The whitish ellipsoidal plasmodia, up to 2.9 mm long and 1.7 mm wide, developed in the circular muscle layer of the intestinal wall and produced significant compression into adjacent tissues, but no significant inflammatory responses were observed against this infection. Mature spores are oval in frontal view and lemon-like in lateral and apical view, averaging 10.2-11.2 µm (10.8 ± 0.2 µm) in length, 9.1-9.9 µm (9.6 ± 0.2 µm) in width and 6.1-6.6 µm (6.3 ± 0.1 µm) in thickness. Polar capsules are pyriform, equal in size, slightly converging anteriorly, measuring 4.4-5.4 µm (5.0 ± 0.2 µm) in length by 3.2-3.6 µm (3.4 ± 0.1 µm) in width. Polar filaments coiled with four to five turns and arranged perpendicular to the polar capsule length, measuring up to 106 µm. Myxobolus taibaiensis sp. n. is morphologically similar to Myxobolus rotundatus Achmerov, 1956 which also infects the inner wall of the intestine of common carp. However, the small subunit ribosomal DNA sequence identity was only 94%, generally beyond the intraspecies variation in the genus. Phylogenetically, this new species is sister to M. rotundatus and then clusters with M. shantungensis Hu, 1965 to form an independent common carp-infecting cluster within the Henneguya-Myxobolus clade., Xinhua Liu, Congjie Hua, Qianqian Zhang, Yuanli Zhao, Dong Zhang, Jinyong Zhang., and Obsahuje bibliografii
During a regular veterinary inspection of fishes from Lake Balaton, Hungary, echinostomatid metacercariae (Digenea), with collar spines characteristic of species of the genera Petasiger Dietz, 1909 and Paryphostomum Dietz, 1909, were found in the lateral line scales of a roach Rutilus rutilus (Linnaeus), an apparently unique site. In a subsequent examination of 586 fishes from 20 different species, similar infections were found in 11 species. The infection was virtually restricted to the lateral line scales, other scales being infected only incidentally. These encysted metacercariae had 27 collar spines, including eight larger angle spines and 19 smaller dorsal spines arranged in two rows. Two types of metacercarial cyst were found. One type had a cyst diameter of 138-171 µm × 105-120 µm and three central dorsal spines that were larger than the remainder and tended to resemble the angle spines. The second type of metacercarial cyst had a diameter of 128-157 µm × 105-115 µm and all 19 dorsal spines of the metacercaria were of a similar size. ITS sequences of the second type of metacercaria exhibited a 100% similarity to sequences of two adult Petasiger phalacrocoracis (Yamaguti, 1939) specimens collected from the gut of Phalacrocorax carbo (Linnaeus) in Hungary and to P. phalacrocoracis deposited in the GenBank database. Sequences obtained from two metacercariae of the first type showed a 2.8-2.9 % difference from sequences of the second type of metacercaria and from those of adult specimens of P. phalacrocoracis from cormorants. Based on these results, the second type metacercaria is considered to be a larval stage of P. phalacrocoracis, but the identity of the first type is uncertain. The unusual location of these metacercariae in the lateral line scales is discussed in relation to their transmission., Kálmán Molnár, David I. Gibson, Gábor Cech, Melitta Papp, Petra Deák-Paulus, Lajos Juhász, Norbert Tóth, Csaba Székely., and Obsahuje bibliografii