Supplementary studies on Myxobolus tsangwuensis Chen, 1954 (Myxozoa: Myxosporea) infecting the gills of common carp Cyprinus carpio (L.): molecular and histological data

Abstract

Myxobolus tsangwuensis Chen, 1954 is a common parasite infecting the gills of common carp Cyprinus carpio (L.). It was described simply in the original description and its molecular data was absent, which makes the accurate diagnosis challenging. Here we supplemented its description based on the morphological, histological and molecular data. It was characterized by the presence of small round or ellipsoidal plasmodia in the gills of host and histology showed the plasmodia developed in the capillary network of the gill lamella. Mature spores of M. tsangwuensis were ellipsodal in frontal view and lemon shaped in lateral view, averaging 11.2 ± 0.7 (10.2-12.5) μm × 9.3 ± 0.3 (8.5-10.0) μm × 6.2 ± 0.4 (5.5-7.0) μm. Spores valves were symmetrical and smooth. Occasionally, a small intercapsular appendix was observed. Two polar capsules were pyriform with different sizes, measuring 5.0 ± 0.2 (4.4-5.3) μm × 3.1 ± 0.1 (2.9-3.5) μm and 3.9 ± 0.2 (3.4-4.3) μm × 2.5 ± 0.2 (2.0-2.8) μm, respectively. Polar filaments coiled five to seven turns in large polar capsule and three to four turns in the small polar capsule. Some spores were surrounded by the mucous envelope that was not recorded in the original description. Molecular analysis revealed that the present SSU rDNA sequences did not match any available sequences in GenBank and phylogenetic analysis showed M. tsangwuensis was sister to M. basilamellaris and M. musseliusae.

Description of Myxobolus balatonicus n. sp. (Myxozoa: Myxobolidae) from the common carp Cyprinus carpio L. in Lake Balaton

“…Correct data 44 including histology, pathology and molecular results 45 are available for six European species: (M. basilamel-46 laris Lom & Molnár, 1983, M. cyprini Doflein, 1898, 47 M. cyprinicola Reuss, 1908, M. dispar Thélohan, 48 1895, M. encephalicus Mulsow, 1911and M. intra-49 chondrealis Molnár, 2000 (see Lom & Molnár, 1983;50 Molnár & Kovács-Gayer, 1985;Dyková et al, 1986;51 Antychowicz & Reichert 1987;Dyková & Lom 1988;52 Molnár 200052 Molnár , 2002a52 Molnár , 2009Cirkovic et al, 2010) and 53 for three Asian species (M. artus Achmerov, 1960, M. 54 musseliusae Yakovchuk, 1979 andM. tsangwuensis 55 Chen &Ma, 1998) (see Ogawa et al, 1992;Liu et al, 56 2013;Huang et al, 2014). 57 In a long-term parasitological survey conducted on 58 fishes from Lake Balaton in Hungary, a new species of 59 the genus Myxobolus was found.…”