The description of Myxobolus meijiangensis n. sp. (Myxozoa: Myxobolidae) and its pathogenicity to the gills of goldfish

• Published in: Parasitology international Vol. 97; p. 102795
• Main Authors: Zhang, Jinye, Wang, Yueru, Zhao, Yuanjun
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.12.2023
• Subjects: Histopathology; Morphology; Myxobolus meijiangensis n. sp; Phylogeny; SSU rDNA; SSU rDNA; Histopathology; Phylogeny; Myxobolus meijiangensis n. sp; Morphology
• ISSN: 1383-5769; 1873-0329
• DOI: 10.1016/j.parint.2023.102795

Myxobolus Bütschli, 1882 is the most speciose myxozoan genus, although some species have only been described according to the morphological characteristics of spores. In the present study, a new Myxobolus species infecting the gill lamellae of goldfish from Chongqing, China, was described using a comprehensive analysis of morphological, molecular, and histological data. Mature spores were flat-pear in valvular view with tapering anterior and rounded posterior ends, measuring 11.0 ± 0.4 (10.4–11.6) μm in length and 10.3 ± 0.3 (9.6–11.0) μm in width. Two equal-sized elongate pyriform polar capsules were 5.6 ± 0.6 (4.5–6.4) μm long and 3.5 ± 0.5 (2.4–4.1) μm wide. Polar tubules were coiled with 8 or 9 turns. The small-subunit ribosomal DNA gene sequence length of the present species was 1951 nt, and the highest similarity was 97.99% with M. pyramidis. Comparative analysis of the morphological and molecular data revealed that the present species was distinct from other known myxosporeans. Plasmodia were located at the interlamellar troughs nearing the top of the primary gills. Infection by the present species destroyed the original structure of gill lamellae and caused an inflammatory response, eventually leading to fish dyspnea. The morphological, molecular, and pathological data from the present study can be used for aquaculture since they provide guidance for easy detection and future control of this myxosporidiosis. [Display omitted] •The present species can cause inflammatory response in the gill of goldfish.•The present species is a potential pathogenic factor for goldfish.•All results can be used for the diagnosis of myxosporidiosis in aquaculture.