Myxobolus zhaltsanovae n. sp., is described from the gills of gibel carp Carassius gibelio found during a survey of myxozoans from the watershed of Lake Baikal, Russia, based on morphological and molecular characterizations. Plasmodia of M. zhaltsanovae n. sp. develop extravascularly and measure 500-1000 μm long, 25-100 μm wide. The myxospore is circular to oval, measuring 13.23 ± 0.09 (11.3-14.8) µm (mean ± SD, range) in length, 10.19 ± 0.07 (9.1-11.4) µm in width, and 6.49 ± 0.12 (5.4-7.2) µm in thickness. Polar capsules are unequal and subspherical; measurements of polar capsules are: length 5.62 ± 0.06 (4.7-6.7), width 3.44 ± 0.04 (2.4-4.4) µm and length 3.42 ± 0.05 (2.5-4.1), width 1.94 ± 0.04 (1.3-3.3) µm. Phylogenetic analysis with the 18S rDNA gene shows M. zhaltsanovae n. sp. as a sister species of the subclade formed by M. musseliusae, M. tsangwuensis, and M. basilamellaris, which infect common carp Cyprinus carpio.
Keywords: 18S rDNA; Gibel carp; Histology; Morphology; Myxobolus; Myxozoa.