Molecular identity, phylogeny and life cycle of Chloromyxum schurovi Shul’man & Ieshko 2003

Abstract

A myxosporean of the genus Chloromyxum sp., which sporulates in the kidney tubules, was detected in Atlantic salmon, Salmo salar L., and brown trout, Salmo trutta L., from three sites in Scotland. A comparison with other reports of Chloromyxum spores in the kidney of European salmonids suggests that they all refer to the same species, Chloromyxum schurovi [Shul'man BS, Ieshko EP (2003). Parazitologia 37:246-247]. Apart from Chloromyxum majori [Yasutake WT, Wood EM (1957). J Parasitol 43:633-637] which has a different geographical and host range, as well as tissue localisation, this is the only representative of the genus in the kidney of salmonids described so far. This study provides a re-description of C. schurovi including its myxosporean and actinosporean stage, i.e. Neoactinomyxum eiseniellae [Ormieres R, Frezil JL (1969). Protistologica 5:137-144], which was identified by 18S rDNA sequence identity. Results of phylogenetic analysis of the 18S rDNA sequence of C. schurovi and all other Chloromyxum species with published sequences showed that C. schurovi clusters with representatives of other myxozoan genera which inhabit the urinary system, whereas the other Chloromyxum species form a more basic clade together with another gall bladder parasite.