Supplementary datasets for <b>Resolving the identities of salmonid </b><b><i>Sphaerospora </i></b><b>and </b><b><i>Myxidium</i></b><b> infections using combined morphological and molecular evidence</b>

Additional sequencing of salmonid kidney-derived myxidiids revealed two morphologically and phylogenetically distinct lineages within the <i>Myxidium</i> sensu stricto clade. A shorter, stouter morphotype was consistent with <i>M. minteri</i>-like infections, whereas a more elongate morphotype with pointed spore ends corresponded to <i>M. salvelini</i>-like infections. The latter lineage included both the previously published sequence assigned to <i>S. oncorhynchi</i> and the CKX parasite associated with proliferative renal myxosporidiosis in coho salmon, supporting the interpretation of CKX as a likely proliferative stage of an <i>M. salvelini</i>-like parasite.

Gallbladder infections from coho salmon were identified as <i>Myxidium truttae</i>. These results demonstrate that mixed infections can cause erroneous sequence assignments and that phylogenetic context is important to consider, particularly if in conflict with well-supported clades.</p><p><br></p>