Loma salmonae is a species of microsporidian parasite, infecting Pacific salmon (Oncorhynchus spp.).

L. salmonae is the causative agent of microsporidial gill disease of salmon.

It is an intracellular parasite which induces respiratory distress, secondary infection, and increased mortality rates.

Loma salmonae enters the Oncorhynchus host's gut via an infective spores.

In the heart, the host's immune system phagocytizes the parasite.