Thelohanellosis
Symptoms
Cause
It is caused by parasitism of Thelohanellus, called Myxosporea.
There is not much effect on fish. The cases are too small to know about it, although it was recognized as white spot disease at first eye, but in the case (white spot disease), they will leave from fish body in a short time as we understand.
Countermeasure
No good medication, but it also can be cure naturally.
Since this is possibly affected by earthworm (such as tubifex), It can be prevented infection from eliminating the host.