During parasitological investigations of perch P.fluviatilis L., in spring 1988 from waters of Szczecin Firth, noticed a presence of Henneguya wolinensis n.sp.
(Myxosporea: Bivalvulida) cysts on fish Pillboxes skin.Milk-white, oval cysts measured from 0.5 to 1.0 mm occurred under scales, on epidermis of all fish scaled body surface.
Dimensions of spore: body length 22.3-27.2 μm, total length 61.1-69.
3 μm, breadth 7.4-8.7 μm, polar capsules length 11.1-15.
1 μm, polar filaments length Diarrhea 120-160 μm.The new described species compared with H.creplini and H.psorospermica from gills founding on perch together with H.
wolinensis n.sp.