Zschokkella helmii n. sp. ( Myxozoa : Myxosporea ), a new parasite of marbled spinefoot Siganus rivulatus (Forsskal 1775), Red Sea, Egypt: light and transmission electron microscopy.

Abstract   Zschokkella helmii n. sp., a new parasite of Siganus rivulatus from the Red Sea, Egypt, was described using light and transmission electron microscopy. However, the infection was severe; single “histozoic” plasmodium was encountered in the gallbladder wall. Spores are ellipsoid with 9–11 valvar striations. Spore mean length is 10.8 μm (10.0–11.0), while the spore mean width is 7.5 μm (7.0–8.0). Polar capsules are nearly round with a diameter of 2.2 μm (2.0–3.0) and have five filaments. Ultrastructure of the plasmodial wall and sporogenesis of the present species followed the usual pattern valid for most studied myxosporean species. [ABSTRACT FROM AUTHOR]