Light and electron microscopic studies on Myxobolus egyptica sp. nov. (Myxozoa, Myxosporea), infecting the hornlip mullet Oedalechilus labiosus from the Red Sea

Abstract

A new myxosporean, Myxobolus egyptica sp. nov., was described from the gills of the hornlip mullet Oedalechilus labiosus, collected from the Red Sea at Al-Quseir city, Egypt. The prevalence of infection was 12/72 (16.66%). Myxobolus egyptica was identified on the basis of spore morphometry, histology and transmission electron microscopy. It was distinguished from all previously reported Myxobolus spp. by its shape, dimensions of the mature spore 10.0 ± 0.6 (9.5-10.5) μm in length, 8.5 ± 0.4 (8.0-9.0) μm in width and 8.7 ± 0.5 (8.4-9.2) μm in thickness, polar capsules, locality and host. The parasite formed intrafilamental cyst-like plasmodia. These plasmodia caused curling and atrophy of the gill lamellae. The ultrastructural analysis revealed a double-unit plasmodial membrane which was in direct contact with the host cells and had numerous vesicles. Some mitochondria were found below this membrane. The disporic pansporoblast was earliest recognizable stage of sporogenesis. Advanced developmental stages of spores and mature spores were reported. © 2011 Versita Warsaw and Springer-Verlag Wien.