A microsporidian pathogen of the predatory beetle Rhizophagus grandis (Coleoptera: Rhizophagidae)

Abstract

A newMicrosporidium sp. infects Rhizophagus grandis Gyllenhall, a beetle which preys on the bark beetle Dendroctonus micans Kugellan in Turkey. Mature spores are single, uninucleate, oval in shape (3.75 ± 0.27 μm in length by 2.47 ± 0.13 μm in width), with a subapically fixed polar filament. The polar filament is anisofilar, coiled in 7-8 normal and 3-1 reduced coils. Other characteristic features of the microsporidium are the four/five nuclear divisions to form 16/32 (commonly 16) spores, subpersistent sporophorous vesicles (pansporoblasts) remaining till formation of the endospore, and the vesicles dissolved with free mature spores. The polaroplast is divided into three zones: an amorphous zone, dense layers, and a lamellartubular area extending to the central part of the spore. © Institute of Parasitology, Biology Centre ASCR.