ELECTRON-MICROSCOPY OF 2 TRICHOMYCETOUS FUNGI ATTACHED TO THE HINDGUTLINING OF PILL-BUGS

Two species of trichomycetous fungi, Asellaria armadillidii (Asellaria les) and Parataeniella armadillidii (Eccrinales), were found attached to the hindgut lining of the pill bug, Armadillidium vulgare. In the f ormer fungus, the thallus was composed of a basal cell bearing an apic al whorl of many lateral branches. Electron micrographs in ultrathin s ections showed that an electron-opaque holdfast substance surrounded t he rhizoidal projections of the basal cell. The cross wall of the thal lus was the typical bifurcate type of septum, i.e., the wall flared at the central perforation which was occluded by an electron-opaque plug . This is the third report of this type of septum in the order Asellar iales. The bifurcated structure of the septal wall was found to remain at the distal portion of the mature arthrospore cell wall. In P. arma dillidii, both primary and secondary infestation sporangiospores were examined in ultrathin sections. A number of electron-transparent pits, 40-50 nm in diameter, were found in the basal portion of the cell wal l of secondary infestation sporangiospores which were still contained inside the sporangium.