Nematophagous fungi: a new endoparasite intermediate between Myzocytium and Lagenidium

Abstract

Myzocytium intermedium is described as a new endoparasite of Rhabditis nematodes. It produces laterally biflagellate zoospores which track the host and encyst in the vicinity of the body orifices. Infection of mature nematodes is by means of germ tubes from encysted zoospores which penetrate through the body orifices.The thallus is filamentous, much-branched, and nodular in appearance. At maturity it divides to form numerous segments of irregular size and shape. In the vegetative phase the parasite resembles a Lagenidium. In the sexual stage, however, the young antheridium cannot be distinguished morphologically from either the oogonial or zoosporangial segments. No fertilization tube is produced and the antheridial protoplast migrates through a pore in the common wall to fertilize the oogonium. After fertilization, a thick-walled, smooth, spherical oospore is produced.