Germination and morphology of zygospores in two Cochlonema and one Acaulopage species

Abstract

Germination of zygospores in three amoeba-destroying zoopagalean fungi was observed for the first time in Cochlonema cerasphorum and C. megalosomum in the Cochlonemataceae and Acaulopage lophospora in the Zoopagaceae. Zygospores were maintained on agar plates in their resting state 2–6 mo before germination. Active protoplasmic movement of minute granules, 0.3–0.5 μm diam, was observed within 24 h of germination and was clearly visible due to the disappearance of the thick cell wall of the zygospore proper. In the two species of Cochlonema the germ tube formed an aerial conidiogenous hypha with a few branches, each of which modified to form a chain of conidia. In A. lophospora the germ tube became a vegetative hypha that captured amoebae by adhesion. Zygospores of C. cerasphorum were found for the first time in the present study.

• Acaulopage lophospora
• Cochlonema cerasphorum
• Cochlonema megalosomum
• Cochlonemataceae
• Zoopagaceae