A NEW HARPOSPORIUM WITH TRIANGULAR CONIDIA ATTACKING BDELLOID ROTIFERS

Harposporium trigonosporum is described as new. After ingestion by rotifers, the triangular conidia lodge any place between the mouth and the anus but most frequently in the lower gut. A filiform germination hypha develops from each corner of the conidium and penetrates through the gut wall into the body cavity of the host. The host frequently responds to this invasion by laying down deposits around the advancing germ tube that sometimes causes the germinating conidium to abort. More frequently a germination hypha breaks through the host deposits at one or more of the three points of attack and proliferates inside the body, resulting in the death of the rotifer.