Distance of conidial discharge of Entomophthora muscae and Entomophthora schizophorae (Zygomycotina: Entomophthorales)

The distance traveled by conidia of the E. muscae species complex from cadavers of Musca domestica was measured. Laboratory strains of E. muscae and E. schizophorae, as well as a field-collected strain of E. muscae, were compared in darkness under still air conditions at 21°C. Most conidia were discharged <3.75 cm from the cadaver, with a range of 0 to 8.75 cm. When a fly cadaver was affixed to a vertical surface (normal death orientation), conidia discharged from the dorsum of the abdomen traveled further than conidia discharged from the lateral regions. Cadavers suspended in midair discharged similar numbers of laboratory strain E. muscae conidia similar distances from the venter, dorsum, or lateral abdomen. This suggested a boundary layer effect caused the reduced lateral discharge distance in earlier trials. Average discharge distance was positively related to cadaver size. A laboratory strain of E. muscae discharged conidia further than did a field strain of E. muscae and a laboratory strain of E. schizophorae.