Zoophthora

Zoophthora is a genus of fungi in the family Entomophthoraceae, order Entomophthorales, within the phylum Entomophthoromycota. Members are obligate pathogens of arthropods, predominantly insects, and are distributed worldwide in soils, leaf litter, and on plant surfaces or cadavers. They play a role in regulating insect populations and are often observed in localized disease outbreaks in natural and agricultural settings.

Infection by Zoophthora begins when asexual conidia produced on conidiophores contact susceptible insect hosts. The conidia adhere, germinate, and penetrate the cuticle, typically via enzymatic degradation and mechanical pressure. The fungus proliferates within the host, eventually causing death, after which it produces new conidia that exit the cadaver to disseminate and infect additional hosts. In some cases, infected insects display behavior such as climbing to elevated positions (summit disease) to enhance spore dispersal.

Zoophthora species form resting spores that enable survival under unfavorable environmental conditions, and sexual reproduction occurs through zygosporangia formed by mating of compatible strains. The genus is part of a broader group of entomopathogenic fungi that includes several other genera, many studied for their potential as biological control agents. However, practical use is often limited by host specificity, production challenges, and environmental factors affecting efficacy. Taxonomic placement has evolved with molecular data, but Zoophthora remains recognized as a component of Entomophthoromycota, comprising species that specifically target insect hosts.