First record of the fungus Entomophthora infecting Philornis downsi, an invasive fly in the Galapagos Islands

The vampire y Philornis downsi is an obligate bird parasite that was introduced into the Galapagos Islands, probably accidentally from mainland Ecuador. Subsequently, the y dispersed to most islands in the archipelago, negatively impacting endemic land-bird populations. We report here the discovery of an entomopathogenic fungus of the genus Entomophthora, likely within the E. muscae complex, infecting P. downsi in the Galapagos Islands. The fungus was identi ed based on its morphology. This appears to be the rst record of a member of Entomophthora parasitizing the genus Philornis, and the rst record of a fungus in the E. muscae complex infecting any insect species in Galapagos. We hypothesise that this fungus is introduced rather than native in Galapagos and recommend further research on entomopathogenic fungi in South America.