A first rearing record of the small-headed fly Ogcodes fumatus (Erichson, 1846) from the running crab spider Philodromus cespitum (Walckenaer, 1802) is reported. Aberrant web spinning activity of the host spider is documented. Molecular work comprises DNA barcoding (COI) for the host and parasitoid as well as PCR assays (16S rRNA, wsp) detecting the presence of at least two strains of Wolbachia bacteria in O. fumatus. A Neighbour-joining search of the 16S rRNA clusters these strains within supergroup A of Wolbachia.