Pathogenicity of entomopathogenic fungi to Ornithodoros erraticus and 1 Ornithodoros moubata ( Acari : Argasidae ) 2 3 4

24 25 The argasid ticks O. erraticus and O. moubata are of great medical and veterinary 26 importance because they are vectors of the African swine fever virus and several species of 27 human relapsing fever borreliae. Biocontrol of these ticks using entomopathogenic fungi has not 28 been previously reported. We examined the pathogenicity to different developmental stages of 29 these two argasids of six strains of the fungal species Beauveria bassiana (strains Bb1764 and 30 Bb2157), Lecanicillium lecanii (strains Ll586, Ll618 and Ll3047) and Tolypocladium 31 cylindrosporum (strain Tc3398). Three strains, Bb1764, Bb2157, and Tc3398, caused in 32 Spanish O. erraticus mean mortality rates between 34.4% and 62% in 14-28 days post33 inoculation. Additionally, Bb2157 also induced in African O. moubata mean mortality rates of 34 31.9%. The remaining strains caused lower mortality rates and were not considered effective. 35 This is the first study in which some strains of entomopathogenic fungi are found to be effective 36 against argasid ticks of the genus Ornithodoros, and its results might justify further efforts 37 towards the application of entomopathogenic fungal strains as anti-argasid biocontrol agents 38 39 40 41 42