Cannibalism and intraguild predation in the Phytoseiid mites Typhlodromips swirskii, Euseius scutalis and typhlodromus athiasae (Acari: Phytoseiidae)

Abstract

The intraguild predation and cannibalism on eggs and immatures by the adult females of Euseius scutalis, Typhlo-dromus athiasae and Typhlodromips swirskii were examined under laboratory conditions. Adult females of all three species exhibited higher predation rates on larvae than on protonymphs. Typhlodromips swirskii had higher predation rates on heterospecific than on conspecific prey and all females failed to predate on eggs and protonymphs of its own. Also, T. swirskii females were able to sustain oviposition when preying upon eggs and immatures of T. athiasae and E. scutalis, whereas cannibalizing T. swirskii females did not lay eggs and all died in a short time (6.0–7.3 days), respectively. Typhlodromus athiasae failed to predate on eggs as well as immatures of T. swirskii and females suffered a higher mortality than vice versa. Euseius scutalis females ate 6.0 larvae or 5.2 protonymphs of T. athiasae and 0.7 eggs or 0.4 larvae of T. swirskii per female per day. Females of E. scutalis were hardly able to sustain oviposition irrespective of conor heterospecific prey, so reproduction was very low. The present study indicates that phytoseiid immatures are suitable prey for surviving and reproduction of polyphagous phytoseiids.