|Symphylan Biological Control|
|Biology of the Predaceous Mite, Pergamasus
quisquiliarum,¹ on the Garden Symphylan, Scutigerella immaculata,² in the
RALPH E. BERRY
Department of Entomology, Oregon State University, Corvallis 97331
© 1973 Entomological Society of America
Ann. Entomol. Soc. Am 66:1354 - 1356 (1973)
The parasitid mite, Permagasus quisquiliarum Canestrini, was observed preying on the garden symphylan, Scutigerella immaculata (Newport), in a field near Corvallis, OR. All stages, except larvae, were collected in April and successfully reared on symphylans in the laboratory. The life cycle of P. quisquiliarum from oviposition to adult was 16.9±5.1 days at 20±1.0°C in the laboratory. The average developmental period for eggs was 4.6±0.7 days, larvae 1.2±0.4 days, protonymphs 5.4±1.9 days, and deutonymphs 5.7±2.1 days. The average number of immature symphylans consumed during the protoand deutonymphal stages was 3.6±1.3 and 3.7±1.3, respectively. Larvae did not feed. Adult mites lived an average of 37.0±12.8 days, during which time an average of 4.8±2.1 symphylans was consumed (1:1 ratio). The number of symphylans consumed in 1:2 and 1:5 predator-prey ratios was 7.7±3.4 and 11.0±5.5, respectively. The average number of eggs deposited per female was 32.6, with an average of 14.2 symphylans consumed/female.