Abstract: The control potential of the new natural enemy Andalusia spinidens to the invasive pest Spodoptera frugiperda was assessed by measuring the predation ability and functional responses of A. spinidens nymphs to S. frugiperda larvae and observing predatory behaviors. The results showed that the 4^th and 5^th instar nymphs of the predator exhibited strong predatory ability on the 3^rd―5^th instar larvae of S. frugiperda. Daily predation amount of the 5^thinstar nymphs on the 3^rd, 4^th, and 5^th instar larvae was 8.30, 6.33, and 3.80, and the highest predation of 5^th instar nymphs on 3rd instar larvae. For the 4^th instar nymphs on the 3^rd and 4^thinstar larvae, it was 4.67 and 2.93, respectively. In contrast, the 3^rd instar nymphs had weak predatory ability, only showing relatively strong predation on the 3rd instar larvae, with an average daily predation amount of 3.50. The predation of the nymphs on different instars S. frugiperda increased gradually with the increase of prey density and then stabilized, which fits well with the Holling Ⅱ functional response model. The searching ability, processing time and daily maximum predation of the 5^th instar nymphs on S. frugiperda were superior to those of the 3^rd instar nymphs, and the control efficiency of the 5^th instar nymphs was higher. The results serve as an important reference for using the predatory bugs in control of S. frugiperda.

Key words: Andalusia spinidens, Spodoptera frugiperda, predation ability