Comparative Biology, Reproductive Compatibility, and Geographical Distribution of Amblyseius longispinosus and A. womersleyi (Acari: Phytoseiidae)

Abstract

Female and male Amblyseius longispinosus (Evans) and A. womersleyi (Schicha) were reared in an incubator at 28°C and a photoperiod of 13:11 (L:D) h. They were supplied with eggs of Tetranychus kanzawai Kishida for food. A. longispinosus matured in 5.02 and 5.0 d, and consumed 13.84 and 11.2 spider mites eggs, respectively. A. womersleyi matured in 4.92 and 4.67 d, and consumed 15.32 and 11.54 spider mite eggs, respectively. In the first 10 d after ec1osion, adult female A. longispinosus and A. womersleyi consumed an average of 26.43 and 32.07 spider mite eggs daily, and laid 2.92 and 3.07 eggs per day, respectively. A. womersleyi developed slightly faster than A. longispinosus and was more voracious. Larvae of both species were observed eating spider mite eggs. Adult female A. womersleyi incompletely consumed spider mite eggs when food was abundant. When mated with male A. longispinosus , all female A. womersleyi oviposited but with reduced fecundity. Only male offspring were produced and 47.8% of eggs were nonviable. However, only 1.5% of female A. longispinosus that mated with male A. womersleyi oviposited, but offspring of both sexes were produced. Hybrid F1 progeny inherited the maternal setal length of dorsal seta L8 in all reciprocal matings. These findings suggested that these two mites are distinct species. Their life cycles, food consumption, reproductive compatibility, and geographical distribution are discussed.