Biology of the Pine Snittlebug. Aphrophora flavipes (Homoptera: Cercopidae) in the Nymphal Stage

Abstract

Biology and ecology of the pine spittlebug Aphrophora flavipes in the nymphal stage was studied in six year-old Pinus densiflora (12 trees) and P. thunbergii (13 trees) in the University Forest Experiment Station at Tanashi (Tanashi City, Tokyo) in 1984. The nymphs hatched from the end of April through the end of May and developed to the adult stage passing through five instars which lasted about 60 days. The nymphs produced masses of froth (“spittle”) exclusively on the current year and previous year growths and the average number of nymphs contained in a mass was significantly greater than unity throughout the season. The nymphs dispersed among the branches, resulting in changes in their vertical distribution in June. Density of the nymphs per branch was evaluated by stratifying the branches in relation to their height (and age as well): the weighted average density was 10.5 and 14.0 per branch, or 290 and 328 per tree, for P. densiflora and P. thunbergii, respectively. Daily survival rate was estimated to be 0. 990 and 0. 970 on P. densiflora and P. thunbergii, respectively. No predation of the nymphs by any arthropod predators coexisting on the pine trees could be observed. © 1986, JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY. All rights reserved.