518 Invasive Stink Bugs and Related Species (Pentatomoidea)
(McPherson 1982). As could be expected, this predaceous stink bug revealed a much weaker influence
of food on the PhPR of diapause induction. The fraction of diapausing individuals among those reared
and then maintained in the laboratory on an unfavorable diet (larvae of the house fly, Musca domestica
L.) increased only around the critical photoperiod (Goryshin et al. 1988b).
11.4 Winter Diapause Per Se
As noted above and evident from Table 11.2, the great majority of pentatomoids overwinter as adults.
Winter diapause at this stage has been studied mostly in females, where it manifests itself most clearly
in arrested ovarian development, suppressed oogenesis, the absence of oviposition, and presence of well-
developed fat bodies. Thus, reproductively active females of Nezara viridula have mature (= chorionated)
eggs or vitellogenic oocytes in their ovarioles, and weakly developed or loose fat bodies (Figure 11.11C,E).
ABCDE FMature eggs
Fat bodySpermathecaOvariolesVas deferensVas deferensEctodermal
sacEctodermal
sacOocytes
SpermathecaEctodermal
sacFIGURE 11.11 (See color insert.) State of gonadal development in diapause and nondiapause adults of the southern
green stink bug, Nezara viridula. Nonreproductive female (virgin, prereproductive or in diapause): no oocytes in germaria,
clear ovarioles, and empty spermatheca (A). Nonreproductive male (virgin, prereproductive or in diapause): clear vasa def-
erentia and collapsed ectodermal sac (B). Reproductive female (nondiapause): developing oocytes with yolk and expanded
spermatheca (C); chorionated eggs in ovarioles and loose fat body (E). Reproductive male (nondiapause): yellow vasa
deferentia and expanded ectodermal sac containing milky white secretion (D, F). For details on morphology and descrip-
tion of stages of gonadal development in N. viridula see Esquivel (2009). Note that in the original publication (Esquivel
2009) images (A) and (B) refer to the gonads without development in virgin adults. In diapause adults, the gonads remain
basically in the same state until diapause termination. (A, B, C, and F are from J. F. Esquivel, Annals of the Entomological
Society of America 102: 303–208, 2009, with permission; D and E are courtesy of Dr. Jesus F. Esquivel.)