Mating and diapause in hibernating adults ofMenida scotti puton (Heteroptera: Pentatomidae)

InMenida scotti aduts which mate during hibernation, we examined the effect of photoperiod on diapause induction in terms of the developmental degree of reproductive organs and corpora allata. In a hibernating population, mating season and physiological changes related to dipause were investigated. When newly emerged adults were reared under long- or short-day conditions, reservoir of the ectodermal accessory gland and corpora allata in males developed, while the developments of ovary and corpora allata in females were suppressed under both conditions. This suggests that diapause of this species is induced only in females independently photoperiodic conditions during adult stage. In a hibernating population, mating was observed from early to late November and from late March to early May. Observations of the development of reproductive organs and corpora allata suggest that diapause is induced only in females in the former period, while both sexes are not in diapause in the latter period.     

Nutritional contribution to females of14C-labeled male secretions transferred during mating inMenida scotti (Heteroptera: Pentatomidae)

Menida scotti (Puton) males have been shown to transfer secretions from their bulbus ejaculatorius and reservoir of ectodermal accessory gland to females by mating during hibernation. In the present study, the major components of the secretions were found to be proteins and lipids. To specify the female organ incorporating the male secretions, a radiotracer experiment in which the male secretions were labeled by [¹⁴C]valine was conducted in nine tissues of females collected in the fall and spring of the hibernation period. Relatively high radioactivities were detected in the haemolymph and the residual carcass (head, legs, air-sacs, exoskeleton, etc.) in the fall females, and in CO₂ gas evolved and carcasses in the spring females. The radioactivities in the fat body were significantly higher in the fall mating females than in the spring mating females, and vice versa in the ovary. The radioactivities in six fractions (lipids, proteins, glycogen, sugars, free amino acids and the residues) were also assayed in the five organs of females that had a relatively high radioactivity. The highest radioactivity was detected in the protein fraction of the haemolymph in fall and spring females. There were significant differences in the radioactivities incorporated into the lipid fractions of the carcass between fall and spring females.     

Estimation for change point of discretely observed ergodic diffusion processes

We treat the change point problem in ergodic diffusion processes from discrete observations. Tonaki et al. (2021a) proposed adaptive tests for detecting changes in the diffusion and drift parameters in ergodic diffusion process models. When any change in the diffusion or drift parameter is detected by this or any other method, the next question to consider is where the change point is located. Therefore, we propose the method to estimate the change point of the parameter for two cases: the case where there is a change in the diffusion parameter, and the case where there is no change in the diffusion parameter but a change in the drift parameter. Furthermore, we present rates of convergence and distributional results of the change point estimators. Some examples and simulation results are also given.