The behavioral responses of foraging adults of Kallima inachus (Boisduval) (Lepidoptera: Nym-phalidae) to four colors and to six different fermented fruit juices were observed in order to determine the cues used by foraging adults. According to the results, adults did not show a behav-ioral response to red, yellow, purple, or white artificial flowers without food odors, but flowers with the fermented pear juice strongly attracted them, and they showed a behavioral response to fermented juices of the six fruits (pear, apple, banana, watermelon, orange, and persimmon) with no statistically significant preference. The fruit volatiles were collected using dynamic headspace adsorption, and the volatile components were analyzed by auto thermal-desorption gas chroma-tography-mass spectrometry to assess which volatiles existed in the fruits. Only alcohols, esters, and ketones were common in the volatiles of all six fermenting fruits. The five volatile compo-nents found in the six fruits, as well as two others found to be in other fermented foods by previous studies, were selected to test the behavioral and electroantennogram (EAG) responses of naive adults to estimate behavioral preference and antennal perception. In field behavioral tests, alcohols were the most attractive, followed by esters, while α-pinene, butanone, and acetic acid were much less attractive. Relative to other volatile combinations and ethanol alone, the mixture of ethyl acetate and ethanol attracted the most feeding adults. The number of adults attracted was significantly positively correlated with the concentration of both ethanol and ethyl acetate. The EAG responses of naive adults showed that the EAG responses to 3-methyl-1-butanol, isoamyl acetate, ethyl acetate, α-pinene, butanone, and acetic acid were all higher than those to ethanol (100%) at doses of either 5 µl/mL or 50 µl/mL. Sexual differences only existed in 3-methyl-1-butanol and acetic acid at particular concentrations. Sexual differences in response to chemical mixtures were not significant at 50 µl/mL. In addition, the EAG responses in the within-sex trials were not correlated to the dosage (0.01, 0.1, 1, 5, 10, and 100µl/mL) of either ethanol or ethyl acetate. The results showed that olfactory cues played a crucial role in the foraging of adult K. inachus , and that foraging adults can use a variety of chemical signals derived from food; howev-er, the feeding preference to volatiles was not necessary correlated with the EAG responses.

Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is a well-known aphid predator in its native Asian habitat. Currently, H. axyridis are predominantly released for aphid control in China; however, light traps and colored sticky cards also were widely used to control aphid pests, which results in population reduction of H. axyridis. This study used 15 monochromatic and whole-spectrum lights to investigate whether H. axyridis has a particular light intensity and spectral preference. Positive phototaxis was found in both H. axyridis adults and larvae to a broad specturm of light. The phototactic responses of adult H. axyridis showed significant similarity to that of larvae. Female H. axyridis had four sensitivity maxima at 414, 492, 504, and 568 nm, male H. axyridis had four maxima of sensitivity at 380, 492, 504, and 549 nm, and H. axyridis larvae also had four maxima of sensitivity at 414, 504, 549, and 568 nm. The phototactic responses of H. axyridis to various monochromatic lights did not significantly differ between sexes. The larval response to a broad spectrum of light was significantly less than that of adults. Furthermore, H. axyridis adults of both sexes showed an increased phototactic response at low intensities and a decreased response at high intensities for both blue light and green light. Moreover, the phototactic response of both female and male H. axyridis was strongest at 10 lux. The males of H. axyridis are more sensitive to light intensity than females; however, the H. axyridis light intensity experiments between sexes showed no significant differences. These behavioral differences could be exploited for the development of selected colored light traps used for insect pest management.

Danaus genutia, commonly known as the tiger butterfly, is a visually appealing species in the Danaidae family. As it is not currently classified as endangered, it is excluded from key protected species lists at national and local levels, limiting focus on its population and habitat status, which may result in it being overlooked in local butterfly conservation initiatives. Yunnan, characterized by high butterfly diversity, presents an ideal region for studying habitat suitability for D. genutia, which may support the conservation of regional biodiversity. This study employs the MaxEnt ecological niche model, predictions regarding suitable habitat distribution, and trends for D. genutia and identifying primary environmental factors influencing their distribution. The results indicate that the niche model that includes interspecies relationships provides a distribution prediction closely aligned with the observed range of D. genutia. Under current climatic conditions, highly suitable habitats for both D. genutia and its host plant, Cynanchun annularium, are located predominantly in the Yuanjiang River Valley. Optimal conditions occur at average annual temperatures of 19.80–22 °C for D. genutia and 22–24 °C for C. annularium. The distribution range of C. annularium is a vital biological factor limiting D. genutia’s habitat. By 2040, projections under four future climate scenarios indicate a potential increase in the total area of suitable habitats for D. genutia, with a general trend of northward expansion.

This study aims to determine the local host plant range for Yuanjiang River Valley Danaus genutia (Cramer, 1779) and evaluate the effects of different host plants on its growth, development, and reproductive success. This research assesses adult oviposition preferences and larval feeding tendencies on various host plants. An age-stage, two-sex life table was constructed to analyze the butterfly’s growth, development, reproductive success, survival rates, and other physiological aspects on different host plants. Population dynamics over the next 60 days were simulated to offer a comprehensive evaluation of the host plant suitability for D. genutia. The results indicated that D. genutia adults preferred laying eggs on Cynanchum corymbosum, followed by C. annularium, C. rostellatum, and Asclepias curassavica, with very few eggs laid on Calotropis gigantea and Dregea volubilis. Larval feeding preferences were observed in the order of C. annularium > C. corymbosum > C. rostellatum, with A. curassavica consumed only by first-instar larvae, while C. gigantea and D. volubilis were avoided. Under identical room temperature conditions, larvae feeding on C. annularium and C. corymbosum completed a full generation. Larvae feeding on C. annularium exhibited shorter developmental periods and higher early survival rates compared to those feeding on C. corymbosum, with no significant differences in adult longevity, sex ratio, or number of eggs per female. Female adults did not die immediately after laying eggs. No significant differences in the intrinsic rate of increase (r), finite rate of increase (λ), net reproduction rate (R₀), or doubling time (T_d) were found between populations feeding on the two host plants. However, the gross reproductive rate (GRR) and mean generation time (T) were significantly lower in the population feeding on C. corymbosum. These results confirm C. annularium and C. corymbosum as host plants for D. genutia larvae and provide a theoretical and scientific basis for the conservation of the Yuanjiang River Valley D. genutia population.