Hermetia illucens L. (Diptera: Stratiomyidae), a well-known decomposer of organic wastes, is widely applied to treat food, livestock, and poultry wastes to reduce environmental pollution. It is also used to produce high-protein feed, organic fertilizers, and biomedicine as well as biodiesel. The development of the endo-reproductive system in insects plays a crucial role in their reproduction, which is key in economic insect culture. In this study, we investigate the developmental process of the endo-reproductive system and the effect of mating status on the development of the female reproductive system in adult H. illucens. The results show that the morphological characteristics of the internal reproductive system of adult H. illucens differed with age and mating status. Males exhibited a higher testicular dimension at 2–5 days old, with testicular length and width reaching their maximum at 3 days old, displaying significant differences across ages (p < 0.05). The developmental period of the ovaries varied with time and was classified into five distinct stages. The morphological characteristics of the endo-reproductive system of adult females at different mating status showed differences. The spermatheca of the unmated female was translucent, while that of the mated female exhibited cloudiness and became lighter in color with age. The length and width of the spermatheca of the mated female were larger than that of unmated females (p < 0.05). However, the length and width of the spermathecae of the mated and unmated females reached their maximum at 5 days old. Mating status affected the development of eggs; mated females oviposited matured eggs at 5 days old, while unmated females oviposited matured eggs at 9 days old. The results suggest that mating status can promote the development of eggs in H. illucens. Additionally, the maturity level or mating status can be determined based on the morphology of the endo-reproductive system and its contents.

Atherigona orientalis (Diptera: Muscidae) may be a neglected agricultural pest worldwide since the public generally regards it as a saprophytic and sanitary insect. In fact, A. orientalis can infest over 50 varieties of fruits and vegetables in 26 families listed as quarantine pests in several countries. Regrettably, there are few reports of this pest despite its prevalence in the pantropical regions of many countries. In this study, we reported the distributions, morphological, and biological characteristics, including the host ranges, developmental durations, color selections, and population dynamics changes of A. orientalis in Hunan Province. Currently, A. orientalis has been found in each prefectural and municipal city of Hunan Province, China. Additionally, 15 out of 20 host plants we collected were infested. The developmental durations of the egg, larva, and pupa of A. orientalis ranged from 2 to 3, 5 to 7, and 6 to 8 days, respectively. The results of color selections showed that A. orientalis adults tend to prefer green and yellow colors. Moreover, the population dynamics of A. orientalis in Changsha City showed that July and August were the population peaks throughout the year. Our research supplements valuable data of A. orientalis for pest management and subsequent studies.

The red swamp crayfish Procambarus clarkii is one of the global invasive species and has caused huge damage to aquaculture, biodiversity and ecology in the world. Antennal-expressed receptors are important for P. clarkii to detect olfactory cues for mate attraction, et al.. However, few olfactory and chemosensory-related genes were reported in P. clarkii until now. In the present study, we used RNA sequencing to investigate the olfactory and chemosensory-related genes of the antenna of P. clarkii during the non-mating and mating period. A total of 59218 unigenes with an average length of 1056.41 bp, and 4889 differentially expressed unigenes (DEGs) with 2128 up-regulated and 2761 down-regulated unigenes were obtained. Of which, 13 up-regulated and 9 down-regulated DEGs were identified to associated with olfaction and chemical reception, including 4 IRs or iGluRs, 8 G-protein coupled receptor, 5 transient receptor potential channels (TRP channels), 1 sodium-calcium exchanger, 1 olfactory receptor, 1 isomerase and 2 chemosensory proteins (CSPs). CSPs were preliminarily classified into pheromone receptors in male red swamp crayfish. The results of quantitative real-time reverse transcription PCR (RT-qPCR) showed that the expression trends of 8 selected unigenes were consistent, and this result also validated the RNA-Seq data. Our results provide more comprehensive data of olfactory and chemical communication mechanism after crayfish entering the mating period.

The courtship behavior of moths is closely related to the biosynthesis and release of sex pheromones. To understand the mechanisms of the reproductive behavior of the ghost moth Endoclita davidi, a host insect of Cordyceps xuefeng (Ophiocordyceps xuefengensis), this study examined the courtship behavior and the ultrastructure of the sex pheromone gland of E. davidi. Infrared photography was used to analyze the courtship behavior, while SEM, paraffin tissue sectioning, and TEM were employed to examine the sex pheromone glands on the hind tibia. The courtship behavior of E. davidi occurs during the scotophase, during which males vibrate their wings and unfold the hairpencils located on the hind tibiae to lure the female moths. The hairpencil’s surface features regular longitudinal ridges interspersed with multiple circular pits. Multiple small holes were evident on the slightly enlarged areas close to the ends of the hairpencils. These small holes, formed at the base of the circular pits, connect to the internal glandular duct within the hairpencil, which links to the tibia glandular canal. The epidermal layer of the hind tibiae contains numerous glandular canals and dense microvilli. The glandular cells, specialized from dermal cells, contain numerous mitochondria, rough endoplasmic reticulum, clear vesicles of varying sizes, and round lipid droplets. The sex pheromone glands of male E. davidi release pheromones through the hairpencils in the hind tibia. The courtship behavior and ultrastructure of the sex pheromone gland of the male E. davidi provide a basis for further understanding pheromone release and communication mechanisms.