Ki-Jeong Hong

The genus Myllocerus includes numerous economically important species because both adults and larvae cause damage to agricultural, horticultural, and forest crops. To date, 11 species of Myllocerus have been recorded from Sri Lanka. However, taxonomic knowledge remains limited, and specimens in established Sri Lankan institutional collections are scarce, with most historical material housed in overseas institutions. This study presents an updated account of Myllocerus species in Sri Lanka, including diagnostic characters, habitus images, distributional data, and the first illustrated identification key. Myllocerus angulatipes , M. equinus , and M. zeylanicus are Sri Lankan endemics, while M. undecimpustulatus undatus is native to Sri Lanka and adventive in the USA. Compared with southern India, the known Sri Lankan diversity of Myllocerus is low. This highlights the need for further field study and taxonomic revision.

Anoplophora chinensis (Coleoptera: Cerambycidae) is an invasive, economically important, quarantined wood-boring pest whose long-life cycle complicates laboratory rearing and management. This study investigated the combined effects of artificial diet, chilling duration, and temperature on pupation cues. Adults collected from the wild were allowed to oviposit, and newly hatched larvae were reared on a prepared artificial diet. Larval weight was recorded biweekly to assess growth and mortality. At 12 weeks of age, larvae were subjected to cold treatments at 5 °C or 10 °C for 9, 12, 14, 16, or 19 weeks, then returned to warm rearing conditions to monitor pupation. Additional chilling cycles were applied when necessary. Pupation percents increased with chilling duration, reaching 55% after 16 weeks at 10 °C compared with 16.7% after 12 weeks and none after 9 weeks. Developmental durations were 34.43, 55.93, and 88.65 weeks for larvae experiencing one, two, and three chilling cycles, respectively. Adults body weight was consistently lower than that of field-collected individuals for both males and females. These findings confirm that chilling is essential for pupation cues and demonstrate that both duration and temperature strongly influence pupation success. Importantly, the combination of artificial diet with optimized chilling regimes enhances pupation rates, providing a practical foundation for mass-rearing protocols of A. chinensis to support future research and management programs.

Aphids (family Aphididae) are among the most species-rich groups of Sternorrhyncha in the order Hemiptera, and have a complex life cycle that can include several different phenotypes that are perfectly adapted to specific ecological niches. However, because aphids have a small body size, indistinct appearance, and cryptic adult behavior, their species level identification is often difficult and may be time-consuming. To overcome these limitations, DNA barcoding has been employed as an effective tool for species identification. In this study, we conducted a DNA barcoding test based on 566 specimens of Korean Aphididae, representing 125 morphospecies. Based on intraspecific genetic divergence, a threshold of 2% was estimated to efficiently differentiate the morphospecies. Only 87 morphospecies (69.6%) identified across four species delimitation methods (namely, automatic barcode gap discovery, assemble species by automatic partitioning, Poisson-tree-processes or PTP, and Bayesian implementation of the PTP) were consistent with the morphological identifications of the species. This indicates the presence of many cases of cryptic diversity among the other morphospecies, except the abovementioned 87 species. Careful morphological examination of morphospecies exceeding 2.0% intraspecific variability revealed cryptic diversity in three species (Eriosoma yangi, Tuberculatus kuricola, and Greenidea kuwanai). Two morphospecies, Sitobion avenae and Aphis craccivora, also exhibited high intraspecific divergence and comprised a single molecular operational taxonomic unit. Overall, our findings indicate that DNA barcoding can be a powerful tool for identifying species belonging to the family Aphididae, while also revealing cases of cryptic diversity.

The checklist comprises 264 species in 122 genera and 10 subfamilies of the family Curculionidae (excluding the subfamilies Scolytinae and Platypodinae) recorded from Sri Lanka. Among these, 175 species are endemic or potentially endemic to Sri Lanka. The checklist includes synonyms, type localities, and species distributions across Sri Lanka, categorized by biogeographic zones and localities where available. The Central Province supports the maximum diversity of Curculionidae followed by the Nuwara Eliya District (94 species), Kandy District (40 species), and Matale District (19 species). The Anuradhapura District in the North Central Province exhibits the third-highest species diversity (23 species) of Curculionidae. Sitophilus linearis (Herbst) (Dryophthorinae: Rhynchophorini) and Rhinoncus paganus Gyllenhal (Conoderinae: Ceutorhynchitae: Phytobiini) are recorded for the first time from Sri Lanka.

Tropical and subtropical crops are being increasingly cultivated in South Korea, leading to an increase in damage by exotic insect pests. Consequently, ethyl formate (EF) is currently being considered for quarantine and pre-shipment fumigation. In this study, we evaluated the effectiveness of EF fumigation for controlling Aphis spiraecola Patch and Aphis gossypii Glover, two representative quarantine pests on passion fruit (“Pink Bourbon”) during greenhouse cultivation and post-harvest storage. The efficacy of EF against both aphids in terms of the lethal concentration causing 50% mortality (LCt_50%) and LCt_99% was 1.36–2.61 g h/m³ and 3.73–7.55 g h/m³ under greenhouse conditions (23 °C), and 1.37–2.02 g h/m³ and 3.80–14.59 g h/m³ post-harvest (5 °C), respectively. EF at 4 g/m³ for 4 h resulted in 100% mortality of A. spiraecola, which was more resistant to EF, without causing phytotoxic damage to the trees in a 340 m³ greenhouse. Post-harvest fruit fumigation at 10 g/m³ for 4 h in a mid-size (0.8 m³) fumigation chamber resulted in complete disinfection. Moreover, the EF level decreased below the EF threshold within 10 min after natural ventilation in the greenhouse. Therefore, our results suggest EF fumigation as an effective method for controlling A. spiraecola and A. gossypii.

This study investigated the effect of chilling temperature and duration on diapause termination in Eurytoma maslovskii, a major apricot pest in Korea and China. The experimental insects were sampled in mid-autumn. Overwintering larvae were subjected to a temperature range at −16, −4, 2, 9, 13 °C for 12 wk (a temperature of 19 °C was used for nonchilled control), and then exposed to cold temperature (2 °C) for different durations (from 1 to 16, 19, and 22 wk) at different times (20 September and 30 November) to determine adult emergence, prolonged larval diapause, and development rate postchilling. The results demonstrated a strong association between chilling temperature and duration with the emergence of E. maslovskii. It was observed that diapause may be terminated after at least 6 wk in the cold. However, the rate only reached a higher significance after 10 wk or longer duration of chilling. The optimal chilling temperature ranged from 2 to 9 °C. Late autumn chilling (mid-September) did not differ from winter chilling (late November). The postdiapause development rate of E. maslovskii was determined to be affected by the chilling duration and could be described by a 3-parameter probability density Weibull function. These results suggest that winter conditions play a crucial role in the phenology of E. maslovskii in spring.