Black bear (Echeveria spp.) and Adromischus maculatus are ornamental succulents that change color in response to light and temperature. Colors of leaves play an important role in their ornamental value and market demand. However, there is a lack of quantitative research on flavonoids contained in succulent leaves. In this study, a colorimeter and ultra-performance liquid chromatography (UPLC) were used to analyze color changes of leaf surfaces and components of bioactive substances to understand the relationship between color change and internal bioactive substances of black bear and A. maculatus. The colorimeter analysis showed that red, green, and blue colors of black bear increased by 42.31%, 49.32%, and 21.58%, respectively, compared to their initial values, resulting in a clear change in leaf color from reddish-black to green. On the other hand, in A. maculatus, the red color decreased by 0.15% and the green color decreased by 10.44%, resulting in a more pronounced red spotted pattern and an increased area. UPLC analysis detected quercitrin in Black Bear leaf extracts and quercetin-3-O-sambubioside in A. maculatus. These substances are considered to play a key role in the concentration of anthocyanins and color changes in response to environmental changes such as light and temperature. Results of this study could be used as basic data to understand the correlation between leaf color change and bioactive substances in succulents in response to light and temperature.

Sexual dimorphism of the mouthpart, antenna and mandible of the Cyllorhynchites ursulus in South Korea was studied with linear measurements. The mouthpart and antenna measurements were conducted with a stereoscopic microscope using 122 specimens (72 males and 50 females). Microscopic observation of the mandible were conducted with a Field Emission Scanning Electron Microscope (FE-SEM) using 103 specimens (73 males and 30 females). Results showed that the size difference between males and females was significant in the size of the mouthpart and antenna. On the other hand, we could not detect sexual size dimorphism in the microstructure of the mandible. The bivariate plots made by the result of Principal Component Analysis (PCA) and Discriminant Analysis (DA) showed a size dimorphism in the size of the mouthpart and the antenna between males and females. Based on our study, sexual dimorphism in the mouthpart and antenna exists in C. ursulus from the South Korean population, and this difference seems to be related to the behavioral differences between males and females.

도토리에 구멍을 뚫고 가지를 자르는 도토리거위벌레(Cyllorhynchites ursulus, n=130)의 큰턱(mandible)의 외부형태 와 가지를 자르는 기작을 생체모방에 이용하기 위하여 분석을 하였다. 또한 큰턱의 외부형태와 자르는 기작비교를 위하여 비슷한 습성을 가진 밤바구미(Curculio sikkimensis, n=30), 왕거위벌레(Paracycnotrachelus longiceps, n=15)의 큰턱 외부형태를 분석하였다. 외부형태 분석을 위하여 각 종의 큰턱을 주사형전자현미경(SEM)으로 촬영, 도토리거위 벌레의 자르기 행동과 뚫기 행동은 영상 촬영으로 분석하였다. 도토리거위벌레는 큰턱을 좌우로 움직이며 3개의 톱니형태의 이(teeth)가 있으며, 밤바구미의 큰턱은 상하로 움직이며 2개의 톱니형태의 이가, 왕거위벌레는 좌우로 맞물리면서 씹는 움직임이며 톱니형태의 3개의 톱니형태의 이를 가지고 있다. 도토리거위벌레는 큰턱의 내·외전건 (adductor · abductor tendon)을 움직여 구멍을 뚫고 가지를 자르는 것으로 분석이 되었으며 외전건이 내전건보다 굵어 더 큰 힘이 바깥쪽으로 작용하는 것으로 분석되었다.