The aphid genus Stomaphis Walker, 1870 (Hemiptera: Aphididae: Lachninae) is Palaearctic origin group with 30 valid species. It is associated with variable woody host plants, having very long rostrum, which enables them to feed crevices in thick bark of trees. In this study, Stomaphis (stomaphis) pini pini is newly recorded in the Korean Peninsula on Pinus densiflora (Pinaceae). We described morphological features of alate viviparous females, apterous males and oviparous females, respectively. Furthermore, little known forms, sexual morphs of giant oviparous females and dwarfish apterous males are observed.

• Minho Lee(Insect Biosystematics Laboratory, Department of Agricultural Biotechnology, Seoul National University/Research Institute of Agriculture and Life Sciences, Seoul National University)
• Hongyul Seo(National Institute of Biological Resources, Environmental Research Complex)
• Hwalran Choi(Department of Biological Sciences, University of Memphis)
• Seunghwan Lee(Insect Biosystematics Laboratory, Department of Agricultural Biotechnology, Seoul National University/Research Institute of Agriculture and Life Sciences, Seoul National University)