An investigation on the habitation of Callipogon relictus Semenov was carried out in Gwangneung forest, Korea and Ussurisky nature reserve, Russia. During the investigation period (2007–2018), a total of 25 emergence holes, 10 pupal chambers, 10 adults, and two larvae of C. relictus were identified in Gwangneung forest. In this presentation, we provide biological information on habitation of C. relictus in Gwangneung forest by comparison and combination of survey results in Ussurisky nature reserve, in 2015 and 2018. In addition, the distribution range of C. relictus is also reviewed in the Korean Peninsula with a new location.

The genus Phymatodes Mulsant (Coleoptera: Cerambycidae) distributes throughout the Holarctic region. Approximately 50 species have been recorded from the world, and four species have been recorded in Korea. In 2010 and 2011, we collected many grape twigs which were severely damaged by unknown larvae of longhorn beetles from Gyeonggi province. They were reared at indoor condition until their emergences in order to see which species inflicted damage on the grape vines. Two species of unknown longhorn beetles were collected. They were identified as Phymatodes jiangi Wang et Zheng and P. zemlinae Plavilstshikov et Anufriev that are new to Korea. The diagnosis and illustrations of P. jiangi and P. zemlinae are provided.

Larval stages of Callipogon relictus (Semenov) (Coleoptera: Cerambycidae), a gigantic longhorn beetle designated as a natural monument of Korea, has never been studied as it is hardly discovered in nature. The DNA barcoding gene, mt-COI, was used to identify a dead larva found in the Gwangneung forest of the Korea National Arboretum. Based on the result, we provide the morphology of the immature stage, with the illustrations of diagnostic characteristics.