Abstract
Museum beetle specimens are valuable resources for genetic analyses; however, obtaining DNA from aged specimens remains challenging due to degradation, desiccation, and contamination. In this study, we present a simple, low-cost protocol for extracting DNA from museum beetles, optimized using cetyltrimethylammonium bromide (CTAB). This method effectively addresses common issues such as DNA fragmentation and contamination, enabling the recovery of DNA suitable for downstream applications such as PCR and next-generation sequencing. It provides a reproducible, non-destructive approach to extracting genetic material from fragile beetle specimens, thereby facilitating molecular investigations in fields such as taxonomy and conservation biology. The protocol is summarized as follows:•A method for DNA extraction is optimized for museum beetle specimens preserved for over 45 years.•The protocol is non-destructive and compatible with PCR and next-generation sequencing.•Multiple extractions can be pooled to increase yields, particularly when DNA concentrations are low. This method broadens the possibilities for genetic analysis of historical specimens, offering new insights into long-term ecological and evolutionary processes.