Donggu Jeon

Introduction The small crustacean class Copepoda is among the most successful metazoan groups, with more than 14 500 known valid species worldwide (Walter and Boxshall, 2024). They inhabit virtually every type of aquatic environment, ranging from the deep sea (Wolff, 1959; Suárez-Morales et al., 2026) to high-elevation mountain waters (Jersabek et al., 2001), and from hypersaline (Bayly and Boxshall, 2009; Anufriieva, 2015) to freshwater ecosystems (Reid, 1986; Huys and Boxshall, 1991).