Description of four new Gunungiella species from central Vietnam (Trichoptera, Philopotamidae)

Four previously unknown species of Gunungiella Ulmer, 1913 are herein described from the Bach Ma National Park in the Phu Loc commune of Hue City, located in central Vietnam: G. phulocensis sp. nov ., G. bacmaensis sp. nov ., G. vietnamensis sp. nov ., and G. hueensis sp. nov . These species are considered rare and are only encountered as singletons. The specimens were collected in March and April 2023 using Malaise traps and light traps, which were strategically positioned along stream banks. The habitats are permanent, medium-sized, clear-water streams with slow to fast-flowing currents and stony bottoms, surrounded by dense forests on steep slopes. A key for the identification of male individuals of the thirteen known Gunungiella species in Vietnam is provided.