Recent additional records of the little-known mydas fly, Nemomydas gruenbergi (Hermann, 1914) (Diptera, Mydidae) from Iriomote Island, southern Japan, with the first documentation of mating and oviposition

This dataset contains occurrence records and voucher specimen information of Nemomydas gruenbergi (Hermann, 1914) (Diptera, Mydidae) collected from northern Iriomote Island, Yaeyama Islands, Japan. The data were obtained during summer field surveys and include both direct observations and preserved specimens. These records represent newly confirmed occurrences of the species from northern Iriomote, extending its known distribution in Japan. Notably, this dataset also includes photographic documentation of a mating pair and oviposition behavior, providing valuable biological information for this rarely recorded fly in East Asia.